MEDICAL SCHOOL 
 
 COLLEGE OF PHARMACY 
 
o f Pharmacy 
 
PROGEESSIVE PROBLEMS 
 
 GENERAL CHEMISTRY 
 
 BY 
 CHARLES BASKERVILLE, PH.D. 
 
 PROFESSOR OF CHEMISTRY 
 AND 
 
 W. L. ESTABROOKE, Pn.D. 
 
 INSTRUCTOR IN CHEMISTRY 
 
 COLLEGE OF THE CITY OF NEW YORK 
 
 College of Pharmacy 
 
 REVISED 
 
 D. C. HEATH & CO., PUBLISHERS 
 BOSTON NEW YORK CHICAGO 
 
COPYRIGHT, 1910, 
 BY D. C. HEATH & Co. 
 
 2B O 
 
PREFACE 
 
 THE application of the principles of a science is the 
 surest test of their understanding. The more thor- 
 oughly students are drilled with Problems, the surer 
 is the teacher that his work has been worth while. 
 To save time, and such is recognized as a distinct factor 
 in modern pedagogy, problems from many sources have 
 been brought together in this book. They have been 
 taken from college examinations (American, European, 
 and Australian), regents' examinations, College En- 
 trance Examination Board papers, text books of all kinds, 
 and such books dealing especially with chemical prob- 
 lems, arithmetic, or calculations as those of Thorpe, Tate, 
 Foye, Waddell, Taylor, Miller, Hale, Dennis, Carpenter, 
 Lupton, Talbot, etc. Many original problems have also 
 been incorporated. If the student has successfully 
 solved two hundred selected problems from this list, 
 it may be safely said that he has acquired a fairly sound 
 comprehension of the basic principles of chemistry. 
 
 No attempt is made to incorporate these principles, 
 for they are gone into in the presentation of the subject, 
 whatever text may be used or whatever method be pur- 
 sued. A type series, however, is given in Chapter XIV. 
 The number of problems is sufficiently great to admit 
 of the use of the book a number of years before solutions 
 of the problems may be handed down from one class 
 to another. 
 
 42*17 
 
iv PREFACE 
 
 It will be observed that the student must seek much 
 necessary information from his text or such handy 
 reference books as Biedermann's Ohemiker Kalendar 
 or Van Nostrand's Chemical Annual by Olsen. Our 
 experience has shown good results accruing by hav- 
 ing such reference books conveniently placed in each 
 laboratory. 
 
 If the previous training of the student has been 
 sound, consideration of Chapter I may be omitted ; but 
 it may be well to prove this by testing. It is a remark- 
 able fact that college students, although they may 
 know the metric system thoroughly, cannot think in 
 its terms and are " up in the air" as soon as a question 
 is propounded in meters, cubic centimeters, etc. 
 
 No attempt has been made to render the nomenclature 
 uniform. The student thus has an opportunity to learn 
 the various terms in good usage among English-speak- 
 ing peoples, and he furthermore becomes more or less 
 familiar with the everyday parlance among so-called 
 practical men. 
 
 Our thanks are due Mrs. W. L. Estabrooke and 
 Mr. E. A. Stevens, who assisted in collating. Mr. W. A. 
 Hamor kindly followed the proofsheets. 
 
 REVISED EDITION 
 
 Helpful suggestions on the part of many teachers 
 have prompted us to incorporate much useful data in 
 an appendix. All detected errors have been corrected 
 and a booklet containing the answers to the problems 
 has been prepared. This may be obtained by teachers 
 on request to the publishers. 
 
 CHARLES BASKERVILLE. 
 
 JUNE, 1911. W. L. ESTABROOKE. 
 
CONTENTS 
 
 CHAPTER PAGE 
 
 I. MEASUREMENT 1 
 
 Metric System 
 
 Linear Measure . . . . . . 1 
 
 Surface Measure ...... 3 
 
 Volume ........ 4 
 
 Weight 6 
 
 Thermometry 8 
 
 Specific Gravity of Solids and Liquids . . .11 
 
 II. MOLECULAR WEIGHTS FROM ATOMIC WEIGHTS . 16 
 
 III. PERCENTAGE COMPOSITION 20 
 
 IV. CHANGES IN VOLUME 26 
 
 i. Due to change in pressure .... 26 
 
 ii. Due to change in temperature .... 29 
 
 iii. Due to change in both pressure and temperature 34 
 V. VOLUMES OF GASES FROM WEIGHTS SPECIFIC 
 
 GRAVITY AND VAPOR DENSITY .... 48 
 
 VI. WEIGHTS FROM EQUATIONS 56 
 
 VII. VOLUMES FROM EQUATIONS . . . . .80 
 VIII. PROBLEMS IN COMBINING VOLUMES OF GASES 
 
 (Gay-Lussac's Law) 107 
 
 IX. CALCULATION OF FORMULAS ..... 118 
 X. ATOMIC AND MOLECULAR WEIGHT CALCULATIONS 129 
 XI. ELECTRO-CHEMICAL PROBLEMS ..... 140 
 XII. ANALYTICAL CALCULATIONS STRENGTH OF SOLU- 
 TIONS 143 
 
 XIII. REVIEW SYSTEMATIC AND MISCELLANEOUS . . 164 
 
 XIV. PROBLEMS BASED ON EQUATIONS .... 225 
 
vi CONTENTS 
 
 APPBNDIX PAGE 
 
 I. INTERNATIONAL ATOMIC WEIGHTS .... 245 
 
 II. PERIODIC ARRANGEMENT OF THE ELEMENTS . . 246 
 
 III. THE METRIC SYSTEM CONVERSION TABLES AND 
 
 MENSURATION RULES 247 
 
 IV. SPECIFIC GRAVITIES OF GASES .... 251 
 V. PHYSICAL CONSTANTS OF THE ELEMENTS . . 252 
 
 VI. VOLUME AND WEIGHT OF WATER FROM TO 
 
 31 C 258 
 
 VII. VAPOR PRESSURE OF WATER FROM TO 
 
 + 100C 259 
 
 VIII. ELECTRO-CHEMICAL EQUIVALENTS . . . . 260 
 
 IX. UNITS OF ELECTRICITY, HEAT, AND POWER . . 261 
 
 X. HEATS OF COMBINATION 262 
 
 XI. SPECIFIC RESISTANCE OF VARIOUS SUBSTANCES . 263 
 
 XII. DENSITIES OF VARIOUS SUBSTANCES . . . 264 
 
 XIII. TABLE OF SOLUBILITIES 266 
 
 XIV. PREPARATION OF SOLUTIONS 271 
 
 XV. STANDARD STOCK SOLUTIONS 275 
 
 XVI. COMPARISON OF CALCULATED AND OBSERVED DECOM- 
 POSITION ; VOLTAGES OF AQUEOUS SOLUTIONS . 278 
 
PROGRESSIVE PROBLEMS IN 
 CHEMISTRY 
 
 CHAPTER I 
 
 Introduction 
 
 MEASUREMENT 
 
 Metric System Linear Measure 
 
 1. Express 263.7018 m. as < dm. ; (b) cm. ; 
 (<?) mm. ; (d) Dm. ; 0) Hm. ; (/) Km. 
 
 2. Express as m. (a) 5 Dm. ; (6) 4 Hm. ; (<?) 9 Dm. ; 
 00 8 Km.; (e) 32 Hm.; (/) 360 cm.; (#) 630 mm. 
 
 3. How many mm. in (a) 13 Km. ; (5) 92 Hm. ; 
 (<0 BOO Dm.; (d) 26.91 m. ; (e) 86.312 dm.; 
 (/) 8 cm.? 
 
 4. In a mile how many Km. ? How many m. ? 
 How many cm. ? 
 
 5. Express 10 yd. in m. ; in Km. ; in Hm. ; in cm. ; 
 in mm. 
 
 6. In 31.76 ft. how many m.? How many Km.? 
 How many cm. ? How many dm. ? 
 
 7. Convert 83 in. into (a) mm.; (&) cm.; (<?) Km.; 
 (<T) Hm, ; ( dm. 
 
 8. Find the value of the following expressions in m. : 
 O) 0.435 m. + 852 cm.-f 4263 mm. + 0.159 Km. ; 
 (b) 0.927 Km. - 6495 cm., 4.37 cm. - 42.87 mm. ; 
 
 l 
 
2 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 (<?) 8 x 0.0457 Km., 3.04 x 60.93 cm., 5.43 x 67.2 mm.; 
 (<f) 38,019 mm. -i- 0.097, 0.14 Km. -*- 25.625. 
 
 9. A book is 2.1 cm. thick; if the average thick- 
 ness of the leaves is 0.05 mm., find the number of 
 pages in the book. 
 
 10. The cost of building a railroad is $ 25,000 per 
 Km.; what is the cost of the road, if its length is 
 72 Km. and 53 in.? 
 
 11. The wheels of a locomotive that make 45 Km. 
 an hour are 7.5 m. in circumference ; how many revo- 
 lutions will they make a minute? 
 
 12. A train goes 1248 m. in 1J min. ; how many Km. 
 will it go in 1 hr., 35 min., and 15 sec.? 
 
 13. The top of a monument is 143.9 m., and the base 
 67.19 m. above the level of the sea; the steps which 
 lead from the base to the top of the monument are 
 each 19 cm. high. How many steps are there? 
 
 14. Sound travels 1130 ft. per second; how many 
 meters does it pass through per second? 
 
 15. It is 92,000,000 miles to the sun ; how many Km. 
 is it? 
 
 16. Light travels 186,000 miles per second ; how many 
 Km. per second is that ? 
 
 17. The mean height of the barometer in the latitude 
 of Greenwich at the level of the- sea is 30 in.; to how 
 many mm. is this equivalent? 
 
 18. How many dm. are equivalent to 106,725 mm.? 
 
 19. How many miles are there in 15 Km.? 
 
 20. In an English inch are contained 25.3995 mm.; 
 how many Km. are there in a mile? 
 
MEASUREMENT 3 
 
 21. A nautical fathom is 6.087 ft. ; what is its value 
 in m. ? 
 
 Surface Measure 
 
 22. Multiply 5 dm. by 3 mm., and give the answer in 
 cm. 
 
 23. Reduce and give the answers to the following in 
 cm. 2 : (a) 1.51 m. x 2.5 dm.; (6) 0.35 m. x 3 cm.; 
 (c) 10 dm. 2 -r-4 cm.; (d) 1.3 m. 2 -T- 3 cm. 
 
 24. Measure the length and breadth of a sheet of paper 
 and give the result in decimeters; then compute how 
 many cm. 2 could be cut from it. 
 
 25. Calculate the number of cm. 2 contained on the 
 surface of a filter paper having a radius of 5 cm. 
 
 26. A round filter paper is 10 cm. across; what is its 
 area? 
 
 27. How many cm. 2 are there in 15.5m. 2 ? How 
 many dm. 2 are contained in 108,642 cm. 2 ? 
 
 28. Required the number of mm. 2 , cm. 2 , dm. 2 , con- 
 tained in the top of a table measuring 1m. x 70 cm. 
 
 29. Reduce the following to cm. 2 : (a) 2.8 dm. 2 ; 
 (5) 3.1dm. 2 ; (c) 1.35m. 2 ; (d) 0.75dm. 2 ; 0) 0.032 m. 2 ; 
 (/) 0.0064dm. 2 ; (<?) 700m. 2 . 
 
 30. Reduce the following to dm. 2 : (a) 53 cm. 2 ; 
 () 7.3cm. 2 ; (c) 0.003 cm. 2 ; (d) 25m. 2 ; < 0.33 cm. 2 ; 
 (/) 28.03 m. 2 . 
 
 31. How many cm. 2 in a square one side of which is 
 (a) 1.7 dm.; (6) 35 dm.; (V) 1 m. ; (d) 0.035 dm.; 
 0) 3.2 dm.? 
 
 32. How many cm. 2 in the following rectangles: 
 (a) 2dm. x 6cm. ; (6) 0.07m. x 7 cm.; (c) 3.2dm. 
 X 0.2 dm. ; '(<f) 58 dm. x 25 cm. ? 
 
4 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 33. Express 1 mm. 2 as (&) the decimal of a cm. 2 ; 
 (6) of a m. 2 ; (c) of a dm. 2 . 
 
 34. Compute the area of a filter paper 12 cm. in dia- 
 meter. 7T = 3.14. 
 
 35. Required the number of (a) cm. 2 , (5) dm. 2 , and 
 (c) m. 2 in 1,098,765,421 mm. 2 . 
 
 36. How many m. 2 in 9 Dm. 2 ; 8 Hm. 2 ; 13 Km. 2 ? 
 
 37. How many ca. in 9 a. ; in a Ha. ? 
 
 38. What part of a Ha. is an a.; a ca. ? 
 
 39. What part of a m. 2 is a dm. 2 ; a mm. 2 ? 
 
 40. Convert 1,854,276 m. 2 into Ha.; into Km. 2 . 
 
 41. Write 1.7431 m. 2 as cm. 2 ; as mm. 2 . 
 
 42. How many Km. 2 in 17,467.5 Ha.? 
 
 43. How many cm. 2 in 0.0137 m. 2 ? 
 
 44. Write 3.571 cm. 2 as mm. 2 . 
 
 45. A man bought 3 Ha. of land at |2.00 per Ha. 
 and sold it for $ 2.50 per a. ; how much did he gain ? 
 
 Volume 
 
 46. A cellar 20 m. x 50 m. x 3 m. is to be excavated; 
 what will it cost at 12 cents per m. 3 ? 
 
 47. How many cc. are there in a block 12 cm. long, 
 8 cm. wide, and 5 cm. high? 
 
 48. How many m. 3 are there in a wall 25 m. long, 
 8.4 m. high, and 76 cm. wide? 
 
 49. A wood pile contains 1800m. 3 ; it is 15m. long 
 and 12 m. wide. How high is it? 
 
 50. How many cm. 2 are there in one face of a cube 
 containing 729 cc. ? 
 
MEASUREMENT 5 
 
 51. A gallon is equal to 3.7851.; how many cc. are 
 contained in one pint ? 
 
 52. Reduce 16 1. to U. S. gallons. 
 
 53. A beaker 6 cm. in diameter and 8 cm. high will 
 hold how many 1. of water? 
 
 54. A pneumatic trough is 3.1 dm. long by 1.9 dm. 
 wide and 1.5 dm. high, (a) How many 1. of water 
 will it hold? (6) How many dl. of water? (Y) How- 
 many cl. ? (cT) How many ml. ? 
 
 55. A cistern 1.42 m. x 8.4 dm. x 53 cm. will hold 
 what weight and volume of water? 
 
 56. A box is 1.2 dm. x 7 cm. x 30 mm. What is 
 the capacity in cc. ; also in 1. ? 
 
 57. Compute the contents of these boxes in 1. and in 
 cc. : (a) 12 cm. x 5 cm. x 4 cm. ; (5) 2.1 dm. x 3.2 dm. 
 X 10 cm.; <V) 1.04 m. x 1.03 m. x 1.02 m. 
 
 58. How many cc. in a slab of marble 1.5 m. x 7 dm. 
 x 9 cm. ? How many 1. of water will such a slab dis- 
 place ? 
 
 59. Reduce the following to cc. : (a) 3.7 dm. 3 ; (5) 
 5.02 dm. ; (<?) 1.001 dm. 3 ; (d) 0.003 dm. 3; (V) 200 
 mm. 3 . 
 
 60. Reduce and express the following as indicated : 
 (a) 2 dm. 3 to mm. 3 ; (5) 5.7 dm. 3 to mm. 3 ; (V) 33.33 
 cm. 3 to m. 3 ; (d) 1.07 dm. 3 to m. 3 . 
 
 61. A stick of timber 4 m. long and 3 dm. wide has 
 a solid contents of 240 dm. 3 ; what is its thickness? 
 
 62. What is the capacity in 1. of a rectangular tank 
 2 m. long, 9 dm. wide, and 8 dm. deep? 
 
 63. What is the volume of a spherical glass bulb 
 which has a radius of 3 cm.? 
 
6 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 64. How many 1. of air are contained in a room 
 measuring 4 m. x 3 m. x 2 m.? 
 
 65. In 1.5 pints there are how many cc.? How many 
 mm. 3 ? 
 
 66. How many 1. of water are contained in a tank 
 3 m. x 1.6 m. x 1.4 m.? 
 
 67. How many HI. in a bin 4 m. x 2 m. x 1 m. ? 
 
 68. How high must a box be to hold 30 1. if it is 50 
 cm. long and 20 cm. wide ? 
 
 69. In a m. 3 , how many dm. 3 ; cc. 3 ? What part 
 of a m. 3 is a dm. 3 ; a cc. 3 ? 
 
 70. How many m. 3 in a rectangular box 125 cm. x 
 112 cm. x 80 cm. ? How many 1. ? 
 
 71. How deep must a cistern be to hold 6000 1. if the 
 bottom is a square measuring 2.25 m. on a side? 
 
 72. How many m. 3 of earth must be removed to dig 
 a ditch 90 m. x 85 cm. x 50 cm. ? 
 
 73. A cistern is 2m. x 1.5 m. x 1 m. ; how many 1. 
 of water will it hold ? 
 
 74. A cylinder of a steam engine is 3 ft. in diameter 
 and 5 ft. long; how many dm. 3 of steam will it contain ? 
 
 Weight 
 
 75. How many g. in 1 Kg.; 8 Dg. ; and 6 Hg. ? 
 What part of 1 g. is 1 eg. ; 1 dg. ; 1 mg.? 
 
 76. In a ton how many Kg. ? How many g. ? 
 
 77. A HI. of water weighs how many Kg. ? What 
 part of a ton ? 
 
 78. Change 0.546 Kg. to g.; to mg.; to eg. 
 
 79. Change 0.391 of a ton to Kg. 
 
MEASUREMENT 7 
 
 80. How many eg. are contained in 2. 567 Kg. ? How 
 many g. are contained in 1.725 Kg. ? 
 
 81. How many eg. are contained in 2.567 Kg.? How 
 many mg. are contained in 5 cc. of water at -f-4C.? 
 
 82. How many mg. are there in 0.9 dg. ? How 
 many in 1 Kg. ? 
 
 83. A cylindrical tube 90 mm. in length holds 1 g. of 
 water at + 4 C. Calculate its internal diameter. 
 
 84. What is the weight of water in a tank 1.3m. 
 x 80 cm. x 250 mm.? 
 
 85. How many g. of water in a bottle containing 
 0.391 1.? 
 
 86. A sample of water contains 4 g. of solid matter 
 per 1. ; to how many g. per gallon does this correspond? 
 
 87. A tank measures 2.5 m. x 3 m. x 6 m. ; how 
 many 1. of water will it hold? How many Kg. ? 
 
 88. A ton equals 1016.05 Kg. ; how many g. in 1 Ib. 
 avoirdupois? 
 
 89. A piece of platinum foil measuring 10.5 cm. by 
 1.5 cm. weighs 0.723 g.; into how many pieces, each 
 weighing 1 dg., may it be divided ? 
 
 90. A fine wire 255 mm. in length weighs 0.172 g.; 
 what length of such wire would it take to make a eg. 
 rider " ? 
 
 91. How much space will 3.750 g. of water occupy? 
 
 92. A piece of Swedish filter paper measuring 60 
 cm. 2 leaves on burning 0.1062 g. of ash. Calculate 
 the amount of ash left on burning filters possessing the 
 following radii: (a) 3 cm.; (5) 4 cm.; (<?) 5 cm.; 
 00 6 cm. ; 0) 8 cm. ; (/) 10 cm. 
 
8 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 93. Required the number of mg. in 115 cc. of water 
 measured at + 4 C. 
 
 94. A silver coin weighs 30 g. ; what volume of 
 water will it balance ? 
 
 95. A piece of platinum foil is 5.2 cm. x 0.7 cm. and 
 weighs 0.8 g. ; into how many pieces, each weighing 
 1J dg., may it be cut? 
 
 96. What weight of water is required to fill a vat 
 98 cm. x 71 cm. x 38 cm.? 
 
 97. A mass of 21.7 g. is divided into 70 pills; what 
 is the weight of each pill? 
 
 98. At 2 cents a Kg., what will 2.25 tons of hay cost? 
 
 99. At $ 6 a ton for coal, what will it cost to heat 
 a building 30 days if it takes 400 Kg. of coal a day ? 
 
 100. Into how many pieces of 325 mg. each may a 
 mass of 23.4 g. be divided ? 
 
 101. A liter of mercury weighs 13 Kg. 598 g.; 
 find the weight in Kg. of 3.69 1. 
 
 102. If 16.94 1. of olive oil weigh 15 Kg. 500 g., find 
 the weight of 1 1. 
 
 Thermometry 
 
 103. What temperature on the C. scale is equivalent 
 to + 250F.? 
 
 104. What temperature C. corresponds to 250 F.? 
 
 105. Change F. to C. 
 
 106. Express + 40 C. on the Fahrenheit scale. 
 
 107. Convert the following temperatures to C.: 
 + 40 F., + 2100 F., - 70 F., 
 - 40 F., - 28 F., + 2700 F. 
 
MEASUREMENT 9 
 
 108. Express the following temperatures in F. : 
 
 + 125 C., + 60 C., + 312 C., 
 
 + 15 C., + 480 C., - 273 C. 
 
 109. A Fahrenheit thermometer, immersed in a cer- 
 tain hot fluid, rises through -f- 50 ; through how 
 many degrees would a Centigrade thermometer have 
 risen under the same circumstances ? 
 
 no. What is the difference in temperature between 
 + 72 C. and + 72 F. ? 
 
 111. What temperature on the Centigrade scale is 
 equal to + 212 F. ? 
 
 112. Express the following temperatures in C. : 
 + 60F., -15.5F., +0.2F. 
 + 10 F., + 500 F., 
 
 113. Express the following temperatures in F. : 
 
 + 4 C., + 60 C., + 212 C., 
 
 + 15.5C., +0.1C., +1C. 
 
 114. Reduce the following Centigrade degrees to the 
 Absolute scale : 
 
 + 37C., +26C., +273C., +11C., - 12 C., 
 + 55 C., + 18 C., + 40 C., - 40 C. 
 
 115. Reduce the following Fahrenheit degrees to the 
 Absolute scale : 
 
 + 25 F., + 60 F., + 1 F., - 8 F., - 30 F. 
 
 116. Reduce the following Fahrenheit temperatures 
 to the Centigrade scale : 
 
 + 68 F., + 36 F., + 30 F., + 32 F., F., - 40 F., 
 - 44 F. s - 36 F., + 10 F., - 10 F., - 1 F. 
 
10 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 117. Reduce the following Centigrade degrees to 
 Fahrenheit : 
 
 + 72 C., + 36 C., C., + 4 C., -4 C., - 40 C., 
 + 40 C., - 273 C., + 273 C., - 1 C., + 1 C. 
 
 118. What must be the temperature of a liquid so 
 that both the Fahrenheit and Centigrade thermometers 
 shall read the same when immersed in it ? 
 
 119. Reduce + 8 C., + 20C., + 70 C., - 40 C., 
 and +10 C. to the Fahrenheit scale. 
 
 120. Reduce + 8 F., +40 F., + 180 F., - 10 F., 
 and + 36 F. to the Centigrade scale. 
 
 121. Change these to the Absolute scale : 
 
 + 79 F., + 79 C., + 31 C., - 60 C., - 5 C. 
 
 122. Sulphuric acid boils at -f- 338 C. ; what is the 
 corresponding boiling point on Fahrenheit's scale ? 
 
 123. Cast iron melts at + 2822 F. and tin at 
 + 455 F. ; what is the difference between their melt- 
 ing points expressed in Centigrade degrees ? 
 
 124. Bromine boils at +138.7F. ; what is the cor- 
 responding temperature on the Centigrade scale ? 
 
 125. Absolute zero is 273 below zero on the Cen- 
 tigrade scale; what is this temperature on the Fahren- 
 heit scale? 
 
 126. Iron melts at + 1200 C. ; what is the melting 
 point on the Fahrenheit scale? 
 
 127. The average difference in temperature between 
 two places is + 60 F. ; how much would this be on the 
 Centigrade scale ? 
 
 128. A low artificial temperature obtained is 140 C . ; 
 what is the corresponding temperature in F. degrees ? 
 
MEASUREMENT 11 
 
 129. Chloroform boils at +61.2 C., turpentine boils 
 at 4- 156C., and glycerine boils at+290C.; what are 
 the Fahrenheit readings? 
 
 130. At a certain temperature C. scale the reading is 
 as much below 0.C. as it is above on the F. scale. 
 Find the readings. 
 
 131. Ether boils at + 34.5 C., alcohol at + 78.4 C., 
 and sulphuric acid at + 338C. ; what are the corre- 
 sponding boiling points on Fahrenheit's scale ? 
 
 132. Mercury freezes at - 40 C. and boils at + 350 C. 
 Calculate the corresponding temperatures on the scales 
 of Reaumur and Fahrenheit. 
 
 133. Cast iron melts at +1075 C., zinc at +423 C., 
 lead at + 334 C., tin at +235 C. Calculate these tem- 
 peratures in F. degrees. 
 
 134. The difference between readings on C. and F. 
 scale is 64. Find the reading. 
 
 Specific G-ravity of Solids and Liquids 
 
 135. A piece of metal weighs 24.076 g. in air and 
 21. 2436 g. in water; what is its sp. gr. ? 
 
 136. A piece of mineral weighs 47 g. in air and 36.555 
 g. in water; what is its sp. gr. ? 
 
 137. A piece of iron ore weighs 27 g. in air and 21.6 g. 
 in water ; what is its sp. gr. ? 
 
 138. A certain fine powder weighs in the air 7 g. ; when 
 this powder is placed in a flask, and this flask is then 
 filled with water to a mark on the flask, the weight of 
 the flask, powder, and water to the mark is 59 g. The 
 weight of the flask filled with water only to the mark 
 is 55 g. What is the sp. gr. of the insoluble powder? 
 
12 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 139. A certain fine sand weighs 12 g. in the air. A 
 flask filled with water to mark weighs 47. 6 g. The 
 same flask containing the sand and filled to the same 
 mark with water weighs 56. 5 g. What is the sp. gr. of 
 the sand? 
 
 140. An empty bottle weighing 3. 5305 g. weighs when 
 filled with pure water 7. 6722 g., when filled with sea- 
 water 7. 7849 g. What is the sp. gr. of sea water? 
 
 141. A sample of sugar weighs 7.5 g. in the air and 
 4.6g. in petroleum ether of sp. gr. 0.64; what is the 
 sp. gr. of the sugar ? 
 
 142. Find the sp. gr. of common salt from the follow- 
 ing data : weight of salt in air, 8.85 g. ; weight of flask 
 and turpentine to mark, 45.24 g. ; weight of flask, salt, 
 and turpentine to mark, 50.56 g.; sp. gr. of turpentine, 
 0.86 g. 
 
 143. Find the relative densities of the following sub- 
 stances: 
 
 Granite Marble Hematite 
 
 Weight in air 409.82 g. 53.2841 g. 13.6287 g. 
 4 * water 259. 31 g. 33.4020 g. 10.9406 g. 
 
 144. A sp. gr. flask holds 2.545 mg. of alcohol, 
 42.740 of mercury, and 5.829 of sulphuric acid. Calcu- 
 late the relative density of the sulphuric acid and 
 mercury, the density of the alcohol being 0.80. 
 
 145. A solid weighs in a vacuum 100 g. ; in water 
 85 g.; and in another liquid 88 g. What is the relative 
 density of this liquid? 
 
 146. Determine the relative density of gold from 
 the following data : 
 
 Weight of gold in air 4.6764 g. 
 
 Loss of weight in water 0.2447 g. 
 
MEASUREMENT 13 
 
 147. A glass rod weighing 13 g. in air weighs 8 g. 
 in water and 3.8 g. in sulphuric acid; what is the sp. gr. 
 of the sulphuric acid ? 
 
 148. A piece of iron sulphide weighed in air 4.8934 g. ; 
 in water it weighed 3.8860 g. Calculate its relative 
 density. 
 
 149. Find the weight of a block of sulphur 50 m. 3 in 
 Yolume and of relative density 2.05. 
 
 150. What is the weight of 1 1. of bromine, sp. gr. 
 3.19; of burning oil, sp. gr. 0.83; of alcohol, sp. gr. 
 0.80; of mercury, sp. gr. 13.59? 
 
 151. What is the volume of 1 Kg. of iron, sp. gr. 
 7.85; of magnesium, sp. gr. 1.74; of platinum, sp. gr. 
 21.5; of ice, sp. gr. 0.92? 
 
 152. A bottle holds 336 g. of water; it also holds 
 577.9 g. of sulphuric acid. What is the sp. gr. of the 
 acid? 
 
 153. A bottle weighs 80 g. when empty. Filled 
 with water it weighs 230 g. Filled with bromine it 
 weighs 560 g. ; with hydrochloric acid, 260 g. What is 
 the sp. gr. of the bromine and of the acid ? What is 
 the capacity of the bottle? 
 
 154. A bar of gold measures 34 by 10.5 by 11 cm., 
 
 and weighs 75.87 Kg.; what is the sp. gr. of the gold? 
 
 155. A block of wood measures 49.8 by 60.5 by 210. 
 cm.; its sp. gr. is 0.63. What is the weight of the 
 block? 
 
 156. What is the weight of a m. 3 of bromine, sp. gr. 
 3.19; of water at +4 C.; of sulphuric acid, sp. gr. 1.84? 
 
 157. The sp. gr. of HNO 3 is 1.52. (a) Find weight 
 of 20 cc. ; (5) 87 cc. ; (V) how many cc. in 100 g. ? 
 
14 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 158. What is the weight of 40 cc. of sulphuric acid 
 having a sp. gr. of 1.84? 
 
 159. What is the volume of 3.6 Kg. of alcohol having 
 asp.gr. of 0.80? 
 
 160. A piece of metal weighs 3.7395 g. in air, 1.578 g. 
 in water, and 2.2896 g. in another liquid; what is 
 the sp. gr. of the metal and of the liquid? 
 
 161. A piece of platinum foil 14.2 cm. long and 2.5 
 mm. broad weighs 12 g.; find the thickness. Density 
 of platinum = 21.5. 
 
 162. A body weighing 18.5 g. when under water 
 weighs 16.4 g. and when in naphtha 16.72 g. ; what is 
 the sp.gr. of the naphtha? 
 
 163. Find the mass of 1 m. 3 iron. Sp. gr. Fe = 7.80. 
 
 164. A mercury barometer stands at 76.1 mm.; what 
 would be the reading on a glycerine barometer? 
 Sp. gr. glycerine is 1.26, mercury is 13.59. 
 
 165. Nitric acid being 1.52 times as heavy as water, 
 what is the weight of 1 1. of the acid ? 
 
 166. A piece of sodium weighed 14.1563 g. in dry 
 air and 2.1807 g. in kerosene of sp.gr. 0.83; what is 
 the sp. gr. of sodium ? 
 
 167. A piece of metal weighs 47 g. in water and 
 48.756 g. in petroleum ether of sp. gr. 0.66; what is 
 the sp. gr. of the metal ? 
 
 168. A piece of brass weighs 10 g. in air, 8.824 g. in 
 water, and 9 g. in turpentine. Calculate the sp. gr. of 
 the turpentine. 
 
 169. If sulphuric acid has a sp. gr. of 1.84, how many 
 cc. of it will weigh 80 g. ? 
 
MEASUREMENT 15 
 
 170. A block of marble 5cm. x 4cm. x 3cm. has a 
 sp. gr. of 2.7; how many g. will it weigh? 
 
 171. A lump of sodium carbonate (sp. gr. = 1.45) 
 is 65mm. x .4dm. x 3cm.; what does it weigh? 
 
 172. The sp. gr. of sulphuric acid is 1.84. A carboy 
 holds 5 gal. of 231 in. 3 each. How heavy would the 
 contents of this carboy be? 
 
 173. What is the densit}^ of a cube of oak 9 mm. 
 along each edge and which weighs 0.62g.? 
 
 174. A cylinder of mahogany 10.1cm. high and 
 9.4 cm. across weighs 405.7 g. Find its density. 
 
 175. A block of steel (sp. gr. = 7.6) is 10 cm. square 
 and 1.8315 cm. thick. Find the mass of it in g. 
 
 176. What is the mass of a m. 3 of hematite (sp. gr. 
 = 5.25)? 
 
 177. Find the volume of 1000 g. of sea water (sp. gr. 
 = 1.03). 
 
 178. Find the mass of a m. 3 of anthracite (sp. gr. 
 = 1.4). 
 
 179. How many tons does a block of granite (sp. gr. 
 = 2.7) 10 x 3 x 2m. weigh? 
 
 180. If a glass ball weighing 7.7158 g. 2 cm. in diam- 
 eter just floats in a liquid, find the sp. gr. of the 
 liquid. 
 
 181. What is the density of K 2 Cr 2 O 7 , if 6. 2138 g. of 
 it displace 2.0532 g. of benzene (sp. gr. = 0.88)? 
 
CHAPTER II 
 
 Molecular Weights from Atomic Weights 
 MOLECULAR WEIGHTS 
 
 Calculate the molecular weights of the following: 
 
 1. HC 2 H 3 2 ; AlBr 3 ; A1 4 C 3 ; A1 2 O 3 ; A1I 3 ; 
 A1(N0 3 ) 3 ; A1P0 4 ; A1 2 (SO 4 ) 3 ; K 2 A1 2 (SO 4 ) 4 ,24 H 2 O. 
 
 2. NH 4 C1; (NH 4 ) 2 C0 3 ; NH 4 HCO 3 ; (NH 4 ) 2 CrO 4 ; 
 NH 4 CN; NH 4 F; (NH 4 ) 2 MoO 4 ; NH 4 NO 3 ; NH 4 NO 2 . 
 
 3. NH 4 C1O 4 ; NH 4 H 2 P0 4 ; (NH 4 ) 2 S ; NH 4 CNS; 
 (NH 4 ) 2 W 4 13 ,8H 2 0. 
 
 4. SbBr 3 ; SbH 3 ; Sb 2 O 3 ; SbOCl; Sb 2 S 3 ; 
 H 3 AsO 4 ; As 2 O 3 . 
 
 5. AuCl 3 ; Au 2 O 3 ; Au 2 S 3 ; AuBr 3 ; Au 2 O ; 
 Ba(C 2 H 3 2 ) 2 , H 2 ; BaCO 3 . 
 
 6. BaCrO 4 ; BaF 2 ; BaSO 4 ; BiBr g ; BiONO 3 ; 
 Bi 2 S 3 ; H 3 B0 3 ; B 6 C. 
 
 7. BrCl,10H 2 0; CdSO 4 ; CdO ; CdS ; Cd(NO 3 ) 2 ; 
 Cd(CN) 2 ; CdWO 4 ; CsCl; CsBr; Cs 2 S 5 . 
 
 8. CaCO 3 ; CaAl 2 O 4 ; Ca(HCO 3 ) 2 ; CaO; 
 Ca(ClO 3 ) 2 ; CaF 2 ; Ca(OH) 2 ; CaI 2 ; CaSO^; CO 2 . 
 
 9. C 2 Br 4 ; C 2 C1 4 ; CS 2 ; CO. 
 
 10. CeC 2 ; Ce(NO 3 ) 4 ; CeO 2 ; CeCl 3 ; C1 2 O; C1 2 O 7 ; 
 Cr0 3 ; CrCl 3 ; Cr 2 (SO 4 ) 3 . 
 
 16 
 
MOLECULAR WEIGHTS 17 
 
 11. CrO 2 Cl 2 ; Co 2 P; CoCl 2 ; Co(NH 3 ) 6 Cl 3 ; 
 Co(OH) 3 ; CbBr 5 ; CbH ; CbN; Cb(HC 2 O 4 ) 5 ; 
 CbOBr 3 ; Cb 2 OS 3 . 
 
 12. CuBr 2 ; Cu 2 O; CuSO 4 ,5H 2 O; CuCO 3 ; CNOH; 
 C 2 N 2 ; ErCl 3 ,6H 2 0; Er 2 O 3 ; Er 2 (SO 4 ) 3 . 
 
 13. FeAsO 4 ,2H 2 O; FeCl a ; FeCl 3 ; FeCO 3 ; Fe 3 O 4 ; 
 
 FeS. 
 
 14. Ga 2 (SO 4 ) 3 ; Ga 2 S 3 ; GeBr 4 ; GeOCl 2 ; BeCO 3 ; 
 BeF 2 . 
 
 15. Au 2 P 3 ; NH 2 ,NH 2 ; HC1 ; HCN ; H 2 O 2 ; NH 2 OH ; 
 InBr 3 ; InCl 3 . 
 
 16. In(CN) 3 ; HIO 3 ; Id; IrI 3 ; IrS 2 ; Fe 3 C , 
 LaC 2 ; La 2 O 3 ; La 2 (SO 4 ) 3 ; La 2 S 3 . 
 
 17. Pb(C 2 H 3 2 ) 2 ; Pb(B0 2 ) 2 ,H 2 0; PbBr 2 ; 
 Pb(N0 3 ) 2 ; PbO; Pb 3 O 4 . 
 
 18. PbO 2 ; LiBr; LiOH ; LiNO 3 ; Li 2 C 2 O 4 ; Li 2 O ; 
 MgC0 3 . 
 
 19. MgF 2 ; MgSO 4 ,7H 2 O; MnCl 2 ; Mn(OH) 2 ; 
 HgCl 2 ; HgS0 4 . 
 
 20. HgCl; HgS; MoC ; MoCl 3 ; MoS a ; NdCl 3 , 
 6 H 2 ; NdC 2 . 
 
 21. NiAs; Ni(C 2 H 3 O 2 ) 2 ; NiCO 3 ; HNO 3 ; N 2 ; 
 N 2 0; NOC1. 
 
 22. OsCl 2 ; OsO 4 ; OsS 2 ; O 2 ; PdBr 2 ; Pd(CN) 2 ; 
 PdS0 4 , 2 H 2 0. 
 
 23. PF 3 ; PBr 2 N; Pt 2 O 3 ; PtBr 2 ; K 2 A1 2 O 4 , 3 H 2 O; 
 K 2 PtCl 4 ; KOH; PrCl 3 . 
 
 24. Pr 2 S 3 ; RaBr 2 ; RaC] 2 ; RhCl 3 ; Rh(SH) 3 ; 
 Rh(OH) 3 ; RbBr; Rb 2 CO 3 ; RbF ; RbOH. 
 
18 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 25. RuCl 2 ; Ru(OH) 3 ; Ru 2 O 3 ; SmC 2 ; Sm(NO 3 ) 3 , 
 6 H 2 ; Sc 2 3 . 
 
 26. Sc 2 (SO 4 ) 3 ; Se 2 Br 2 ; SeCl 2 ; SeOCl 2 ; SiHBr 3 ; 
 SiF 4 . 
 
 27. AgC 2 H 3 2 ; AgBr0 3 ; AgCl; Ag 2 Se ; Ag 2 S ; 
 NaCl; Na 2 SO 4 . 
 
 28. NaNO 3 ; NaHCO 3 ; NaAuCl 4 , 2 H 2 O ; Na 8 VO 4 , 
 16H 2 O; Na 2 WO 4 , 2 H 2 O. 
 
 29. SnO 2 ; Sn 2 Fe(CN) 6 ; SnF a ; SrBr 2 ; SrC 2 ; 
 Sr(Br0 3 ) 2 ,H 2 0; H 2 SO 4 ; SOBr 2 ; TaBr 5 . 
 
 30. Ta 2 5 ; H 2 C 4 H 4 6 ; TeO 2 ; Tb 2 O 3 . 
 
 31. T1F; T10H; T1(NO 3 ) 3 ; ThBr 4 ; Th(C 2 O 4 ) 2 ; 
 Ti 6 (CN) 4 ; Ti 2 3 . 
 
 32. WBr 2 ;W 2 C; WC1 4 ; WO 2 ; H 2 WO 4 ; H 2 UO 4 ; 
 U 2 C 3 . 
 
 33. U0 2 C1 2 ; HV0 3 ; VF 3 , 3 H 2 O ; Yb(C 2 H 3 O 2 ) 3 , 
 2H0 2 ; Yb 2 3 ; Yb 2 (SO 4 ) 3 ; YtBr 3 ; Yt(NO 8 ) 8 , 
 4H 2 0. 
 
 34. ZnF 2 ; Zn 2 Fe(CN) 6 , 3 H 2 O ; ZnSO 4 ,6H 2 O; 
 ZrBr 4 ; Zr(OH) 4 ; ZrOCl a , 8 H 2 O ; Zr(SO 4 ) 2 , 4 H 2 O. 
 
 35. What are the molecular weights of the minerals 
 having the following formulas: (Ag 2 Pb)Se; (AgCu) 2 S ; 
 Cu a Se ; (PbHg 2 )Se ; (PbCuAg 2 )Se ; Hg(SSe) ; 
 (HgZn)S; NiSb. 
 
 36. Ni(SbAs); Fe 16 S 16 ; CoS 2 ,CoAs; PtAs 2 ; 
 RuS 2 ; FeS 2 ,FeAs; NiS 2 ,Ni(AsSb) 2 ; Cu 2 S,Bi 2 S 3 ; 
 MnS 2 . 
 
 37. 9Ag 2 S,Sb 2 S 3 ; Ag(ClBrl); (FeMg)O,TiO 2 ; 
 MnO,Ti0 2 ; MgO,Al a O 8 ; (FeMg)O,Fe 2 O 3 ; FeO, 
 Cr 2 3 . 
 
MOLECULAR WEIGHTS 19 
 
 38. Mn 2 3 ,H 2 0; (CaBa)CO 3 ; CaCO 3 , (MgFe)CO 3 ; 
 KAlSi 3 8 ; (K 2 Ba)Al 2 Si 4 12 ; (NaK)AlSi 3 O 8 . 
 
 39. CaAlSi 2 O 8 ; BaAl 2 Si 2 O 8 ; H 2 Cs 4 Al 4 (SiO 3 ) 9 ; 
 NaFe(SiO 3 ) 2 ; HNaCa 2 (SiO 3 ) 3 ; (MnZnFeCa)SiO 3 . 
 
 40. (K 2 Na 2 MgCaMn) 4 (SiO 3 ) 4 ; NaAl(SiO 3 ) 2 , 
 (FeMg)Si0 3 ; K 2 Na 6 Al 8 Si 9 O 34 ; 
 
 (NaK) 10 Ca 4 Al 12 Si 12 52 SCl 4 . 
 
 41. Na 4 (NaS 3 , Al)Al 2 (Si0 4 ) 3 ; Bi 4 (SiO 4 ) 3 ; 
 Ca 3 Al 2 (SiO 4 ) 3 ; (FeZnMn) 2 [(ZnFe) 2 S]Be 3 (SiO 4 ) 3 ; 
 
 Ca 3 Cr 2 (Si0 4 ) 3 . 
 
 42. HCaBSiO 6 ; HBeAlSiO 5 ; Be 2 Fe(YO) 2 (SiO 4 ) 2 ; 
 (CaFe) 2 (A10H)(AlCeFe) 2 (Si0 4 ) 3 ; CaB 2 (SiO 4 ) 2 . 
 
 43. [Mg(FOH)] 2 Mg 3 (Si0 4 ) 2 ; (Na 2 Ca)Al 2 Si 6 O 16 , 
 6 H 2 ; CaAl 2 Si 3 10 , 5 H 2 O; 
 
 44. H 2 KAl 3 (SiO 4 ) 3 ; KLi[Al(OHF) 2 ] Al(SiO 3 ) 3 ; 
 [HK(MgFe)] 3 Mg 3 Al(Si0 4 ) 3 ; (PbCl)Pb 4 (VO 4 ) 3 . 
 
 45. (MnOH)MnAs0 4 ; (MgF)MgPO 4 ; 
 (PbZn) 2 (OH)V0 4 ; (PbZnCu) 2 (OH)VO 4 ; 
 
 Zn 3 As 2 O 8 , 8H 2 O. 
 
CHAPTER III 
 
 Percentage Composition 
 
 1. Find per cent of potassium in (#) KBr ; (5) 
 KNO 3 ; O) K 2 S0 4 ; (d) K 2 S. 
 
 2. Calculate the percentage of oxygen by weight in 
 mercuric oxide, manganese dioxide, potassium chlorate, 
 and water. 
 
 3. In borax (Na 2 B 4 O 7 , 10 H 2 O) find the percentage 
 O) of B ; (6) of Na ; (c) of O ; (d) of H 2 O. 
 
 4. Calculate the percentage composition of CaCO 3 , 
 CaC 2 , CaCl 2 , CO 2 , MgCO 3 , Na a CO 8 , and CO. 
 
 5. What is the per cent of tin in tinstone (SnO 2 ), 
 in SnCl 4 , and in SnCl 2 ? 
 
 6. Calculate the percentage composition of the fol- 
 lowing compounds : 
 
 Potassium ferrocyanide. . . . K 4 Fe(CN) 6 , 3 H 2 O. 
 
 Iso-creatine C 4 H 9 N 3 O 2 . 
 
 Rosaniline C 20 H 21 N 3 O. 
 
 Strychnine C 21 H 22 N 2 O 2 . 
 
 7. The skeleton of a man weighs 24 Ib. and con- 
 tains 58 per cent of calcium phosphate [Ca 3 (PO 4 ) 2 ]. 
 Find the quantity of phosphorus present. 
 
 8. How much phosphorus can be obtained from 169 
 tons of bones containing 53.7 per cent of calcium phos- 
 phate ? 
 
 20 
 
PERCENTAGE COMPOSITION 21 
 
 9. Find the percentage composition of crystallized 
 hydrogen disodium phosphate (Na 2 HPO 4 , 12H 2 O). 
 
 10. Find the per cent by weight of the elements 
 called for in the following: (#) per cent of oxygen in 
 HgO ; (5) of hydrogen in HC1 ; (<?) of lead in PbS ; 
 (d) of lead in Pb(NO 3 ) 2 ; (e) of each element in 
 Ca 3 (P0 4 ) 2 . 
 
 11. Find the percentage composition of H 3 PO 4 to 
 one decimal place. 
 
 12. Find the percentage composition of ammonium 
 nitrate. 
 
 13. A sample of copper salt weighing 0.9864 g. is 
 dissolved in water and the copper deposited electrolyt- 
 ically. The weight of the electrode before passing the 
 current was 9.8609 g. ; at the end of the operation 
 10.1121 g. Find the per cent of copper in the sample. 
 
 14. Which is the richer in iron, Fe 2 O 3 (hematite) or 
 Fe 8 O 4 (magnetite) ? Compute. 
 
 15. Find the percentage composition of alcohol, 
 C 2 H 6 0. 
 
 16. What per cent of sulphur is contained in pure 
 pyrite ? 
 
 17. Compute the percentage composition of Fe 3 O 4 to 
 one decimal place. 
 
 18. Calculate the percentage of silica in potash mica 
 (KHAlSi0 4 ). 
 
 19. What per cent of silicon is in quartz ? 
 
 20. What per cent of magnesium is contained in 
 crystallized potassium magnesium sulphate, K 2 SO 4 , 
 MgSO 4 , 6H 2 O? 
 
22 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 21. What weight of potassium can be obtained from 
 20 g. of alum [K 2 A1 2 (SO 4 ) 4 , 24 H 2 O] ? 
 
 22. Find the percentage composition of bleaching 
 powder if its formula is Ca(OCl 2 ). 
 
 23. 100 g. of each variety of sodium carbonate 
 (a) Na 2 CO 3 , 10 H 2 O ; (ft) Na 2 CO 3 , 8 H 2 O ; (c) Na 2 CO 3 , 
 5 H 2 O ; (<T) Na 2 CO 3 , H 2 O contain how many g. of 
 water ? 
 
 24. What is the percentage of () barium oxide in 
 wither! te; (6) strontium oxide in strontianite; (c) zinc 
 oxide in calamine ? 
 
 25. Calculate the percentage composition of the 
 following compounds: carbon dioxide ; ammonia ; ferric 
 oxide ; acetic acid ; calcium sulphate ; cream of tartar ; 
 ferrous sulphate; common alum. 
 
 26. Calculate the percentage composition of cane 
 sugar and of glucose. 
 
 27. Calculate the percentage of water of hydration 
 in crystalline cupric sulphate. 
 
 28. What are the percentage compositions of sub- 
 stances possessing the following formulas : Mn 3 O 4 , 
 NaCl, and SiF 4 ? 
 
 29. Calculate the percentage composition of propy- 
 lene (C 3 H 6 ) and propane (C 3 H 8 ). 
 
 30. Find the per cent of carbon in (CL) CH 4 ; (b) C 2 H 2 ; 
 00 C 2 H 4 ; 09 COS; () C 4 H 10 ; (/) C 6 H 10 O 5 . 
 
 31. Calculate the percentage composition of the 
 following compounds: 
 
 Water, Calcium carbonate, 
 
 Potassium chlorate, Silver chloride, 
 
 Mercuric oxide, Magnesium pyrophosphate, 
 
PERCENTAGE COMPOSITION 23 
 
 Potassium nitrate, Potassium platinum chloride, 
 
 Sodium nitrate, Sodium thiosulphate, 
 
 Barium sulphate, Magnetic oxide of iron. 
 
 32. How much weight will 32.2 g. crystallized sodium 
 sulphate lose on heating? 
 
 33. How many Ib. of dry Na 2 CO 3 is contained in a 
 Ib. of crystallized washing soda? 
 
 34. How many Ib. of plaster of Paris can be made 
 by calcining 10 Kg. of gypsum ? 
 
 35. What is the percentage of sodium in Glauber's 
 salt? 
 
 36. How many g. of C and of S are contained in 
 1292 g. of CS 2 ? 
 
 37. It is required to find the weight of iron in 1000 
 Kg. of ferric oxide. 
 
 38. How many g. of copper in 3 Kg. of Scheele's 
 green (CuHAsO 3 )? 
 
 39. What weight of Ca, P, and O are contained in 
 100 g. bone ash ? 
 
 40. How much oxygen in 10 g. lime ; 6 g. litharge ; 4 
 g. nitric acid; 10 g. sand? 
 
 41. How many g. of sodium in J ton of NaNO 3 ? 
 
 42. How many g. of mercury in 20 g. of (#) corrosive 
 sublimate; (>) 26 g. calomel; (c) 13 g. mercuric sul- 
 phide ? 
 
 43. How much sodium in (a) 10 g. NaOH; (6) 6 g. 
 Na 2 S0 4 ; < 14 g. NaCl; (d) 2 g. NaHSO 4 ? 
 
 44. Find the percentage composition of (CL) galena; 
 (&) zinc blende. 
 
 45. Find the percentage composition of Cu(NO 3 ) 2 ; 
 Pb(N0 3 ) 2 . 
 
24 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 46. It was found by experiment that 10 g. of crys- 
 tallized sodium sulphate contained 4.70 g. of water; 
 how many molecules of water of hydration does the 
 crystallized salt contain? 
 
 47. What is the percentage of copper in crystallized 
 copper sulphate? 
 
 48. What is the percentage of nitrogen in "caliche" 
 that is 97.8 per cent pure? 
 
 49. A room 15 ft. long and 10 ft. wide and high is 
 covered with a paper containing 0.78 g. of Scheele's 
 green per ft. 2 . How much arsenic is there in the 
 room ? 
 
 50. How many g. of Pb is contained in each of the 
 following: (a) 10 g. litharge; (b~) 10 g. minium; (Y) 
 10 g. lead peroxide ? 
 
 51. Which is cheaper, Na 2 B 4 O 7 , 10 H 2 O at 7 cents a 
 pound, or the anhydrous salt at 5 cents a pound ? 
 
 52. How many Kg. of water will be set free when 
 1 ton of crystallized copper sulphate is converted into 
 the anhydrous condition on heating ? 
 
 53. How much copper in (#) 10 g. Cu 2 O ; (5) 
 13 g. azurite [2 CuCO 3 , Cu(OH) 2 ] ; (<?) 2 g. CuS ? 
 
 54. What is the weight of Ca in 3 g. of calcium 
 sulphate ? 
 
 55. One g. of soft coal on analysis gave 0.0593 g. of 
 barium sulphate. What is the percentage of sulphur 
 in the sample of coal ? 
 
 56. How much arsenic is there in 3 g. of magnesium 
 arsenite ? 
 
 57. Five g. of galena gave on analysis 5 g. of lead 
 sulphate. What is the percentage of lead ? 
 
PERCENTAGE COMPOSITION 25 
 
 58. How many pounds of red lead can be made from 
 500 Ib. of litharge ? 
 
 59. How much anhydrous salt in a Kg. of crystalline 
 (a) copper sulphate ; (6) washing soda ; (c) Epsom 
 salts ; (d) alum ; (e) Glauber's salt ? 
 
 60. Find the g. of lead in (a) 21 g. PbO 2 ; (6) 13 g. 
 PbSO 4 ; (V) 14 g. sugar of lead; (d) 91 g. cerussite 
 (PbC0 3 ). 
 
 61. How much (1) oxygen, (2) chlorine, can be 
 obtained from 100 g. bleaching powder ? 
 
 62. How many pounds of phosphorus in 265 pounds 
 of calcium phosphate ? 
 
 63. What weight of barium sulphate can be obtained 
 from 10 g. of crystallized magnesium sulphate ? 
 
 64. Calculate the percentage composition of Na 2 S 2 O 3 , 
 5 H 2 O ; find the number of g. of water in 17 g. of the 
 salt. 
 
 65. Find the percentage of hydrogen in (a) HC1; 
 (5) H 2 S ; 0) NH 3 ; (d) CH 4 ; (e) HF. 
 
 66. KC1O 3 is 39 <jo oxygen ; calculate the g. of oxygen 
 in (a) 76 g. ; (6) 276 g. ; and (c) 700 g. 
 
 67. A sample of air consists of 12.37 g. N and 3.63 
 g. O. Find the percentage of each. 
 
CHAPTER IV 
 
 Changes in Volume 
 
 Due to (/) changes in pressure alone ; 
 
 changes in temperature alone; 
 
 changes in both temperature and pressure. 
 
 I. Changes in volume due to difference in pressure. 
 
 1. The pressure on 134 cc. of air is increased from 
 480 mm. to 1200 mm. Find the new volume. 
 
 2. The pressure of 240 cc. of nitrogen is increased 
 from 720 mm. to 780 mm. Find the new volume. 
 
 3. The pressure of 25 1. HC1 is decreased from 863 
 mm. to 621 mm. Find the new volume. 
 
 4. The pressure of 15 1. of oxygen is increased from 
 700 mm. to 800 mm. Find the new volume. 
 
 5. The pressure on 10 cc. of gas is 7 m. ; if the 
 pressure is reduced to 847 mm., what is the new vol- 
 ume? 
 
 6. The pressure of 1000 cc. of a gas is decreased 
 from 774 mm. to 600 mm. Find the new volume. 
 
 7. The pressure of 512 cc. of hydrogen is increased 
 from 744 mm. to 790.5 mm. Find the new volume. 
 
 8. The barometric pressure of 5000 cc. of hydrogen 
 is increased from 740 mm. to 760 mm. Find the new 
 volume. 
 
 26 
 
CHANGES IN VOLUME 27 
 
 9. Reduce the following volumes to the volume oc- 
 cupied at standard pressure : () 221 cc. at 963 mm. ; 
 (ft) 30 cc. at 662 mm. ; (V) 100 1. at 1461 mm. 
 
 10. Under standard conditions 1 1. of oxygen weighs 
 1.4336 g. ; what is the pressure when 1 1. weighs 1.29 g. 
 
 11. Under a pressure of 745 mm. 1500 cc. of a gas 
 weigh 1.9762 g. ; what is the weight per 1. under 
 standard pressure? 
 
 12. A body of gas occupies 2000 cc. when the ba- 
 rometer stands at 750 mm. What volume, at the same 
 temperature, will it occupy at 760 mm.? 
 
 13. I have 4-| 1. oxygen under a pressure of 750 mm. 
 At 730 mm., what space will it fill? 
 
 14. At 850 mm., what should be the volume of a gas 
 which at 600 mm. fills 100 cc. ? 
 
 15. What volume will the same gas occupy at 200 
 mm. pressure? 
 
 16. One 1. of air at normal pressure and temperature 
 weighs 1.293 g. Under what pressure will the same 
 volume weigh 2 g. ? 
 
 17. CO has a volume of 18 1. at a pressure of 500 
 mm. Find volume at 650 mm. 
 
 18. If 27 1. of gas at 690 mm. now occupy 31 1., 
 what is the new pressure? 
 
 19. A balloon containing 1200 cm. 3 of coal gas under 
 a pressure of 770 mm. ascends until the barometer 
 stands at 530 mm. What volume would the gas in the 
 balloon now occupy, supposing none to have escaped ? 
 
 20. A certain volume of air preserved at a constant 
 temperature measures 150 cc. when the barometer 
 stands at 760 mm. On the following day its volume 
 
28 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 is found to have decreased 1.52 cc. Calculate the al- 
 teration in the height of the barometer which must 
 have ensued. 
 
 21. What will be the excess of pressure inside a 
 bottle of soda water when four volumes of carbon di- 
 oxide are dissolved in one volume of water? 
 
 22. A volume of hydrogen measuring 195 cc. when 
 the barometer stood at 740 mm. was afterward found 
 to measure 200 cc. What was the height of the ba- 
 rometer at that time ? 
 
 23. A flask having a capacity of 4.5 1. is filled with 
 a gas when the barometer stands at 755 mm. What 
 would be the volume of the same gas in cc. when the 
 barometer stands at 762 mm. ? 
 
 24. A volume of hydrogen in a bell jar over mercury 
 measured 524 cc. The mercury in the jar was 54 mm. 
 above the surface of the mercury in the trough, and the 
 barometer stood at 745 mm. What would have been 
 the volume if exposed to the standard pressure alone? 
 
 25. A volume of gas was found to be equal to 250 
 cc. when the height of the barometer was 742 mm. 
 What would have been the volume had the barometer 
 stood at 760 mm. ? 
 
 26. A volume of gas measured 467 cc. when the 
 barometer stood at 756 mm. What would it have 
 measured had the barometer stood at 760 mm. ? 
 
 27. A volume of air measured 137 cc. when the 
 barometer stood at 766 mm. What would it have 
 measured had the barometer stood at 757 mm. ? 
 
 28. If a certain mass of gas occupies 800 cc. at a 
 pressure of 76 cm., what would its volume be at 74 cm. 
 pressure ? 
 
CHANGES IN VOLUME 29 
 
 29. Into what space must 60 ft. 3 of air be com- 
 pressed that its expansive force may be made twelve 
 times as great ? 
 
 30. How strong would a compression tank have to 
 be if its capacity is 600 in. 3 and 5 ft. 3 of air at normal 
 pressure is forced into it ? 
 
 31. What will be the weight of a 1. of air under a 
 pressure of 300 in. of mercury ? 
 
 32. A rectangular diving bell 14 ft. high is sunk to 
 the bottom of a lake at a point where the water is 60 
 ft. deep. Find how high the water will rise in the bell. 
 
 II. Volume with temperature alone changing. 
 
 33. If 170 volumes of oxygen are measured at -f- 10 C., 
 what will the volume be when the temperature falls to 
 0C.? 
 
 34. If 10 cc. of a gas are measured at + 15 C., what 
 volume will the gas occupy at + 150 C. ? 
 
 35. If 100 cc. of hydrogen are measured at + 200 C., 
 how many cc. will the gas occupy at 200 C. ? 
 
 36. Calculate the temperature at which air possesses 
 a density equal to that of hydrogen at C. 
 
 37. A mass of gas at 0C. measures 2000 cc. Find 
 the volume at (a) - 7 C. ; (ft) + 10 C. ; (c) + 27 C. ; 
 (d) + 106C.; <V)-23 C. 
 
 38. An open vessel was heated until one-third of the 
 air it contained at C. was driven out ; how much 
 was it heated ? 
 
 39. How much must a 1. of air at + 10 C. be heated 
 in order to increase its volume two-thirds ? 
 
30 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 40. At what temperature would nitrogen have the 
 same density that hydrogen has at C. ? 
 
 41. What will be the volume of 250 cc. of hydrogen 
 measured at + 30 C. when cooled to - 10 C. ? " 
 
 42. What will be the volume at + 25 C. of 252 cc. of 
 oxygen measured at + 15 C. ? 
 
 43. If 170 volumes of oxygen are measured at 
 + 10C., what will the volume be if the temperature 
 falls to C. ? 
 
 44. When 600 cc. of oxygen at + 21 C. are cooled to 
 8 C., what is the new volume ? 
 
 45. A certain weight of air measures a 1. at C. ; 
 how much will the air expand on being heated to 
 + 100 C. ? 
 
 46. What is the temperature when 15 1. of a gas at 
 + 20 C. will occupy a volume of 18.6 1. ? 
 
 47. A flask holding 600 cc. of air at C. is heated to 
 H- 25 C. ; what volume of expanded air escapes ? Tem- 
 perature of escaped air is + 25 C. Neglect expansion 
 of flask. 
 
 48. A volume of gas measuring 500 cc. at C. was 
 expanded by heating to 600 cc. at constant atmospheric 
 pressure ; what temperature did the gas attain ? 
 
 49. A rubber balloon containing 400 cc. of oxygen 
 measured at 20 C. is subjected to a temperature of 
 -h 120 C. What is the increase in volume of the 
 balloon ? 
 
 50. At what temperature will 1 1. of chlorine weigh 
 the same as 1 1. of hydrogen ; 1 1. of N 2 O ; 1 1. of NH 3 ? 
 
 51. If 100 cc. of a gas at +10 C. is found to change 
 its volume to 110 cc., at what temperature is it then? 
 
CHANGES IN VOLUME 31 
 
 52. The temperature of a gas being raised from 
 - 15 C. to +10 C., it now measures 200 cc. Find the 
 original volume. 
 
 53. What volume will 1000 cc. of air at+13C. 
 occupy at +65 C. ? 
 
 54. If 300 cc. of gas are measured off at+28C., 
 what will the volume become at 14 C. ? 
 
 55. A 1. of gas is heated from + 14 C. to + 42C. 
 Find the new volume. 
 
 56. A 1. of air at + 39 C. is cooled to - 26 C. Find 
 the new volume. 
 
 57. What volume will 50 cc. of gas at + 10 C. occupy 
 
 at+24C.? 
 
 58. If 100 cc. of air at +12 C. are heated until they 
 occupy 145 cc., what is the new temperature ? 
 
 59. A volume of air, measuring 230 cc., was standing 
 in a 1. flask over water, the temperature of which was 
 + 26 C. The temperature was then raised to +60C. 
 How much water then remained in the flask? 
 
 60. I have a 1. flask full of hydrogen at + 15C. I 
 wish to expel half the gas. To what temperature must 
 it be heated ? 
 
 61. I have a 1. flask full of oxygen standing over 
 water at +90C. I wish 100 cc. of water to enter the 
 flask. What must be the temperature? 
 
 62. 3 1. of chlorine and 5 1. of hydrogen were mixed 
 and exposed to sunlight at a temperature of -f 15 C. 
 It was found, after the HC1 had been formed, that the 
 temperature had risen to + 40 C. What volume did 
 the gases then occupy? 
 
32 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 63. Below +500 C. sulphur has six atoms to the 
 molecule ; above 4-500 C. it has only two atoms to the 
 molecule. We have 300 cc. of sulphur gas at +450 C. 
 What will be the volume at + 800 C. ? 
 
 64. If 1000 cc. of gas are heated from C. to + 39 C., 
 what is the new volume ? 
 
 65. If 1000 cc. of gas are heated *from+39C. to 
 + 52 C., what is the new volume? 
 
 66. What volume will 20 ft. 3 of air at -7 C. have 
 
 at+7C.? 
 
 67. If the vapor density of a gas is 32 at the temper- 
 ature of -f-15C., at what temperature will it have a 
 vapor density of 28.16? 
 
 68. A quantity of gas was measured when its tem- 
 perature was + 12 C. At what temperature would its 
 volume be doubled? 
 
 69. An open vessel was heated to + 819 C. What 
 portion of the air that the vessel contained at C. re- 
 mained in it? 
 
 70. An open vessel was heated till l of the gas that 
 it contained at + 15 C. was driven out. What was the 
 temperature of the vessel? 
 
 71. A volume of air measured 475 cc. at + 27 C. 
 What would have been its volume at C. ? 
 
 72. A quantity of hydrogen measured 550 cc. at 
 4- 15 C. What would have been its volume had its 
 temperature been 10 C. ? 
 
 73. A given weight of air measured 256 cc. at 
 + 34 C. What would have been its volume had its 
 temperature been C. ? 
 
CHANGES IN VOLUME 33 
 
 74. A volume of nitrogen measured 3.5 1. at -f- 75 C. 
 What would have been its volume had its temperature 
 been + 15 C. ? 
 
 75. A volume of gas measured 50 cc. at -h 15 C. At 
 what temperature would its volume be 44 cc. ? 
 
 76. What volume will 400 1. of illuminating gas at 
 + 60 C. occupy at + 22 C., if there is no change of" 
 pressure ? 
 
 77. If 100 cc. of hydrogen are measured at 4- 100 C., 
 how many cc. will the gas occupy at 100 C. ? 
 
 78. What volume will 1000 cc. of hydrogen at C. 
 occupy at (a) + 15 C. ; (6) + 20 C. ; (e?) + 300 C. ? 
 
 79. A gas has its temperature raised from +19 C. to 
 + 50 C. ; at the latter temperature it measures 15 1. 
 What was the initial volume ? 
 
 80. A certain weight of air measures a 1. at C. 
 How much will the air expand on being heated to 
 + 100 C. ? 
 
 81. A volume of hydrogen measures 1500 cc. at C. 
 How many cc. will it measure at (#) + 15.5 C. ; (5) at 
 + 50 C. ; (<?) at +400 C. ; (d) at +600C.? At 
 what temperature will it measure exactly 1000 cc. ? 
 
 82. If 10 cc. of a gas are measured at + 18 C., what 
 volume will the gas occupy at + 150 C. ? 
 
 83. Calculate the temperature at which air possesses 
 a density equal to that of methane at C. 
 
 84. If the sp. gr. of air at -f 20 C. normal pressure 
 is 0.00118, what will be the weight of a 1. of air at 
 - 20 C. ? 
 
 85. A volume of air at C. measures 1 1. ; what will 
 be its volume at + 18 C. ? 
 
34 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 86. A volume of air at + 91 C. measures 1000 cc. 
 Reduce the volume to standard temperature. 
 
 87. An open vessel is heated from C. to + 546 C. 
 What portion of the air that it at first contained now 
 remains ? 
 
 88. Find the volume of the following at C. : (a) 
 "170 cc. at + 13 C. ; (5) 400 cc. at + 14 C. ; (<?) 771 
 cc. at +1 C. ; (d) 288 cc. at - 7 C. ; < 300 cc. 
 at + 200 C. 
 
 89. A 1. flask filled with air at 10 C. is heated to 
 + 70 C. What will be the volume of the air that 
 escapes if measured at C. ? 
 
 III. Volume with pressure and temperature both changed. 
 
 90. Given 800 cc. of nitrogen at -- 1 C. and 721 
 mm., what will be the volume at + 1 C. and ^ an at- 
 mosphere pressure ? 
 
 91. A certain quantity of nitrogen measures 155 cc. 
 at + 10 C. and under a pressure of 530 mm. What 
 will the volume become at + 18.7 C. and under a pres- 
 sure of 590 mm. ? 
 
 92. A volume of hydrogen at a temperature of + 15 
 C. measured 2.7 1. when the barometer stood at 752mm. 
 What would have been its volume had its temperature 
 been + 9 C. and the barometer stood at 762 mm.? 
 
 93. Given 18 cc. gas at + 16 C. and 772 mm., what 
 will be the volume at C. and 760 mm. ? 
 
 94. Given 14 cc. gas at + 11 C. and 900 mm., what 
 will be the volume at + 3 C. and 790 mm. ? 
 
 95. Given 2.7 1. at + 18 C. and 749 mm., what will 
 be the volume at C. and 760 mm. ? 
 
CHANGES IN VOLUME 35 
 
 96. Given 500 cc. of a gas at +163 C. and 8.72 
 mm., find its volume at + 77 C. and 10 mm. 
 
 97. A volume of air at standard temperature and 
 pressure is compressed to J its original volume, and the 
 temperature is then raised to + 25 C. What will now 
 be the pressure in atmospheres? 
 
 98. If 1500 cc. of nitrogen at +57 C. and 780 mm. 
 are cooled to + 27 C., the pressure being decreased to 
 740 mm., what is the new volume? 
 
 99. Given 500 cc. of hydrogen at + 25 C. and 760 
 mm. pressure, what will be the volume at -f 115 C. and 
 755mm.? 
 
 100. I fill a flask of 2 1. capacity with hydrogen when 
 the thermometer indicates + 25 C. and the barometer 
 762 mm. What is 'the volume at C. and 760 mm.? 
 
 101. I measure a volume of nitrous oxide at 755 mm. 
 and -f 17 C., and find 360 cc. What volume should it 
 occupy at 960 mm. and + 37 C. ? 
 
 102. Compute the. volume of carbon dioxide at 300 
 mm. and + 50 C. which is 25 1. at + 20 C. and 700 
 mm. 
 
 103. A certain mass of gas measures 11,000 gal. at 
 + 14 C. and 740 mm. pressure. To what volume will 
 it expand when the temperature reaches + 27 C. and 
 the pressure 620 mm. ? 
 
 104. If 100 1. of gas at + 30 C. and 731 mm. is 
 cooled to -f 25 C. while the pressure rises to 790 mm., 
 and is then measured again, what is its new volume ? 
 
 105. Given 500 1. of ammonia gas at + 135 C. and 
 752 mm., what will be its volume at + 100 C. and 760 
 mm. ? 
 
36 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 106. Given 730 cc. of nitrogen at + 25C. and 770 
 mm., what will be the volume of this mass of gas at 
 - 30 C. and 710 mm. ? 
 
 107. A quantity of illuminating gas measures 5 1. 
 and 25 cc. at + 17 C. and 760 mm. What will be its 
 volume at + 100 C. and 735 mm. ? 
 
 108. If 175 cc. of gas are measured at + 20 C. and 
 785 mm., what would be the volume of the same mass 
 of gas at C. and 760 mm. ? 
 
 109. Given 125 cc. of gas at +1C. and 750mm., 
 what will be the volume at C. and 650 mm. ? 
 
 110. Given 40 pt. of gas at + 10 C. and 740 mm., 
 what is the volume at 10 C. and 630 mm. ? 
 
 111. Given 1 ft. 3 of gas at 110 C. and 510 mm., 
 what is the volume at + 25 C. and 820 mm. ? 
 
 112. Given 1 gal. of gas at -f- 21 C. and 722 mm., 
 what is the volume at C. and 760 mm. ? 
 
 113. Given 300 1. of gas at - 100 C. and 310 mm., 
 what is the volume at C. and 760 mm.? 
 
 114. Given 22.16 m. 3 of gas at 0C. and 760 mm., 
 what is the volume at + 25 C. and 750 mm. ? 
 
 115. Given 0.18 1. of gas at C. and 760 mm., what 
 is the volume at 25 C. and 770 mm. ? 
 
 116. If a room measures 10 m. by 100 dm. by 1000 
 cm., what volume of air will escape from it if the tem- 
 perature changes from 11 C. to 15 C. ? What vol- 
 ume if the pressure changes from 760 mm. to 735 mm. ? 
 What volume if both temperature and pressure change 
 together ? 
 
 117. What mass of oxygen at + 10 C. and 750 mm. 
 would fill a globe of 16 1. capacity ? 
 
CHANGES IN VOLUME 37 
 
 118. If the volume of a mass of ammonia is 500 cc. 
 at + 40C. and under the pressure, of 60 mm., what 
 would it be under the pressure of 35 mm. at + 20 C. ? 
 
 119. If the volume of a mass of nitrogen is 50 cc. at 
 -f- 20 C. and under the pressure of 60 cm., what would 
 it be under the pressure of 900 mm. at + 100 C.? 
 
 120. If the volume of a mass of carbon dioxide is 
 2050 cc. at +200C. and under the pressure of 5 cm., 
 what would be the volume in 1. under the pressure of 
 400 mm. at + 50 C. ? 
 
 121. If the volume of a mass of steam is 50,000 cc. 
 at 200 C. and under the pressure of 1200 cm., what 
 would be the volume in 1. under the pressure of 20,000 
 mm. at + 250 C. ? 
 
 122. If 470 cc. of nitrous oxide at + 40 C. stand in 
 a tube over mercury, the level within the tube being 70 
 mm. above that without, and the barometric pressure 
 being 740 mm., what would be the volume of the gas at 
 + 15C., the barometric pressure being 765 mm. and 
 the level within the tube being 20 mm. below that 
 without ? 
 
 123. If 1 1. of carbon dioxide at -f 18 C. stand in a 
 tube over mercury, the level within the tube being 125 
 mm. below that without, and the barometric pressure 
 being 755 mm., what would be the volume of the gas at 
 H- 50 C., the barometric pressure being 74 cm. and the 
 level within the tube being 500 mm. above that with- 
 out? 
 
 124. If 300 cc. of air at +20C. stand in a tube 
 over mercury, the level within the tube being 20 cm. 
 above that without, and the barometric pressure being 
 750 mm., what would be the volume of the gas at 
 
38 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 -j-100C., the barometric pressure being 760 mm. and 
 the level within the tube being 70 cm. above that with- 
 out ? 
 
 125. If the pressure of 300 cc. of gas is 600 mm. at 
 + 5C., what pressure would be required to maintain 
 the volume at 350 cc. at + 100 C. ? 
 
 126. What volume will 30 g. of oxygen occupy at 
 4- 200 C. under the pressure of 80 cm. of mercury ? 
 
 127. At what temperature will J Kg. of sulphur 
 dioxide have a volume of 40 1. under 5 atmospheres 
 pressure ? 
 
 128. How many g. of nitrous oxide will occupy 900 
 cc. under the pressure of 2 atmospheres at 4- 50 C. ? 
 
 129. If 320 cc. of gas are measured at + 91 C. and 
 950 mm., what is the normal volume ? 
 
 130. If 542 cc. of air at +269C. and 900 mm. are 
 cooled to + 51 C., the pressure being decreased to 666 
 mm., what is the new volume ? 
 
 131. If 546 cc. of gas at + 17C. and 760 mm. are 
 cooled to 0C., the pressure being decreased to 600 
 mm., what is the new volume ? 
 
 132. A quantity of oxygen which measures 230 1. at 
 + 14 C. and 740 mm. will measure how much at C. 
 and 760 mm. ? 
 
 133. If 1234 cc. of normal gas are cooled to 52 C., 
 the pressure being decreased to 617 mm., what is the 
 new volume ? 
 
 134. The volume of a gas contained in a tube measures 
 86 cc., the mercury standing at a height of 34 mm. in 
 the tube. Barometric pressure is 742 mm. ; temperature 
 is + 23 C. What is the normal volume of the gas? 
 
CHANGES IN VOLUME 39 
 
 135. One 1. of oxygen at C. and 760 mm. pres- 
 sure weighs 1.4296 g. What will it weigh at the 
 same temperature with the barometer standing at 780 
 mm. ? 
 
 136. What will be the weight of 300 cc. of oxygen at 
 + 18 C. and with the barometer at 730 mm. ? 
 
 137. Under standard pressure at what temperature 
 will 1 1. of oxygen weigh 1 g. ? 
 
 138. What will be the volume of 200 g. of oxygen at 
 770 mm. pressure and + 27 C. ? 
 
 139. A volume of hydrogen measuring 500 cc. at 
 + 25 C. and 730 mm. was reduced in volume to 400 cc. 
 at C. What was the final pressure of the gas? 
 
 140. If 150 cc. of air are measured over water at 
 4- 18 C. and 746 mm. pressure, what will be the 
 volume at standard conditions? 
 
 141. Since 1 1. of oxygen at standard conditions 
 weighs 1.429 g., 440 cc. of this gas measured over 
 water at + 24 C. and 742 mm. pressure will contain 
 what weight of the dry gas ? 
 
 142. What increase in pressure is necessary to force 
 100 cc. of hydrogen at -f 46 C. and 740 mm. into a 
 vessel of 80 cc. capacity, when the temperature of this 
 vessel is constant at C. ? 
 
 143. Find volume under standard conditions of a mass 
 of oxygen occupying 75 cc. at + 40 C. and 750 mm. 
 pressure. 
 
 144. Chlorine occupies 20 1. at 720 mm. and -f 20 C. 
 Find volume when conditions change to 790 mm. and 
 + 30 C. 
 
40 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 145. A flask of air at standard conditions weighs 26 
 g. What capacity must it be, when filled with oxygen 
 at + 14 C. and 753 mm., to weigh 26.73 g. ? 
 
 146. The conditions in a vessel are +11 C. and 
 800 mm. What expansion would there be if the tem- 
 perature changed to -+-100C. and the pressure to 
 766 mm. ? 
 
 147. A cylinder contains air at + 5 C. and 4 atmos- 
 pheres pressure. Show that if the air is heated to 
 + 565 C. the cylinder must be able to stand a pressure 
 of over 12 atmospheres in order not to break. 
 
 148. A 1. of air is measured at 0C. and 760 mm. 
 What volume will it occupy at 740 mm. and + 15.5 C. ? 
 
 149. Given 375 cc. of oxygen at -fl7C. and 
 375mm., what will be the volume at standard condi- 
 tions ? 
 
 150. Given 3 1. hydrogen at + 15 C. and 752 mm., 
 what will be the volume at + 9 C. and 763 mm. ? 
 
 151. What is the sp. gr. of oxygen when the barom- 
 eter stands at 760 mm. and its temperature is C., if 
 its sp. gr. is 14.7648 when the barometer stands at 745 
 mm. and its temperature is + 17 C. ? 
 
 152. What decrease in pressure will be necessary to 
 raise a volume of gas measuring over water 400 cc., at 
 + 22.5 C. and 748 mm. pressure, to a volume of 440 cc. 
 under the same conditions? 
 
 153. What increase in atmospheric pressure will be 
 necessary to reduce 200 cc. of a gas, measured in a tube 
 over water at + 10 C. and 720 mm., to a volume of 
 100 cc. at + 20 C. in this same tube ? 
 
CHANGES IN VOLUME 41 
 
 154. If 98 1. of hydrogen are to be admitted into a 
 balloon at a temperature of + 20 C. and a pressure of 
 740 mm., what must be the capacity of the balloon? 
 
 155. Of what capacity is that vessel which contains 
 4 Kg. of oxygen at the temperature of +18 C. and a 
 pressure of 748.4 mm. ? 
 
 156. If 110.08 HI. of hydrogen at C. and 760 mm. 
 pressure are to be forced into a vessel of 11.2 1. 
 capacity, under what pressure will the hydrogen be at 
 this same temperature ? 
 
 157. What volume will 0.8 g. of hydrogen occupy 
 at + 100 C. under the pressure of 750 mm. of mer- 
 cury ? 
 
 158. What pressure will be exerted by 10 g. of car- 
 bon monoxide, the volume of which is 15 1. at +20 C. ? 
 (11. = 1.261 g.) 
 
 159. At what temperature will 20 g. of nitrous oxide 
 fill a space of 8000 cc. under twice the atmospheric 
 pressure? (1 1. =1.969 g.) 
 
 160. What is the weight of 51. of oxygen under the 
 pressure of 800 mm. of mercury at +40 C.? 
 
 161. What will be the pressure of 10 g. of marsh 
 gas, the volume of which is 15 1. at + 30 C. ? (11.= 
 0.716 g.) 
 
 162. If a certain volume of gas weighs 5 g. at + 50 C. 
 and 300 mm., what should a like volume of the same 
 gas weigh if measured at -+- 35 C. and 500 mm.? 
 
 163. A volume of chlorine measured at + 18 C. and 
 756 mm. weighs 3 g. If the same volume had been 
 found at +36 C. and 700 mm., what would it have 
 weighed? (1 1. Cl = 3.167 g.) 
 
42 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 164. Carbon dioxide at N.T.P. weighs 1.98 g. per 1. 
 What would a 1. of it weigh at + 30 C. and 800 mm. ? 
 
 165. What is the volume of 20 g. of ammonia at 
 + 12 C. and 730 mm. ? (11.= O.T6 g.) 
 
 166. If 146 1. of nitrogen at + 17 C. and 974 mm. 
 are heated to + 51 C., the pressure being decreased to 
 760 mm., what is the new volume ? 
 
 167. What is the mass of 270 cc. of nitrogen meas- 
 ured over water at 4-8 C. and 768 mm.? (1 1. = 
 1.25 g.) 
 
 168. A gas measured over water has a volume of 
 64.2 cc. at +18.6 C. and 742.5 mm. Find what the 
 volume would be at C. and 760 mm. 
 
 169. Given 400 cc. of oxygen at standard conditions, 
 what will -be the volume when measured over water at 
 + 20 C. and 755 mm. pressure? 
 
 170. Given 100 cc. of a gas measured over water at 
 4- 25 C. and 745 mm. pressure, what will be the vol- 
 ume when deprived of moisture ? 
 
 171. Given 1000 cc. of oxygen measured over water 
 at 4- 10 C. and 750 mm. pressure, what will be the 
 volume at 10 C. and 770 mm. pressure when de- 
 prived of moisture? 
 
 172. Given 500 cc. of a gas contained in a tube in- 
 verted over water, and measured at + 10 C. and 
 765 mm. pressure, what will be the volume under a 
 change in the atmospheric conditions to + 20 C. and 
 745 mm. pressure? 
 
 173. A vessel of 2000 cc. capacity held 5 g. of a 
 vapor at the standard conditions of temperature and 
 pressure. What weight of this vapor at + 10 C. and 
 
CHANGES IN VOLUME 43 
 
 750 mm. pressure can be held in this vessel, the capac- 
 ity considered constant? 
 
 174. Reduce the following to standard conditions : 
 (a) 150 cc. at 603 mm. and + 31 C ; (5) 400 cc. at 
 876 mm. and - 9 C. ; (c) 500 cc. at 371 mm. and 
 4-62.17 C. ; (d) 20 cc. at 700 mm. and -14 C. ; 
 0) 7 1. at 1376 mm. and +13 C. 
 
 175. A certain volume of gas is enclosed in a vessel 
 at 76 cm. pressure and 20 C. It is then heated to 
 -f- 40 C. What is the pressure on the sides of the 
 vessel measured in terms of the atmosphere? 
 
 176. If 1000 cc. of chlorine at + 46 C. are in a tube 
 over mercury which stands in the tube 39 mm. above 
 that without, the pressure outside being 750 mm., what 
 would be the volume of the gas under standard condi- 
 tions? 
 
 177. The air in a flexible rubber bag is found to oc- 
 cupy a volume of 1 ft. 3 at 30 in. pressure and +20 C. 
 If the bag is plunged to a depth of 170 ft. in water, the 
 temperature of which is + 10 C., what will be its vol- 
 ume? 
 
 178. A vessel full of air at C. is heated to + 80 C., 
 when 2 cc. of the air measured at C. are found to 
 have escaped. How much air was in the vessel before 
 heating ? 
 
 179. A 1. of chlorine at C. and 76 cm. pressure 
 weighs 3.167 g. If the pressure is decreased to 74 cm., 
 what must the temperature be that a 1. of gas may 
 weigh 2 g. ? 
 
 180. If a 1. of nitrogen at C. and 76 cm. pressure 
 weighs 1.25 g., how many 1. at +25 C. and 74 cm. 
 pressure will be required to weigh 8 g. ? 
 
44 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 181. Find the volume of 4450 cc. of carbon dioxide, 
 measured at standard conditions, at 890 mm. pressure 
 and + 27 C. 
 
 182. A 1. of hydrogen at 760 mm. pressure and C. 
 weighs 0.0899 g. What will 10 1. weigh at - 20 C. 
 and 750 mm. pressure? 
 
 183. At what temperature, when under a pressure of 
 75 cm., will 2 1. of gas measured at + 46 C. and 76 cm. 
 pressure measure 1.8 1. ? 
 
 184. A gas at C. and 760 mm. pressure measured 
 250 cc. What will it measure at -10 C. and 760 mm. 
 pressure ? 
 
 185. A volume of gas in a eudiometer measures 242 
 cc. The mercury in the tube stands 18 cm. above 
 that outside. Barometer at 740 mm. ; temperature, 
 + 18 C. Reduce to standard volume. 
 
 186. A volume of gas in a tube measures 72 cc. The 
 mercury in the tube stands at the same level as that on 
 the outside. Barometer 737mm.; temperature +17C. 
 What would be the volume under standard Conditions? 
 
 187. The volume of gas in a eudiometer measures 
 68 cc., the level of the mercury in the tube and trough 
 being the same. The barometer indicates an atmos- 
 pheric pressure of 739 mm. The temperature is + 20 C. 
 What would be the volume of the gas at C. and under 
 760 mm. pressure ? 
 
 188. The volume of gas contained in a tube measures 76 
 cc. The mercury in the tube stands at a height of 17 mm. 
 Barometer indicates a pressure of 752 mm. The tem- 
 perature is +9 C. Find volume at C. and 760 mm. 
 
 189. If the volume of a mass of gas is 500 cc. at 
 -f 30 C. and under the pressure of 100 mm., what would 
 
CHANGES IN VOLUME 45 
 
 it be under the standard conditions of atmospheric pres- 
 sure and the temperature C. ? 
 
 190. If the volume of a mass of hydrogen is 1000 cc. 
 at + 100 C. and under the pressure of 800 mm., what 
 would it be under standard conditions ? 
 
 191. If the volume of a mass of oxygen is 400 cc. at 
 + 50C. and under the pressure of 600mm., what 
 would it be under standard conditions ? 
 
 192. If the volume of a mass of air is 4 1. at + 70 C. 
 and under the pressure of 80cm., what would it be in 
 cc. under standard conditions? 
 
 193. If 500 cc. of chlorine at +60C. stand in a eu- 
 diometer over mercury, the level within the tube being 
 90 mm. above that without and the barometric pressure 
 being 750 mm., what would be the volume of the gas 
 under standard conditions ? 
 
 194. If 1250 cc. of nitrogen at + 37 C. stand in a 
 eudiometer over mercury, the level within the tube being 
 20 mm. below that without and the barometric pressure 
 being 747 mm., what would be the volume of the gas 
 under standard conditions? 
 
 195. If 780 cc. of air at +28 C. stand in a eudiome- 
 ter over mercury, the level within the tube being 40 mm. 
 above that without and the barometric pressure being 
 750mm., what would be the volume of the gas under 
 standard conditions ? 
 
 196. If J 1. of hydrogen at + 70 C. stands in a eudi- 
 ometer over mercury, the level within the tube being 
 50 mm. below that without and the barometric pres- 
 sure being 745 mm., what would be the volume of the 
 gas in cc. under standard conditions ? 
 
46 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 197. If the temperature of a certain volume of air is 
 increased from 10 C. to -f-30C., how much must the 
 pressure be increased to keep the volume constant ? 
 
 198. The barometer at C. stands at 750 mm. At 
 what height will it stand if the temperature rises to 
 + 39 C., the pressure remaining the same? 
 
 199. If a quantity of gas, measured at C. and 75 cm. 
 pressure, is subjected to a pressure of 775 mm., how much 
 must the temperature be increased that the volume may 
 remain the same ? 
 
 200. A sample of moist air, confined over water at 
 + 15 C. and 760 mm., occupies 15 cc. It is mixed with 
 20 cc. of hydrogen, the mixture is exploded, and suffers 
 a contraction of 9.5 cc. What would be the volume 
 of the oxygen it contained if measured dry at C. and 
 760 mm. ? 
 
 201. To how many atmospheres pressure must a 1. 
 of gas measured at 76 cm. pressure and 20 C. be 
 subjected to be condensed to J a 1. when the tempera- 
 ture is 4-40 C.? 
 
 202. A volume of gas which measures 2 1. at 742 mm. 
 was afterwards found to measure 2163 cc. What was 
 the height of the barometer at the time of the second 
 reading? 
 
 203. Some hydrogen under 900 mm. pressure and 
 -f 20 C. occupies 300 cc. What volume will it occupy 
 at +109 C. under 600mm. pressure? 
 
 204. Find the pressure on the gas in a tube when the 
 mercury inside and outside the tube are the same, and 
 the temperature is +25C. and the barometer stands 
 at 760 mm. 
 
CHANGES IN VOLUME 47 
 
 205. A 1. flask was filled with air at 10 C. and 
 750mm. pressure. If the barometer rises to 760mm., 
 to what temperature must the flask be raised to drive 
 out ^ the air that was in it when it was filled ? 
 
 206. The gas enclosed in a piston tube is compressed 
 to i| its original volume measured at 76 cm. pressure, 
 and the temperature is raised from +10 C. to +130 C. 
 What is the pressure on each cm. 2 of the piston? 
 
 207. When 1000 cc. of a gas were measured at -f 16 C. 
 and 750 mm., and the volume was increased to 1120 cc. 
 by warming, the final pressure read 740mm. What 
 was the final temperature of the gas? 
 
 208. What decrease in temperature will be necessary 
 to reduce 400 cc. of a gas at + 20C. and 765mm. to 
 a volume of 300 cc. at 750 mm. ? 
 
 209. If 1 g. of gunpowder yields, on explosion at C. 
 and 760 mm., 288 cc. of gases, what volume would be 
 occupied at + 2200 C., which is reached at the moment 
 of exploding? 
 
 210. What change in* temperature will be necessary 
 to bring a volume of gas, measuring 5600 cc. at + 10 
 C. and 745 mm. pressure, to a volume of 600 cc. at this 
 same pressure? 
 
CHAPTER V 
 
 Volumes of Gases from Weights Specific Gravity and 
 Vapor Density 
 
 1. Calculate the density, weight of 11., and sp. gr. 
 of the following gases : 
 
 C 2 H 2 , CO, C 2 H 4 , CH 4 , C 3 H 8 , 
 
 NH 3 , COS, HBr, NO, C 3 H 6 , 
 
 AsH 3 , COC1 2 , HC1, N 2 , SO 2 , 
 
 Br 2 , C1 2 , HF, N 2 O, H 2 O. 
 
 C4H 10 , C 2 N 2 , HI, 2 , 
 
 CO 2 , C 2 H 6 , H 2 S, PH 3 , 
 
 2. Find the weight of 10 1. of NO. What volume 
 will 5 g. of the gas occupy ? 
 
 3. Find the weight of the following volumes of dry 
 air at standard conditions : (a) 20 cc. ; (5) 300 cc. ; (c) 
 731.; (d)30mmA 
 
 4. Determine the weight, at C. and 760 mm., of 
 1 1. of each of the following gases, on the assumption 
 that they can exist in the gaseous condition at the 
 standard temperature and pressure : 
 
 Water, Trihydrogen phosphide, 
 
 Hydrogen chloride, Alcohol, 
 
 Ammonium chloride, Nitrogen monoxide, 
 
 Carbon dioxide, Nitrogen tetroxide, 
 
 Carbon disulphide, Mercuric chloride. 
 
 48 
 
VOLUMES, SPECIFIC GRAVITY, VAPOR DENSITY 49 
 
 5. What is the weight of 1500 cc. of a gas at the 
 standard pressure of 760 mm. and temperature of zero, 
 if its sp. gr. referred to hydrogen is 14? 
 
 6. Under a pressure of 745 mm., 1500 cc. of chlorine 
 weigh 4.67 g. What is the weight of 1 1. under 
 standard pressure ? 
 
 7. The formula for ethane is C 2 H 6 . Calculate the 
 sp. gr. of its vapor (a) compared with hydrogen ; (5) 
 compared with air. 
 
 8. Two 1. of hydrogen sulphide weigh 3.0442 g. ; 
 what is its sp. gr. referred to air ? 
 
 9. The molecular weight of bromine is 160 ; what 
 is the sp. gr. ? 
 
 10. What will be the volume of phosphorus vapor 
 obtained from 3 g. of solid phosphorus at + 420 C. ? 
 
 11. The density of carbon monoxide is 14 ; what is 
 the weight of 1 1. ? 
 
 12. How many 1. of hydrogen in 2.7 g.? 
 
 13. How many 1. of chlorine in 7.3 g.? How many 
 cc.? 
 
 14. What volume of HC1 in 50 g. ? 
 
 15. If 2 1. of chlorine weigh 6.3 g., find the density 
 of chlorine. 
 
 16. If 5 1. of CO 2 weigh 9.9 g., what is its density? 
 
 17. If 3 1. of mercury vapor weigh 26.9 g., compute 
 the vapor density of mercury. 
 
 18. Calculate the weight of 1 1. of each of the following 
 gases : (#) chlorine ; (ft) nitrogen ; (c) sulphur dioxide ; 
 (d) nitrous oxide ; (0) nitric oxide ; (/) ethane ; (#) 
 butane ; Qi) hydrogen chloride ; (i) carbon monoxide ; 
 (/) carbon dioxide ; (&) marsh gas ; (7) phosphine. 
 
50 PROGRESSIVE PROBLEMS Itf CHEMISTRY 
 
 19. What do 100 1. of nitrogen weigh? 
 
 20. Nitric oxide is 15 times as heavy as hydrogen ; 
 how many times is it heavier than air ? 
 
 21. Calculate the density (referred to air) of propane. 
 
 22. Calculate the density (referred to air) of sulphur 
 dioxide. 
 
 23. The vapor of silicon chloride is 5.936 times as 
 heavy as air. Find its density compared with hydrogen. 
 
 24. A vessel holding 30.8 g. of carbon dioxide at 
 + 10C. and 740 mm. pressure is to be brought to a 
 temperature of -f 50 C. and a pressure of 750 mm. 
 What weight and volume of carbon dioxide will be 
 lost? 
 
 25. What is the weight of 6.594 1. of oxygen at 
 + 40 C. and 740 mm. pressure ? 
 
 26. The relative density of carbon dioxide is 21.83; 
 what is the relative density of this gas upon the oxygen 
 standard ? 
 
 27. Find the density (air = 1) of the following : car- 
 bon monoxide ; carbon disulphide ; sulphur dioxide ; 
 boron trifluoride ; phosphorus pentafluoride. 
 
 28. Find the volume at standard conditions of 1 g. 
 H; 16 g. O; 14 g. N; 35.5 g. Cl ; 80 g. Br vapor; 
 9 g. steam; 18.25 g. HC1; 22 g. CO 2 ; 8 g. CH 4 ; 32 
 g. S0 2 ; 14 g. CO. *" 
 
 29. What weight of arsenic is contained in a 1. of 
 cacodyl oxide vapor, [(CH 3 ) 2 As] 2 O, measured at 
 + 500C.? 
 
 30. What is the volume of 3.0571 g. of a gas, if its 
 sp. gr. referred to air is 0.591? 
 
VOLUMES, SPECIFIC GRAVITY, VAPOR DENSITY 51 
 
 31. A hall is of such dimensions that it contains 
 50T.0912 Kg. of air at C. and 760 mm. What is the 
 capacity of the hall measured in m. 3 ? 
 
 32. Determine the mass of 750 cc. of nitrogen meas- 
 ured over water at + 20 C. and 780 mm. 
 
 33. If 545 cc. of nitrogen are measured over water at 
 + 22 C. and 748 mm. pressure, what weight will they 
 contain of the dry gas ? 
 
 34. What volume will 2.2 g. of oxygen at +20C. 
 and 770 mm. pressure occupy when transferred to a 
 vessel inverted over water ? 
 
 35. What volume will 1 g. of hydrogen measured at 
 standard conditions occupy when transferred to a vessel 
 over water at C. and 760 mm. pressure ? 
 
 36. What volume will 310 g. of carbon dioxide oc- 
 cupy when contained in a vessel over water at -f-20C. 
 and 742.4 mm. pressure ? 
 
 37. What volume will 1 g. of oxygen occupy over 
 water at -f- 30 C. and 756.5 mm. pressure ? 
 
 38. At what temperature will 8 g. of oxygen under 
 a pressure of 760 mm. occupy a volume of 11.1 1. at 
 this same pressure ? 
 
 39. Find the mass of 250 1. of chlorine at -7C. 
 and 886 mm. 
 
 40. The sp. gr. of oxygen under standard conditions 
 is 1.1; what is the sp. gr. when the barometer stands 
 at 745 mm.? 
 
 41. The sp. gr. of oxygen referred to hydrogen is 16 
 at 0C.; what is its sp. gr. when its temperature is 
 
 + 27C.? 
 
52 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 42. If the sp. gr. of a gas is 22 at C., what will be 
 itssp. gr. at + 81.9C.? 
 
 43. Calculate the weight of the following gases at 
 standard pressure and temperature : 2 1. of hydro- 
 chloric acid gas ; 1500 cc. of hydrogen sulphide ; 250 
 cc. of chlorine ; 5 1. of ethane (C 2 H 6 ). 
 
 44. The density of a substance referred to air is 3.2. 
 What is the density referred to hydrogen ? What will 
 be the volume occupied by 10 g. of the substance at 
 + 20C. and 752 mm.? 
 
 45. How many g. do 10 1. of hydrogen phosphide 
 weigh ? 
 
 46. A 1. of hydrogen under standard conditions 
 weighs 0.09 g. What is the weight of a 1. of ozone 
 under the same conditions? 
 
 47. A gas has the formula C 3 H 8 . Is it lighter or 
 heavier than air ? Find the sp. gr. 
 
 48. Calculate the sp. gr. of cyanogen and the weight 
 of 31. 
 
 49. Determine the mass of 7.3 1. marsh gas, 8 1. of 
 ethylene, and 16 g. choke damp, measured at 760 mm. 
 and C. 
 
 50. Find the weight at + 182 C. and 770 mm. oc- 
 cupied by 50 1. of (a) HF, (5) HI, (e) HC1. 
 
 51. What mass of nitrogen will measure 1000 cc. at 
 + 15C. and 765 mm.? 
 
 52. Find under standard conditions the weight of 1 1. 
 of CO, CO 2 , and CH 4 . 
 
 53. Find the mass of 5.6 1. of CO. 
 
 54. What space will 125 g. of iodine vapor occupy 
 at + 1900 C. and 794 mm. ? 
 
VOLUMES, SPECIFIC GRAVITY, VAPOR DENSITY 53 
 
 55. What is the volume of 20 g. of carbon dioxide 
 at the standard temperature and pressure? 
 
 56. What is the volume of 82.88 g. of the vapor of 
 ethyl ether at the temperature of + 147 C. and under 
 a pressure of 740 mm. ? 
 
 57. What weight of carbon does 1 1. of CO 2 contain ; 
 11. CO? 
 
 58. What is the weight of 5 1. of ethyl alcohol vapor 
 having a temperature of + 127 C. and under a pres- 
 sure of 750 mm. ? 
 
 59. What is the volume of a Kg. of carbon monoxide 
 at C. and 760 mm. ? 
 
 60. What is the volume of 225 g. of hydrogen sul- 
 phide at C. and 760 mm. ? 
 
 61. Calculate the volume, at the standard tempera- 
 ture and pressure, of a Kg. of the following gases : 
 carbon monoxide ; ethylene ; hydrogen sulphide ; oxy- 
 sulphide of carbon ; methyl hydride ; bromine ; water. 
 
 62. What volume will 49.63 g. of chlorine occupy at 
 standard conditions? 
 
 63. What is the volume occupied by 8.8 g. of carbon 
 dioxide at +12 C. and 752 mm. pressure? 
 
 64. Find the volume of 10 g. N 2 O ; 13 g. NO ; 7 g. 
 N 2 3 ; 6g. N 2 4 . 
 
 65. What volume of hydrogen is contained in 6 cc. 
 of NH 3 ? 
 
 66. Find the weight of 500 cc. of H ; 250 cc. of Cl; 
 700 cc. of CH 4 ; 130 cc. of PH 3 . 
 
 67. Find the volume at +41 C. and 785 mm. oc- 
 cupied by O) 66 g. CO 2 ; (6) 96 g. AsH 3 . 
 
54 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 68. The weight of 1 1. of aqueous vapor at C. and 
 760 mm. is 0.8045 g; what is its relative density? 
 
 69. Calculate the relative density of mercury vapor, 
 1 1. of which at standard conditions weighs 8.87 g. 
 
 70. A 1. of NH 3 weighs 0.762 g. at C. and 
 760 mm. Find (a) its vapor density ; (&) its sp. gr. 
 
 71. Find the volume at +41 C. and 78.5 mm. oc- 
 cupied by (a) 66 g. CO 2 ; (6) 96 g. stibine. 
 
 72. What is the weight of 573 cc. of air at + 30 C. 
 and 769 mm. ? 
 
 73. What is the weight of a m. 3 of hydrogen at the 
 standard temperature and twice the standard pressure? 
 
 74. What weight of hydrogen and of bromine in 
 1 1. HBr at + 60 C. and 760 mm. ? 
 
 75. How many times heavier than a 1. of hydrogen is 
 (a) one of air ; (5) one of oxygen ; (c) one of chlorine ; 
 (cT) one of nitrogen ? 
 
 76. Find the weight of 300 cc. NH 3 . 
 
 77. How many g. in 3000 cc. of H 2 S, measured at 
 + 16C. and 780 mm.? 
 
 78. Determine the mass of 34 1. of (a) NH 3 ; 
 (5)S0 2 ; (OSiF 4 ; (<OC a H a . 
 
 79. Find the volume at -f- 10 C. and 761 mm. oc- 
 cupied by (a) 3 g. H 2 S; (6) 13 g. PH 3 ; (*) 2 g. 
 SbH 3 . 
 
 80. The weight of 2.3 1. of oxygen at C. and 
 760 mm. is 3.2885 g. Find the sp. gr. referred to 
 air. 
 
 81. Three 1. of marsh gas weigh 2.15 g. What is 
 its sp. gr., hydrogen being the standard? 
 
VOLUMES, SPECIFIC GRAVITY, VAPOR DENSITY 55 
 
 82. At 760 mm. pressure, what is the weight of 1 1. 
 of acetylene at C. ; of hydrogen sulphide at C. ; 
 of steam at +150 C. ; of water at +4 C. ; of sul- 
 phuric acid, sp. gr. 1.84; of sulphur at -f- 500 C.; of 
 bromine at + 4 C. ; of bromine at -f- 400 C. ; of iodine 
 at + 500 C. ; of iodine at + 1500 C, ? 
 
 83. What volume is occupied by 177.5 g. of chlorine? 
 
 84. Find the number of 1. occupied by 64 g. of sul- 
 phur dioxide ; occupied by 32 g. of oxygen ; occupied 
 by 2 g. of hydrogen ; occupied by 16 g. of methane. 
 
CHAPTER VI 
 
 Weights from Equations 
 
 1. How much KC1O 3 must be decomposed to yield 
 20 g. of oxygen? What weight of KC1 will be left? 
 
 2. How many g. of CO 2 will be produced by burn- 
 ing 100 g. of carbon in oxygen? 
 
 3. How many g. of hydrogen will result from 
 placing 46 g. of sodium on water ? 
 
 4. How many g. of acetylene gas will be generated 
 by 750 g. of pure calcium carbide ? 
 
 5. How many Ib. of water would be needed to 
 slake 15 Ib. of CaO? 
 
 6. In the changing of 500 Ib. of Ca(OH) 2 in mortar 
 to CaCO 3 , how many Ib. of water are produced and 
 how many 1. of CO 2 are needed? 
 
 7. How much plaster of Paris results from heating 
 100 Kg. of gypsum? 
 
 8. How many Ib. of CaO and how many m. 3 of 
 CO 2 would be formed by heating 5 tons of limestone? 
 
 9. From 30 tons of sodium nitrate, how much nitric 
 acid (80% HNO 3 ) can be produced? How much sul- 
 phuric acid is necessary to make it ? 
 
 10. How much CO will result on heating 70 g. 
 of H 2 C 2 O 4 with concentrated H 2 SO 4 ? 
 
 56 
 
WEIGHTS FROM EQUATIONS 57 
 
 11. If 100 g. H 2 C 2 O 4 are heated with H 2 SO 4 and the 
 gases are passed through a solution of NaOH, what 
 volume of CO and what weight of Na 2 CO 3 will result ? 
 
 12. What weight of HC1 cau be made from 50 g. of 
 NaCl? 
 
 13. What weight of arsenic would be obtained by 
 reducing 157 g. of arsenic trioxide with charcoal ? 
 
 14. If a candle consists of 85 % of carbon and 15 % of 
 hydrogen, what weights of carbon dioxide and water 
 will be formed when 25 g. of the candle burn ? 
 
 15. To what weight of nitrous acid do 100 g. of 
 nitrous anhydride correspond ? 
 
 16. How much nitrogen peroxide is obtainable from 
 200 g. of nitric acid? 
 
 17. What weight of copper nitrate is obtainable from 
 50 g. of nitric acid and copper? 
 
 18. How much nitrogen peroxide can be made from 
 100 g. of nitric oxide ? 
 
 19. How much hydrocyanic acid is obtainable from 
 70 g. of potassium cyanide ? 
 
 20. How much cyanogen is obtainable from 200 g. -of 
 mercuric cyanide ? 
 
 21. What weight of carbon dioxide will 300 g. of 
 calcium carbonate yield on treatment with an acid? 
 
 22. What weight of NaOH and HC1 will be needed 
 to produce 75 g. of NaCl? 
 
 23. If 100 Kg. of "fool's gold" are heated (a) in 
 a tube, (5) in the air, what are the weights of the sub- 
 stances produced in each case ? 
 
 24. What weight of Na 2 CO 3 will result from heating 
 500 g. of sodium dicarbonate ? 
 
58 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 25. What weight of washing soda would be needed 
 to furnish 125 g. of anhydrous Na 2 CO 3 ? 
 
 26. What weight of nitric acid will be produced by 
 heating 75 g. of Chili saltpeter with an excess of con- 
 centrated sulphuric acid ? 
 
 27. What weight of sulphuric acid and sodium ni- 
 trate should be taken in order to obtain 215 g. of nitric 
 acid? 
 
 28. If 78 g. of copper nitrate is decomposed by con- 
 centrated sulphuric acid, what weight of nitric acid and 
 what weight of copper sulphate will be formed? 
 
 29. If copper and nitric acid react, what weight of 
 metallic copper should be taken, if one Kg. of copper 
 nitrate is to be formed? 
 
 30. What weight of nitrogen tetroxide (N 2 O 4 ) will 
 result when 3300 cc. of nitric oxide (NO) is brought into 
 contact with an excess of oxygen ? 
 
 31. What weight of N 2 O will be formed by heating 
 50 g. of NH 4 NO 3 ? How many g. of water will be 
 formed? 
 
 32. What weight of NH 4 NO 3 will be taken to yield 
 upon heating 1 1. of N 2 O ? 
 
 33. What weight of NH 3 will result upon decompos- 
 ing 50 g. of NH 4 C1 with slaked lime? 
 
 34. What weight of potassium and what weight of 
 chlorine are contained in 17 g. of potassium chlorate? 
 
 35. How much potassium chloride would be formed 
 by heating 35 g. of potassium chlorate ? 
 
 36. How much BaO 2 must be heated in order to ob- 
 tain 14 g. of oxygen? 
 
WEIGHTS FROM EQUATIONS 59 
 
 37. If potassium chlorate costs 80 cts. per Kg., what 
 will be the cost of enough to make 500 g. of oxygen ? 
 
 38. What weight of sodium will be necessary to de- 
 compose 15 g. of water? What weight of hydrogen 
 will be formed ? 
 
 39. What weight of sodium would be needed to pro- 
 duce, by the decomposition of water, 1 1. of hydro- 
 gen? 
 
 40. What weight of oxygen can be obtained by heat- 
 ing 18 g. of mercuric oxide ? 
 
 41. How much mercuric oxide must be heated in 
 order to obtain 2 g. of oxygen? 
 
 42. With what weight of mercury will 9 g. of oxy- 
 gen unite to form mercuric oxide? 
 
 43. To obtain 15 g. of iodine, how much manganese 
 dioxide, potassium iodide, and sulphuric acid will be re- 
 quired? 
 
 44. What weight of hydrofluoric acid would be 
 evolved by treating 36 g. of calcium fluoride with sul- 
 phuric acid? 
 
 45. How much common salt will be needed to yield 
 10 g. of chlorine on treatment with manganese dioxide 
 and sulphuric acid? 
 
 46. What weight of zinc sulphate will be formed upon 
 treating 13 g. of zinc with sulphuric acid? 
 
 47. How much manganese dioxide will be required 
 to liberate 13 g. of chlorine from hydrochloric acid? 
 
 48. What weight of chlorine will result from the 
 electrolysis of a solution containing 65 g. of potassium 
 chloride ? 
 
60 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 49. An ore contains 62.38% of arsenopyrite (FeAsS). 
 What weight of white arsenic could be obtained by 
 heating 500 Ib. of the ore ? 
 
 50. What weights of mercury and sulphur dioxide 
 could be obtained from 1 ton of an ore carrying 53.78% 
 of cinnabar? 
 
 51. What weight of aluminum oxide is contained in 
 100 Ib. of potassium alum? 
 
 52. What weight of aluminum hydroxide will be pro- 
 duced when a solution containing 35 g. of potassium alum 
 is precipitated with ammonium hydroxide? 
 
 53. An ore contains 23.46 % of stibnite, Sb 2 S 3 ; what 
 is the / of antimony in the ore ? 
 
 54. How many Ib. of calcium carbide will be neces- 
 sary to produce 1300 g. of acetylene? 
 
 55. How many Ib. of zinc may be obtained from a 
 ton of an ore containing 17.3 % of zinc carbonate? 
 
 56. What weight of silicon tetrafluoride could be ob- 
 tained by treating 430 g. of silica with hydrofluoric 
 acid? 
 
 57. If 275 g. of silica is fused with an excess of po- 
 tassium carbonate, what weight of potassium silicate 
 (K 2 SiO 3 ) will result? 
 
 58. From 1500 Ib. of salt how many Kg. of sodium 
 carbonate can be obtained by the Leblanc process ? How 
 much charcoal and how much limestone will be re- 
 quired ? 
 
 59. What weight of calcium sulphide will be pro- 
 duced in the manufacture of 1 ton of dry sodium car- 
 bonate by the Leblanc process? 
 
WEIGHTS FROM EQUATIONS 61 
 
 60. What weights of salt, ammonia, and carbon dioxide 
 will be necessary to produce 1 ton of NaHCO 3 by the 
 Solvay process? 
 
 61. In a case of poisoning, 11.73 g. of arsenic tri- 
 sulphide were found ; to how much arsenic trioxide does 
 this correspond? 
 
 As 2 S 3 + 9 O = As 2 O 3 + 3 SO 2 . 
 
 62. If I wish to make ferrous sulphide, how many g. 
 of sulphur should I mix with 56 g. of iron filings, and 
 how much ferrous sulphide should result ? 
 
 63. How much hydrogen and how much zinc chloride 
 should result from treating 25 g. of zinc with a sufficient 
 quantity of hydrogen chloride ? 
 
 64. What weight of oxygen is needed to burn a dia- 
 mond which weighs half a gr. ? What will the CO 2 
 formed weigh ? 
 
 65. How much sulphuric acid will neutralize 50 Ib. 
 of sodium hydroxide ? 
 
 66. How much lead is needed to form 2 Kg. of lead 
 nitrate ? 
 
 67. How many g. of HNO 3 will 140 g. of NH 4 NO 3 
 give ? 
 
 68. How many g. of iodine in 166 g. of KI ? 
 
 69. How many tons of pyrite containing 39.2% 
 of available sulphur are needed to make 4000 tons of 
 sulphuric acid of sp. gr. 1.730 containing 80% pure 
 H 2 SO 4 and allowing for no losses ? 
 
 70. What weight of iron rust may be obtained with 
 a supply of 10 g. of oxygen ? 
 
 71. How much MnO 2 is needed to make 125 g. of 
 chlorine from HC1 ? 
 
62 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 72. What weight of ammonium chloride, when acted 
 upon by calcium hydroxide, is required to produce 17 
 g. of ammonia, and what weight of calcium chloride is 
 formed at the same time ? 
 
 73. How much " laughing gas " may be made from 
 80 g. of NH 4 N0 3 ? 
 
 74. How much KI is needed to prepare 63.5 g. of 
 iodine ? 
 
 75. How much K 2 CO 3 and Ca(OH) 2 will give a Kg. 
 of KOH ? 
 
 76. Find the weight of Hg and O from decomposing 
 10 g. of HgO. 
 
 77. How many g. of NH 4 NO 3 must be used to pro- 
 duce 20 g. of N 2 O ? 
 
 78. How much phosphorus is there in 1 ton (2000 
 Ib.) of bone ash? 
 
 79. What weight of zinc will be required to decom- 
 pose 10,000 Ib. of sulphuric acid ? 
 
 80. What weight of zinc and of sulphuric acid is 
 necessary to prepare 50,000 1. of hydrogen at + 31 C. 
 and 758 mm. pressure ? 
 
 81. One Kg. of phosphorus is converted into phos- 
 phoric anhydride. What weight of phosphoric acid 
 will this yield ? 
 
 82. Find the g. of each component in 76 g. of HNO 3 . 
 How many g. of nitric oxide can be set free by the 
 action of 252 g. of HNO 8 on copper ? 
 
 83. What weight of sulphur is contained in 100 g. of 
 pyrite ? 
 
 84. How much silver is contained in 100 g. of an 
 impure specimen of silver chloride which is 33 % sand ? 
 
WEIGHTS FROM EQUATIONS 63 
 
 85. What weight of oil of vitriol of 97 % can be 
 made from 1000 Kg. of sulphur ? 
 
 86. What weight of oxygen is necessary to burn the 
 sulphur derived from the decomposition of 1 g. of 
 sulphurous anhydride, and what is the weight of the 
 product ? 
 
 87. Calculate the weight of tin and hydrochloric acid 
 necessary to produce 16 g. of hydrogen. 
 
 88. How much sodium carbonate and calcium hy- 
 droxide are needed to make a Kg. of sodium hydroxide ? 
 
 89. Find the weight of each of the products formed 
 by the complete combustion of 52 g. of turpentine. 
 
 90. A certain weight of MnO 2 is heated till decom- 
 posed ; if the residue weighs 149 g., what weight of 
 oxygen was evolved ? 
 
 91. How many g. of CaCO 3 must be used to prepare 
 22 g. of carbon dioxide by the action of HC1 ? 
 
 92. If 2 g. of silver are dissolved in nitric acid 
 and half a g. of pure, dry sodium chloride is added, 
 what percentage of the silver remains in solution ? 
 
 93. How much potassium, by its action upon water, 
 is required to furnish 2J g. of hydrogen ? 
 
 94. Find the number of g. of HC1 that can be set 
 free by the complete action of 10 g. of H 2 SO 4 on 
 common salt. 
 
 95. The ammonia obtained from 20 Kg. of ammo- 
 nium chloride is united with sulphuric acid to form the 
 neutral salt. What is the weight of the product ? 
 
 96. How many Ib. of limestone are needed to pro- 
 duce 1 ton of quicklime ? 
 
64 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 97. To obtain 15 g. of bromine, how much MnO 2 , 
 KBr, and H 2 SO 4 should be used ? 
 
 98. What weight of a gas mixture known as " water 
 gas" can be obtained from 24 Ib. of carbon and the 
 necessary steam ? 
 
 99. What is the weight of BaO in 1.5 g. of barium 
 carbonate? 
 
 100. How many g. of silver will 5 g. of sodium bro- 
 mide precipitate from a solution of silver in nitric acid ? 
 
 101. If a solution containing 50 g. of lead nitrate 
 is precipitated by hydrogen sulphide, what will be the 
 weight of the precipitate ? 
 
 102. If a solution containing 50 g. of copper sulphate 
 is precipitated by hydrogen sulphide, what will be the 
 weight of the precipitate ? 
 
 103. How much sulphuric acid could be produced 
 from the sulphur dioxide arising from the combustion 
 of 1 ton of sulphur? . 
 
 104. How much sulphuric acid could be produced 
 from the sulphur dioxide arising from the combustion 
 of 1 ton of pure pyrite ? 
 
 105. If 100 cc. of a solution of barium chloride that 
 contains 20 g. of the salt in 1 1. is precipitated by sul- 
 phuric acid, what weight of BaSO 4 will be formed ? 
 
 106. How much potassium chlorate can be made 
 from 150 g. of potassium hydroxide according to the 
 following reaction : 
 
 6 KOH + 3 C1 2 = KC1O 3 + 5 KC1 + 3 H 2 O ? 
 
 107. How much AgNO 3 can be obtained from 15 g. 
 of Ag, and how much H 2 O and how many g. of NO 
 will be formed ? 
 
WEIGHTS FROM EQUATIONS 65 
 
 108. AsH 3 is decomposed into its elements. How 
 many mg. of each element from 550 cc. of AsH 3 ? 
 
 109. How much hydrogen potassium carbonate is 
 required to give 1.98 g. of carbon dioxide ? 
 
 110. How much manganese dioxide is required to 
 charge a wedge-shaped gas bag, 1 m. high and wide 
 and | m. basal thickness, with oxygen at +15 C.? 
 
 111. One g. of Ca(OCl) 2 is boiled with water and 
 CuO. What weight of oxygen is evolved ? 
 
 112. A solution contains 30 g. of silver nitrate. How 
 much common salt is required to decompose the silver 
 nitrate, and how much silver chloride is produced ? 
 
 113. If 1 Kg. of HNO 3 is needed, what weights of 
 materials are required to make it ? 
 
 114. CHKO 2 (potassium formate) + KOH = K 2 CO 3 
 + H 2 . In the above equation, if 1 Kg. of CHKO 2 is 
 used, find the weight of gas evolved. 
 
 115. How much hydrochloric acid can be obtained by 
 treating 1 Kg. of common salt with sulphuric acid? 
 How much sulphuric acid will be needed ? 
 
 116. A piece of potassium is thrown on water; the 
 KOH will just neutralize 50 cc. of a solution of 
 H 2 SO 4 containing 98 g. Find the weight of potassium 
 used. 
 
 117. If 2 g. of Ag 2 O are thrown into hydrogen perox- 
 ide, what weight of gas is evolved ? 
 
 118. If 200 Ib. of nitre and enough H 2 SO 4 are heated 
 together, what weight of HNO 3 is given off? 
 
 119. What weight of CO 2 is needed to convert 
 50 tons of "soda" crystals into dicarbonate of 
 soda? 
 
66 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 120. A diamond weighing 0.3 g. is burned in a jar 
 of oxygen. How much CaCO 3 would be formed by 
 shaking the contents of flask after combustion with lime- 
 water ? 
 
 121. A certain amount of H 2 SO 4 requires 10 g. of 
 BaCl 2 to precipitate it completely. Find the weight of 
 acid used. 
 
 122. How much water must be added to 100 g. of 
 P 2 O 6 to form orthophosphoric acid ? 
 
 123. A copper coin liberates from sulphuric acid 
 22 g. of SO 2 . Find the weight of the coin. 
 
 124. How much carbon heated in the air will give 
 14 g. of C0 2 ? 
 
 125. 13 g. C 6 H 6 is burned in air. Find the weight of 
 oxygen used and the weight of the gaseous products. 
 
 126. What weight of calcium carbide (3 C + CaO = 
 CaC 2 + CO) will 600 Ib. of lime make ? How much 
 carbon is needed ? 
 
 127. Hydrogen is passed over 2.48 g. of heated CuO 
 and the weight is 2.24 g. The water formed weighs 
 0.27 g. Calculate the weight of H and O. 
 
 128. How much KC1 can be obtained from 200 g. 
 KC1O 3 containing 12% of impurities? Find weight of 
 oxygen given off. 
 
 129. Iron dissolved in hydrochloric acid gives 66 cc. 
 of hydrogen. Find the weight of iron used. 
 
 130. Water is decomposed and the oxygen is burned 
 with pure carbon, giving 44 g. of CO 2 . How much 
 water was used? 
 
 131. One Kg. of NaNO 3 is treated with oil of vitriol. 
 Find the weight of aqua fortis produced. 
 
WEIGHTS FROM EQUATIONS 67 
 
 132. How much fluorspar will be needed to unite 
 with 100 g. of H 2 SO 4 ? 
 
 133. If 10 g. of carbon are heated with 67 g. of CO 2 , 
 what weight (a) of CO is formed; (6) of residue, if 
 any? 
 
 134. v To get 76 Kg. of oxygen, how much air is 
 needed? 
 
 135. In 300 Ib. of bone ash are contained : (a) how 
 many Ib. of oxygen ; (&) how much calcium ? 
 
 136. If the bones of a man weigh 26 Ib. and contain 
 60 % Ca 3 (PO 4 ) 2 , find (a) the weight of phosphorus; 
 (5) the value of the skeleton to make phosphorus pent- 
 oxide at |3 a pound. 
 
 137. If 4 Kg. of Na 2 CO 3 are heated with carbon, 
 what is the weight of sodium produced and of carbon 
 used? 
 
 138. How many g. of oxygen and of hydrogen can 
 be obtained by the decomposition of 27 g. of water? 
 
 139. How many g. of oxygen can be obtained by the 
 decomposition of 100 g. of mercuric oxide? 
 
 140. If 3 g. of urea are warmed with KNO 3 and hy- 
 drogen sulphate, what weights of gases are given off? 
 CON 2 H 4 + O 3 = N 2 + 2 H 2 O + CO 3 . 
 
 141. Calculate the weight of iron that would be dis- 
 solved by 100 g. of a solution of hydrochloric acid con- 
 taining 20 % by weight of the gas. 
 
 142. Calculate the weight of zinc sulphate that would 
 be produced by dissolving 10 g. of zinc in sulphuric 
 acid. 
 
 143. How much iodine can be obtained from 236 g. 
 of potassium iodide ? 
 
68 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 144. What weights of iron, iodine, and K 2 CO 3 are 
 needed to make 347 g. of KI ? 
 
 145. What is the weight of potassium chlorate 
 yielded by the chlorine evolved from 100 tons of man- 
 ganese ore containing 60 % of the dioxide? 
 
 146. What weight of potassium bromate can be 
 obtained by neutralizing 520 g. of bromine with pot- 
 ash? 
 
 147. A manufacturer of bleaching powder requires 
 10 tons of chlorine. How much salt, manganese ore 
 containing 59 % of the dioxide, and sulphuric acid con- 
 taining 58 % of real acid will he need? 
 
 148. What weight of MnO 2 , when heated, will yield 
 1 g. of oxygen? 
 
 149. If 2000 g. Cu are heated in air, what weight of 
 oxygen will be used and what weight of CuO will be 
 produced ? 
 
 150. I require 2 Kg. of oxygen ; how much (a) mer- 
 curic oxide, (5) potassium chlorate, and (<?) manganese 
 dioxide, and (c?) sulphuric acid shall I need? 
 
 151. How much KMnO 4 is needed to furnish 1 Ib. of 
 oxygen ? 
 
 152. If 132.74 Kg. of hydrogen are needed to inflate 
 a balloon, what weight of zinc and sulphuric acid will 
 be required to produce this quantity of gas ? 
 
 153. Since 77 % of the weight of the air, freed from 
 moisture and CO 2 , consists of nitrogen, calculate the 
 weight of (a) metallic copper, and (5) of phosphorus 
 required to abstract the oxygen from 1 Ib. of air. 
 
 154. In burning 17 g. of alcohol, find the weight of 
 the products. 
 
WEIGHTS FROM EQUATIONS 69 
 
 155. How much NH 4 NO 3 would produce enough N 2 O 
 for the combustion of 36 g. of carbon ? 
 
 156. How much nitrogen can be produced by the 
 combustion of NH 3 produced by the action of 15 g. of 
 NH 4 C1 on NaOH ? 
 
 157. How much K 2 Cr 2 O 7 will be needed to convert 
 10 g. of FeCl 2 to FeCl 3 ? 
 
 158. How many g. of acetic acid are required to 
 neutralize 6 g. of K 2 CO 3 ? 
 
 159. If a solution contains 30 g. KI, how much chlo- 
 rine would be needed to liberate all the iodine, and how 
 much KC1 would result ? 
 
 160. What weight of SnCl 2 is needed to precipitate 
 completely the gold in 200 g. of AuCl 3 ? 
 
 161. If 100 g. MnO 2 are treated with HC1 in excess, 
 what weight of chlorine is evolved ? If treated with 
 enough NaCl and H 2 SO 4 , how much chloride would be 
 necessary ? 
 
 162. If 300 g. of cinnabar are heated, (#) how much 
 oxygen is needed ; (6) what weight of mercury is left ? 
 
 163. If 63 g. of lead are heated, how many g. of PbO 
 are produced ? 
 
 164. If 100 g. of copper and 100 g. of sulphur are 
 heated together, what substances will be found after 
 combination and how much of each ? 
 
 165. If 32 g. Cu, 103 g. Pb, 12 g. Mg, and 25 g. Fe 
 are each heated in the air till they cease to gain in 
 weight, how many g. will each gain ? 
 
 166. How much iron is needed to throw down all the 
 copper in a CuSO 4 solution containing 160 g. and what 
 weight of FeSO 4 will be formed ? 
 
70 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 167. Calculate the weight of air required to burn a 
 ton of coal possessing the following percentage com- 
 position : carbon, 88.42 ; hydrogen, 5.61 ; oxygen, 
 5.97. 
 
 168. What weight of potassium chlorate is needed to 
 furnish oxygen sufficient to burn the hydrogen evolved 
 by the action of water on 200 g. of calcium ? 
 
 169. If 100 g. of pure iron are burnt in excess of (a) 
 oxygen and (6) chlorine, what is the weight of oxide 
 and chloride produced ? 
 
 170. How much nitre and sulphuric acid shall I need 
 to prepare nitric acid enough to neutralize exactly 5 Ib. 
 of chalk ? 
 
 171. How much pure zinc will be required to prepare 
 1 Kg. of hydrogen ? 
 
 172. What weights of NaOH and H 2 SO 4 are needed 
 to produce 100 g. of Na 2 SO 4 ? 
 
 173. How many g. of sulphuric acid and of nitre are 
 required to make 250 g. of nitric acid ? 
 
 174. How much crystallized microcosmic salt must be 
 ignited to furnish a g. of sodium metaphosphate? 
 
 175. What weights of copper and sulphuric acid are 
 needed to yield 30 g. of sulphurous acid at the stand- 
 ard temperature and pressure? 
 
 176. What weight of iron is contained in 10 tons of 
 pyrite? 
 
 177. What weight of silver chloride will be formed by 
 the reaction of 0.2008 g. of sodium chloride with silver 
 nitrate in solution? 
 
 178. How many tons of coke containing 97 % of 
 carbon are required to reduce 388 tons of hematite ? 
 
WEIGHTS FROM EQUATIONS 71 
 
 179. How much carbon would be necessary to reduce 
 9 g. of copper oxide ? 
 
 180. How much sulphuric acid (80%) should be 
 procurable from 5 tons of pyrite which carries 44 % of 
 sulphur? 
 
 181. Suppose a glass had the formula Na 2 O, CaO, 
 6 SiO 2 , how much sodium carbonate and limestone would 
 be necessary to make 250 Ib. ? 
 
 182. If monazite sand contains 4 % of ThO 2 , how 
 many tons of the sand would be necessary to produce 
 24,000,000 mantles, if each mantle weighs 6 g. ? 
 
 183. How many Ib. of pig iron containing 95% Fe 
 can be made from 2000 Ib. Fe 2 O 3 ? 
 
 184. How much copper oxide would be used and cop- 
 per obtained in preparing 3.2 g. of water? 
 
 185. How much carbon dioxide and disulphide, re- 
 spectively, can be produced from 4 Ib. of pure char- 
 coal? 
 
 186. How much barium dioxide is necessary to make 
 5 Ib. of a* 4 % solution of hydrogen dioxide ? 
 
 187. How much lime is theoretically obtainable from 
 9 tons of limestone which is 97 % pure? 
 
 188. What weight of sodium chloride, when treated 
 with sulphuric acid, will produce 100 g. of sodium sul- 
 phate ? 
 
 189. What weight of sulphuric acid can be manufac- 
 tured from a ton of pyrite ? 
 
 190. What mass of water will be needed to convert 
 142 g. of P 2 O 5 into (a) hydrogen orthophosphate ; 
 (5) hydrogen pyrophosphate ; (<?) hydrogen metaphos- 
 phate ? 
 
72 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 191. What weight of KMnO 4 will be needed to con- 
 vert 139 g. of FeSO 4 , 7 H 2 O into the ferric condition ? 
 
 192. We need 4711 g. common alum ; what weight 
 of "alumina" is needed? 
 
 193. How much of each material would be needed to 
 produce 502 g. of "manganese alum"? 
 
 194. How much water is necessary to convert 55 g. of 
 P 2 O 3 into hydrogen phosphite? 
 
 195. What mass of oxygen can be obtaine.d by heat- 
 ing () 24 g. KC1O 3 ; (5) 174 g. MnO 2 ; (c) 49 g. KC1O 3 
 and MnO 2 ; (d) 100 g. HgO ; (e) 200 g. Cu(NO 3 ) 2 ? 
 
 196. How many g. of commercial HNO 3 (containing 
 68% HNO 3 ) will be needed to decompose (a) 100 g. 
 marble ; (6) 100 g. Na 2 GO 3 ? 
 
 197. What weight of hydrogen can be obtained by 
 the action of 112 g. KOH on potassium formate? 
 
 - 198. Find weight of oxygen needed to burn 150 g. 
 
 of CS 2 . 
 
 199. How many g. arsenic are needed to make 200 g. 
 of arsenibus oxide ? 
 
 200. What weight of magnesium oxide will be pro- 
 duced by burning 0.5 g. of magnesium ribbon? 
 
 201. What weight of oxygen will be obtained by 
 heating 26 g. of potassium chlorate ? 
 
 202. What weight of quicklime can be obtained from 
 1800 Ib. of limestone ? 
 
 203. How much carbon dioxide may be obtained 
 from 22 g. calcium carbonate? 
 
 204. Ten g. of sodium hydroxide are dissolved in 
 water, a volume of hydrochloric acid containing 15 g. 
 
WEIGHTS FROM EQUATIONS 73 
 
 of hydrogen chloride is added, and the mixture is 
 evaporated to dryness. Of what does the residue con- 
 sist and what is the weight of each constituent ? 
 
 205. What weight of silver nitrate could be obtained 
 by dissolving a ten-cent piece, weighing 2.44 g. and 
 containing 90 % silver, in dilute nitric acid and evapo- 
 rating ? 
 
 206. Assume that "thermit" contains 75% iron 
 oxide ; how much of the mixture would be required to 
 produce 6 Ib. of metallic iron? 
 
 207. How many pailf uls of water, 12 Kg. each, would 
 be required to slake 250 Ib. of quicklime ? 
 
 208. How many Ib. of pure calcium cyanamide would 
 be required to produce 40 Ib. of ammonia? 
 
 209. If 80 g. of potassium chlorate are decomposed, 
 the oxygen collected, and magnesium is burned in the 
 oxygen until no gas remains, what weight of magnesium 
 is required ? 
 
 210. What weight of sodium carbonate can be made 
 from 500 Kg. of common salt? 
 
 211. How much nitrogen tetroxide may be made 
 according to theory from 8 g. of lead nitrate? 
 
 212. How much iron could be obtained from 40 g. of 
 Fe 2 O 3 , and what weight of hydrogen would be required 
 to effect this process? 
 
 213. How much AgCl will be formed by the addition 
 of 10 g. of barium chloride to an excess of AgNO 3 ? 
 
 214. How much red lead could be made from 800 Kg. 
 
 of litharge ? 
 
 215. What weight of A1 2 O 3 will be needed to prepare 
 94.8 g. of potash alum? 
 
74 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 216. How much CaSO 4 can be formed from 37 g. of 
 CaCl 2 ? 
 
 217. Calculate the amount of Ba(NO 3 ) 2 necessary to 
 precipitate 120 g. of dilute H 2 SO 4 containing 50 % of 
 water. 
 
 218. How many Ib. of Ag 2 O are needed to make 
 3100 Ib. of oxygen ? 
 
 219. How much K 2 CO 3 is needed to precipitate com- 
 pletely 109.5 g. of CaCl 2 ? 
 
 220. What weight of phosphorus is needed to pro- 
 duce 100 g. of Mg 2 P 2 O 7 ? 
 
 221. What weight of zinc, sodi-um, calcium, iron, 
 and magnesium will be required to produce 10 g. of 
 hydrogen ? 
 
 222. How many g. of CO 2 will combine with 100 g. 
 of CaO to form CaCO 3 ? 
 
 223. If 560 g. of bromine are treated with KOH, 
 what weight of potassium bromate is produced? 
 
 224. If 6 g. of carbon and 22 g. of oxygen are heated 
 in a closed tube, what is the weight of the resulting 
 substances ? 
 
 225. If 294 g. K 2 Cr 2 O 7 are wanted, what weight of 
 K 2 CrO 4 will be used? 
 
 226. If 5.75 g. of silver nitrate are added to 5.75 g. 
 of a solution of hydrochloric acid containing 10.22% 
 HC1, how much silver is precipitated and how much 
 remains in solution? 
 
 227. What weight of oxygen is needed to burn 15 g. 
 of charcoal (90 % C and 4% H)? 
 
 228. What weight of CO 2 is needed to convert 90 
 tons of soda crystals into bicarbonate ? 
 
WEIGHTS FROM EQUATIONS 75 
 
 229. What weight of chlorine could be obtained by 
 acting upon 20 g. of pure manganese dioxide with hy- 
 drochloric acid? 
 
 230. What weight of oxygen could be obtained by 
 the complete decomposition of 100 g. of pure potassium 
 chlorate ? If the chlorate used contained 10 % of its 
 weight of potassium chloride, what would be the differ- 
 ence in the amount of oxygen Obtained? 
 
 231. A solution of nitric acid of sp. gr. 1.46 contains 
 80 % of HNO 3 . What weight of this solution is theo- 
 retically required to dissolve 10 g. of copper oxide? 
 
 232. How much BaO 2 would yield as much oxygen 
 as 250 g. of mercuric oxide? 
 
 233. When 0.542 g. of a salt of copper had been dis- 
 solved in water and precipitated by sodium hydrate, 
 the precipitate was dried and ignited, and it then 
 weighed 0.242 g. What was the percentage of copper 
 in the salt? 
 
 234. A mixture of 4 g. of sodium oxide and 6 g. of 
 sulphur trioxide will give what weight of sodium sul- 
 phate? 
 
 235. A manufacturer of bleaching powder requires 
 400 tons of chlorine. How much salt, manganese con- 
 taining 59 % of the dioxide, and sulphuric acid contain- 
 ing 58 / of real acid will he need ? 
 
 236. What weight of potassium bromate can be ob- 
 tained by neutralizing 1520 g. of bromine with potash? 
 
 237. lodic acid may be obtained by passing a stream 
 of chlorine through water containing iodine in suspen- 
 sion. How much iodine and chlorine will be needed 
 to prepare 100 g. of iodic acid ? 
 
76 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 238. What weight of fluorspar would be required 
 to furnish sufficient hydrogen fluoride (by interaction 
 with sulphuric acid) to convert 5 g. of quartz into 
 silicon fluoride? 
 
 239. Calculate the weight of chlorine, at standard 
 conditions, necessary to give, by interaction with water, 
 an amount of oxygen that will just suffice for the oxida- 
 tion of 10 g. of mercury to mercuric oxide. 
 
 240. What weight of sulphuric acid can be prepared 
 from 100 g. of sulphur ? 
 
 241. Calculate the weight of potassium in a sample 
 of pure sylvite (KC1) which, on being analyzed, gave 
 2.230 g. of chlorine. 
 
 242. What weight of copper is present in a sample 
 of pure copper sulphate which, on being analyzed, gave 
 30.2 g. of sulphur trioxide, SO 3 ? 
 
 243. Calculate the percentage purity of a sample of 
 horn silver which, on being analyzed, gave 74.2% 
 of silver. 
 
 244. When 8.2 g. of crystallized barium chloride 
 and 7 g. of sulphuric acid (70 % H 2 SO 4 ) were brought 
 together in aqueous solution, what weight of barium 
 sulphate was precipitated ? 
 
 245. Compare the weights of aluminum and zinc 
 necessary for the production of equal weights of hydro- 
 gen by interaction with an acid. 
 
 246. Compare the weight of calcium nitride (Ca 3 N 2 ) 
 (in its interaction with water) and the weight of ammo- 
 nium chloride (in its interaction with a base) necessary 
 to give the same weight of ammonia. 
 
WEIGHTS FROM EQUATIONS 77 
 
 247. What relative weights of cupric oxide and cu- 
 prous oxide are procurable from the same weight of 
 copper? 
 
 248. If 2.4 g. of ammonia reduced 17 g. of hot cupric 
 oxide to copper, calculate the reaction quantity of 
 cupric oxide required per molecule of ammonia. 
 
 249. If 3 g. of silver nitrate and 1 g. of potassium 
 chloride were brought together in aqueous solution, 
 what weight of silver chloride would be precipitated ? 
 
 250. If 12 g. of an alloy of aluminum and zinc 
 (containing 33^ % of zinc) were placed in a vessel con- 
 taining 180 g. of hydrochloric acid (35 % HC1), what 
 volume of hydrogen, at standard conditions, would be 
 liberated ? 
 
 251. A specimen of silver containing 3% copper 
 weighed 9.8 g. After solution in nitric acid, an excess 
 of sodium chloride was added to it. Calculate the 
 weight of the silver chloride precipitated. 
 
 252. What weight of potassium hydroxide may be pre- 
 pared by the action of 100 g. of potassium upon water ? 
 
 253. What weight of potassium will be required in 
 the preparation of 20 g. of potassium carbonate ? 
 
 254. What weight of magnesium chloride may be 
 obtained by the action of hydrochloric acid upon 10 g. 
 of magnesium carbonate ? What weight of carbon 
 dioxide will be liberated ? 
 
 255. What weight of sulphur dioxide can be obtained 
 by the action of an acid upon 250 g. of sodium sulphite ? 
 
 256. If sodium nitrate, ammonium nitrate, and potas- 
 sium nitrate were the same price per lb., which would 
 be cheapest to use for preparing nitric acid, and why ? 
 
78 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 257. How much sulphuric acid and potassium nitrate 
 would be required in order to prepare 100 g. of nitric 
 acid? 
 
 258. What weight of chrome-alum may be obtained 
 from 20 g. of crystallized potassium sulphite and an 
 excess of chromium sulphate ? 
 
 259. What weight of ammonium-magnesium phos- 
 phate (NH 4 MgPO 4 , 6 H 2 O) could be formed from a solu- 
 tion containing 50 g. of crystallized magnesium sulphate 
 and an excess of ammonia and sodium phosphate? 
 
 260. What weight of iron-ammonium alum may be 
 formed when 12 g. of ammonium sulphate and 30 g. 
 of ferric sulphate are brought together in concentrated 
 aqueous solution ? 
 
 261. When 100 g. of mercury and 20 g. of sulphur 
 are rubbed together, what weight of mercuric sulphide 
 may be formed ? 
 
 262. A solution containing 5 g. of potassium iodide is 
 precipitated with silver nitrate. What will be the 
 weight of the precipitate of silver iodide ? 
 
 263. What quantities of nitre and Chili saltpeter, 
 respectively, will be required to obtain the maximum 
 quantity of nitric acid by reaction with 140 Kg. of 97 % 
 sulphuric acid ? 
 
 264. Calculate the weight of air required to burn 1 
 ton of coal possessing the following percentage com- 
 position : carbon, 88.42; hydrogen, 5.61 ; oxygen, 5.97. 
 
 265. How much marble and hydrochloric acid con- 
 taining 22 % HC1 are needed to yield 10 g. of carbon 
 dioxide ? 
 
WEIGHTS FROM EQUATIONS 79 
 
 266. A piece of metallic iron immersed in a solution 
 of copper for a long time, in order to precipitate all the 
 copper, was found to have lost in weight 0.52 g. 
 What was the amount of copper in the solution ? 
 
 267. A solution of mercuric chloride contains 80 g. 
 of the salt per 1. ; sodium hydrate is added in excess to 
 175 cc. of the solution ; what will the precipitate weigh 
 if collected and dried ? 
 
 268. How many tons of oil of vitriol containing 70 % 
 H 2 SO 4 are needed to convert 100 tons of salt into salt 
 cake ? 
 
 269. What increase in weight will occur on burning 
 10 g. of phosphorus in a tube through which oxygen is 
 passed, supposing that none of the product is lost ? 
 
 270. How many g. of iodine will be liberated from 
 an excess of a saturated solution of potassium iodide, 
 into which the gas evolved from heating 4.34 g. of 
 manganese dioxide with hydrochloric acid is passed ? 
 
 271. What weight of potassium dichromate must be 
 heated with hydrochloric acid in order to evolve suffi- 
 cient chlorine to liberate the iodine from 1.656 g. of 
 potassium iodide ? 
 
CHAPTER VII 
 
 Volumes from Equations 
 
 1. What weight of 95 % alcohol is needed to yield 
 20 m. 3 of ethylene at + 94 F. and 730 mm.? 
 
 2. A 1. of water is acted upon by phosphorus ' tri- 
 bromide; what will be the weight of the products and 
 the volumes of the gaseous ones at + 4 C. and 760 
 mm.? 
 
 3. A tank ^ m. long, | m. wide, and ^ m. deep is 
 filled with water and the water decomposed. What 
 volumes of hydrogen and of oxygen result, if measured 
 at -13 C. and 790 mm.? 
 
 4. If 130 1. of CO 2 are passed through a KOH 
 solution, how many g. of KOH will be converted into 
 K 2 C0 3 ? 
 
 5. If 100 g. of Na 2 CO 3 -are 'treated with HC1, how 
 many g. of salt and how many 1. of CO 2 will be 
 formed ? 
 
 6. If 1 m. 3 of CO 2 is absorbed by Ca(OH) 2 , what 
 weight of CaCO 3 will be formed? 
 
 7. An ore contains 67 A % of MnO 2 ; what volume 
 of chlorine could be obtained by treating 300 tons of 
 this ore with HC1? 
 
 8. How much acetic acid must be decomposed in 
 order to obtain 100 1. of CH 4 ? 
 
 80 
 
VOLUMES FROM EQUATIONS 81 
 
 9. From 100 Ib. of pure limestone how many 1. of 
 CO 2 can be obtained? What weight of lime? 
 
 10. 2 KNO 3 -}- 3 C + S = 3 CO 2 + N 2 + K 2 S. In the 
 above equation find the weights and volumes of the 
 gases produced and the weight of carbon and sulphur 
 when 10 g. of KNO 3 are used. 
 
 11. How much phosphorus can be burned in 4 1. of 
 " laughing gas " measured at + 14 C. ? 
 
 12. What weight of HBr will result if 1 m 3 . of 
 hydrogen is caused to unite with bromine vapor by 
 passing the mixture over a catalytic agent? 
 
 13. How many g. of zinc are necessary for the pro- 
 duction, by the action of muriatic acid, of 90 1. of 
 hydrogen measured under standard conditions? 
 
 14. If 19 g. of CS 2 are burned, what are the weights 
 and volumes of the products ? 
 
 is. 3 Cu 2 + 14 HN0 3 = 6 Cu(NO 3 ) 2 + 7 H 2 O + 
 2 NO. 100 g. of Cu 2 O are used. Find volume of the 
 gas produced. 
 
 16. What volume of nitrous oxide measured at C. 
 and 750 mm. would be evolved by the decomposition of 
 10 g. of ammonium nitrate? 
 
 17. When 12 g. of carbon burn in the air, find 
 the volume of the resulting gas at 1 atmosphere and 
 0C. 
 
 18. A balloon of 100,000 ft. 3 capacity is to be filled 
 with hydrogen; how many Ib. of zinc and sulphuric 
 acid will be needed? 
 
 19. How much water can be decomposed by 20.7 g. 
 of sodium, and what volume of hydrogen would be set 
 free? 
 
82 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 20. What volume of hydrogen will unite with 24 g. 
 of oxygen to form water ? What volume of hydrogen 
 and of oxygen could be obtained by the electrolysis of 
 10 g. of water? 
 
 21. With what weight of hydrogen will 30 g. of 
 oxygen unite to form water? 
 
 22. With how much sulphuric acid must zinc be 
 treated in order to obtain 16,250 cc. of hydrogen ? Find 
 weight of ZnSO 4 . 
 
 23. If a tube containing copper oxide weighs before 
 hydrogen is passed through it 15.846 g., and after 
 the hydrogen has been passed 12.239 g., how many 1. 
 of hydrogen have united with the oxygen of the copper 
 oxide? How much water has been formed? 
 
 24. Find the number of 1. of gas given off by the 
 action of 130.8 g. of Zn on H 2 SO 4 . 
 
 25. Given 10 Kg. of iron to be acted upon by sulphuric 
 acid, what weight of acid is needed, and what is the 
 volume of hydrogen secured at 6 C. and 780 mm. 
 pressure? 
 
 26. How many 1. of hydrogen at C. and 760 mm. 
 pressure may be secured from 2000 g. of HC1 ? 
 
 27. What weight of NH 4 NO 3 must be used to give 
 45 1. of N 2 O under standard conditions'? 
 
 28. How many 1. of hydrogen, under standard condi- 
 tions, will result from the electrolysis of 18 g. of water? 
 
 29. How many g. of sulphur must be burned to yield 
 100 1. of sulphur dioxide under standard conditions? 
 
 30. What would be the volume, under standard con- 
 ditions, of the hydrogen liberated in the decomposition 
 of 30 g. of water by means of sodium ? 
 
VOLUMES FROM EQUATIONS 83 
 
 31. What volume of hydrochloric acid, under stand- 
 ard conditions, can be obtained by the action of sul- 
 phuric acid upon 150 g. of salt? 
 
 32. What volume of chlorine, measured under stand- 
 ard conditions, will convert JjO g. of potassium hydroxide 
 into chloride and chlorate according to the reaction : 
 
 6 KOH + 3 C1 2 = 5 KC1 + KC1O 3 + 3 H 2 O? 
 
 33. How many cc. of marble, CaCO 3 (sp. gr. 2.70), 
 must be dissolved in HC1 to give 5 1. of CO 2 ? 
 
 34. How many g. of air, approximately, ought it to 
 take to burn 10 1. of gaseous C 3 H g , if ^ of the volume 
 of the air is oxygen? 
 
 35. (a) How many Kg. of CO 2 will form in the com- 
 bustion of a cylindrical tank of liquid acetylene, C 2 H 2 , 
 which is 15 cm. in diameter and 18 dm. high, if its 
 sp. gr. is 0.8? (5) If the CO 2 is absorbed by lime 
 water, how many Kg. of CaCO 3 would form? (<?) How 
 many days will this tank of C 2 H 2 serve to light a house 
 with 6 gas jets, each running 5 hours and burning J ft. 3 
 per hour, if 1 ft. 3 equals 27,000 cc.? 
 
 36. What volume of sulphur dioxide would result 
 from heating in the air 1 ton of pure iron pyrites, assum- 
 ing that all of the sulphur in the pyrites is converted 
 into sulphur dioxide ? 
 
 37. What volume of hydrogen sulphide will be 
 formed upon treating 40 g. of ferrous sulphide, FeS, 
 with hydrochloric acid? 
 
 38. What volume and what weight of sulphur di- 
 oxide will be formed upon burning 1 1. of hydrogen 
 sulphide ? 
 
84 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 39. Under a barometric pressure of 740 mm. at + 20 
 C., what weight of ammonium nitrate must be decom- 
 posed to generate sufficient nitrous oxide to fill a balloon 
 holding 200 1. ? 
 
 40. What weight of carbon will be required to com- 
 pletely convert into carbon dioxide 20 1. of oxygen 
 measured under a pressure of 780 mm. of mercury at 
 + 30 C. ? What volume of carbon dioxide, under the 
 same conditions, will be formed ? 
 
 41. Excess of carbon is thrown into 100 g. of fused 
 KNO 3 . What volume of nitrogen and of CO 2 is 
 evolved ? 
 
 4 KNO 3 + 50 = 2 K 2 CO 3 + 2 N 2 + 3 CO 2 . 
 
 42. Find the number of 1. of water needed to slake a 
 bin of lime containing 1376 Kg. 
 
 43. It is desired to fill with oxygen at + 35 C. and 
 530 mm. a gas-holder, the capacity of which is 45 1. ; 
 what weight of KC1O 3 is requisite? 
 
 44. A Kg. of KC1O 3 will yield what weight of 
 oxygen ; what volume at + 24 C. and 736 mm. ? 
 
 45. If 256 g. of sodium peroxide are decomposed by 
 water, what is the volume of the oxygen secured at 
 + 21 C. and 710 mm. ; at - 80 C. and 1410 mm. ? 
 
 46. What volume of hydrogen may be secured from 
 12 Kg. of water, with the aid of potassium, the hydrogen 
 to be measured at + 25 C. and 780 mm. ? 
 
 47. What weights of water and of potassium are 
 needed to generate 8 1. of hydrogen at + 25 C. and 
 760mm.? 
 
 48. How many 1. of hydrogen at + 22 C. and 
 714 mm. will 98 g. of hydrochloric acid yield ? 
 
VOLUMES FROM EQUATIONS 85 
 
 49. How much zinc is needed to prepare 100 1. of 
 hydrogen at C. and 740 mm. ? 
 
 50. Am. 3 gas-holder is to be* filled with oxygen at 
 + 100 C. and 721 mm. What weight of Pb(NO 3 ) 2 
 is needed to prepare it? 
 
 51. If 10 1. of hydrogen at + 15 C. are burned, what 
 volume of steam at + 300 C. is formed? 
 
 52. How many 1. of chlorine can be obtained by 
 treating 50 g. of manganese dioxide with hydrochloric 
 acid? 
 
 53. What volume of arsine will result when 150 mg. 
 arsenic trioxide is acted upon by nascent hydrogen? 
 
 54. How much lead sulphide can be precipitated by 
 17 1. of hydrogen sulphide ? 
 
 55. What volume of sulphur vapor would result from 
 the decomposition of a 1. of H 2 S at + 500 C. if the 
 density of S is 96 and its atomic weight is 32 ? 
 
 56. What volume of zinc vapor will unite with 
 300 cc. of oxygen to form zinc oxide? Zn has vapor 
 density of 32.5; atomic weight 65. 
 
 57. How much phosphoric fluoride by volume can 
 be obtained from 100 g. of phosphorus pentachloride ? 
 
 5 AsF 3 + 3 PC1 5 = 5 AsCI 3 + 3 PF 5 . 
 
 Supposing all the products to be gases, find the vol- 
 umes. 
 
 58. How many cc. of solid arsenic (sp. gr. 5.73) could 
 be obtained from 1250 cc. of arsine at a temperature of 
 + 105C.? 
 
 59. If 425 1. and 328 cc. of oxygen at + 24 C. and 
 658 mm. are wanted, what weight of BaO 2 is needed 
 to make that amount ? 
 
86 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 60. If 752 1. of oxygen at + 19 C. and 729 mm. are 
 wanted, what weight of water must be decomposed to 
 secure that amount, and what volume of hydrogen is 
 obtained at the same time ? 
 
 61. Three 1. of water are to be decomposed. What 
 volumes of hydrogen and oxygen result at 21 C. and 
 790 mm. ? 
 
 62. The hydrogen secured from 100 Ib. of sulphuric 
 acid is burned. What weight of water results ? 
 
 63. The hydrogen derived from 2 1. of water is 
 burned. What is the weight of the product? 
 
 64. The hydrogen derivable from 98 Kg. of pure sul- 
 phuric acid is to be burned ; what is the weight of the 
 product? What is its volume at + 4 C. and 760 mm. ; 
 at + 150 C. and 754 mm. ? 
 
 65. How much ammonium nitrate is needed to pre- 
 pare 100 1. of nitrous oxide at 5 C. and 600 mm. ? 
 
 66. How much copper is needed to prepare 100 1. of 
 nitric oxide at - 100 C. and 760 mm. ? 
 
 67. What weight of phosphorus, if all is converted, 
 is necessary to produce 100 1. of phosphine at + 68 F. 
 and 720 mm. ? 
 
 68. What volumes of hydrogen and oxygen, respec- 
 tively, result from the decomposition of 100 1. of water 
 vapor at + 200 C. ? 
 
 69. What weight of carbon is necessary to reduce. 20 
 g. of carbon dioxide to carbon monoxide ? How many 
 1. of air at + 22 C. and 760 mm. are required to burn 
 the monoxide thus formed to the dioxide ? 
 
VOLUMES FROM EQUATIONS 87 
 
 70. What volume of oxygen, measured under stand- 
 ard conditions, will be evolved when 108 g. of mercuric 
 oxide are decomposed by heating ? 
 
 71. If 15 Kg. of H 2 SO 4 are worked up by the aid of 
 copper into sulphur dioxide, what weight of Cu is 
 needed, and what weights and volumes of the products 
 result at + 35 C. and 730 mm. ? 
 
 72. A 1. of chlorine measured at + 25 C. and 753 
 mm. is used to expel the iodine from potassium iodine. 
 What weight of iodine is expelled ? 
 
 73. Find, under standard conditions, the volume of the 
 gases resulting from the electrolysis of 72 g. of water. 
 
 74. If 50 gal. of carbon monoxide are burned, what 
 volume of oxygen at + 48 C. and 675 mm. is necessary, 
 and what volume of carbon dioxide is secured ? 
 
 75. One hundred g. of chlorine are to be united with 
 hydrogen. What volume of hydrogen is needed at 
 4- 150 C. and 735 mm., and what volume of hydro- 
 chloric acid gas results ? 
 
 76. The hydrogen sulphide secured from 55 Kg. of 
 ferrous sulphide is decomposed. What volume of hydro- 
 gen results at C. and 760 mm. ; at + 75 C. and 780 
 mm.? 
 
 77. If 1500 g. of HC1 are decomposed, what volumes 
 of H and of Cl are secured at + 28 C. and 790 mm. ? 
 
 78. The HC1 securable from 550 g. of common salt is 
 decomposed. What volumes of H and Cl result at 
 
 -20C. and 778 mm.? 
 
 79. The water resulting from the combustion of 1 g. 
 of hydrogen is decomposed. What are the volumes of 
 H and O at + 423 6 C. and 787 mm. ? 
 
88 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 80. What weight of material is required to secure 
 500 1. of ammonia at C. and 700 mm. ? 
 
 81. If 500 g. of oxalic acid are decomposed with sul- 
 phuric acid, what volumes of carbon monoxide and 
 dioxide result if measured at 21 F. and 640 mm. are 
 obtained ? 
 
 82. How much ferrous sulphide is needed to pre- 
 pare 100 1. of hydrogen sulphide at - 10 C. and 800 
 mm. ? 
 
 83. If 13,720 cc. of hydrogen chloride at - 10 C. 
 and 730 mm. are decomposed by electricity, what are 
 the volumes and weights of the products ? 
 
 84. What weight of calcium carbide must be em- 
 ployed if we wish to fill with acetylene gas a reservoir, 
 12 m. by 10 m. by 60 cm., at + 28 C. and 760 mm. ? 
 
 85. What volume of nitrous oxide, measured at C. 
 and 780 mm., may be obtained from 10 Kg. of ammonium 
 nitrate ? 
 
 86. How many 1. of chlorine at -}- 21 C. and 750 mm. 
 are needed to manufacture 10 Kg. of potassium chlorate, 
 provided there is no loss ? 
 
 87. What weight of calcium carbide must be em- 
 ployed to fill with acetylene gas a gas-holder that con- 
 tains 10,000 m. 3 at + 18 C. and 750 mm. ? 
 
 88. The hydrogen chloride secured from 210 Kg. of 
 sodium chloride is employed for preparing hydrogen. 
 What is the volume procurable at +1200C. and 2.5 
 atmospheric pressure ? 
 
 89. What volume of hydrogen at -f 40 C. and 715 
 mm. will 1 Kg. of sodium liberate from water? 
 
VOLUMES FROM EQUATIONS 89 
 
 90. What volume of arsine at +20 C. and 760 mm. 
 results from the action of nascent hydrogen upon 10 g. 
 of arsenious oxide ? 
 
 91. What volume of hydrogen sulphide at + 110 C. 
 and 660 mm. may be made from 210 Kg. of ferrous sul- 
 phide ? 
 
 92. What volume of NH 3 may be obtained from 430 g. 
 of NH 4 C1? 
 
 93. What volume of oxygen is needed at 0C. and 
 760 mm. to burn completely 42 1. of hydrogen sulphide 
 measured at + 20 C. and 780 mm.? 
 
 94. A container measuring 50 cm. by 9 dm. by 300 
 mm. is filled with HC1 gas at + 20 C. and 740 mm. 
 A precisely similar measure of ammonia is introduced ; 
 what weight of ammonium chloride is formed ? What 
 is left over and how much ? 
 
 95. What volume of gaseous products, measured at 
 4- 150 C. and 760 mm., is secured by the decomposition 
 by heat of 2 Kg. of ammonium nitrate ? 
 
 96. One Kg. of phosphorous acid is to be made by 
 acting upon phosphorus tribromide with water. What 
 weight of the tribromide is needed, and what volume of 
 hydrogen bromide is produced ? 
 
 97. If 1300 1. of hydrogen sulphide at +88C. and 
 742 mm. are decomposed, what weight of sulphur re- 
 sults? What is the volume of the resultant sulphur 
 measured at +1450 C. and 760 mm.? 
 
 98. What volumes of hydrogen and nitrogen, meas- 
 ured at 10 C. and 730 mm., result if we decompose 
 by electricity all of the ammonia that may be secured 
 from 1000 g. of ammonium sulphate ? 
 
90 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 99. Given 20 1. of sulphur vapor at + 500 C., what 
 quantity, by weight, of sulphur trioxide can be made 
 from it ? 
 
 100. To secure 100 Kg. of H 2 S at - 10 C. and 750 
 mm., what weight of Na 2 S and of hydrochloric acid is 
 needed ? And what other products are secured? 
 
 101. How many g. of sulphur are needed to produce 
 110 1. of sulphur dioxide at + 360 F. and 739 mm.? 
 
 102. If 10,000 m. 3 of hydrogen sulphide at two at- 
 mospheres pressure and + 10 C. are wanted, what 
 weight of materials is needed to make it ? 
 
 103. What volume of hydrogen chloride is formed 
 when 10 1. of chlorine combine with hydrogen ? 
 
 104. What volume of nitric oxide, measured at 743 
 mm. and + 18 C., will be produced by treating 18 g. 
 of metallic copper with an excess of nitric acid ? 
 
 105. How many 1. of oxygen are required to burn 
 3 1. of AsH 3 , and what will be the weight of each of 
 the products ? 
 
 106. What volume of carbon dioxide, measured at 
 750 mm. pressure and +20C., will be formed when 
 17 g. of a candle, 85 % C and 15 % H, is burned ? 
 
 107. A steel cylinder of 4 ft. 3 capacity is to be 
 filled with carbon dioxide under a pressure of 150 Ib. 
 to the in. 2 . What weight of marble and hydrochloric 
 acid would be needed to produce the necessary amount 
 of gas ? 
 
 108. How many 1. of acetylene can be obtained from 
 50 g. of calcium carbide that is 93 % pure, if the gas is 
 evolved at a temperature of + 40 C. and a pressure 
 of 1 J atmospheres ? 
 
VOLUMES FROM EQUATIONS 91 
 
 109. What volume of sulphur dioxide at + 20 C. 
 and 740 mm. can be obtained by the action of 20 g. 
 of sulphuric acid upon copper ? 
 
 110. How many 1. of carbon dioxide would result 
 from burning 5.384 g. of carbon? 
 
 111. What volume of oxygen will be required to 
 burn 1 Kg. of carbon ? 
 
 112. What volume of air, of 21 % oxygen by volume, 
 is needed to burn completely 1 ton of anthracite coal, 
 assumed to be pure carbon ? 
 
 113. How many 1. of chlorine can be obtained from 
 34 g. of salt ? 
 
 114. What volume of oxygen, measured at + 15 C. 
 and 772 mm. pressure, can be obtained from 100 cc. of 
 sulphuric acid (sp. gr. 1.84)? 
 
 2 K 2 Cr 2 7 + 8 H 2 S0 4 = 2 K 2 SO 4 + 2 Cr 2 (SO 4 ) 3 
 
 + 8 H 2 + 3 2 . 
 
 115. How many 1. of air will be required to burn 
 5 g. of phosphorus? 
 
 116. If 10 1. of hydrofluoric acid gas were made from 
 CaF 2 and H 2 SO 4 , how much CaSO 4 was made at the 
 same time? 
 
 117. What volume of nitrous oxide, measured at 
 C. and 750 mm., would be evolved by the decomposi- 
 tion of 10 g. of ammonium nitrate ? 
 
 118. What volume of carbon dioxide, under standard 
 conditions, can be obtained from exactly 10 g. of 
 calcium carbonate? 
 
 119. If 12 g. of carbon are burned to carbon dioxide, 
 what will be the volume of the gas compared with 1 g. 
 of hydrogen at the same temperature and pressure ? 
 
92 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 120. From 2078 g. of sodium chloride what volume 
 of chlorine can be obtained ? 
 
 121. If 9.6 g. of sulphur are heated in hydrogen, 
 what volume of hydrogen sulphide is formed ? 
 
 122. What volume of hydrogen, under normal condi- 
 tions of temperature and pressure, can be obtained from 
 10 . of pure zinc ? 
 
 123. Calculate the number of g. of ferrous carbonate 
 required to react with sulphuric acid in order to set 
 free 60 1. of carbon dioxide. 
 
 124. If 40 g. of Ca react with water, what is the 
 weight and volume of hydrogen? 
 
 125. If 600 g. of MnO 2 are decomposed by heat, 
 what is the volume of O at + 13 C. and 781 mm. ? 
 
 126. If 55.8 1. of hydrogen at C. and 760 mm. 
 are required, how much zinc and KOH are needed 
 for its formation ? 
 
 127. If 168 g. of MgCO 3 are heated and the CO 2 
 is passed into KOH solution, what weight of K 2 CO 3 
 will be formed ? 
 
 128. If 147 g. K 2 Cr 2 O 7 are heated with H 2 SO 4 , what 
 will be the volume and weight of gas evolved ? 
 
 129. How much alcohol should be burned to give 
 13 1. of steam ? 
 
 130. If 1000 cc. of H 2 S burn in the air, find (a) 
 weight and volume of oxygen used, and (b) products 
 formed. 
 
 131. If 16 1. of SO 2 are produced by burning a piece 
 of sulphur, how heavy was the sulphur ? 
 
 132. What volume of chlorine is required to unite 
 with 71 g. of gold to produce auric chloride ? 
 
VOLUMES FROM EQUATIONS 93 
 
 133. How many 1. of oxygen at C. and 760 mm. 
 could be obtained from a pailful of water, the water 
 weighing 12 Kg. ? 
 
 134. How much salt is necessary to produce 480 g. 
 of chlorine, and how much space would be filled by that 
 amount of chlorine at + 20 C. and 755 mm. pressure ? 
 
 135. The sp. gr. of acetylene is 0.92. What volume 
 would be occupied, at + 20 C. and 750 mm., by the 
 gas generated from 480 g. of calcium carbide, 95 % 
 pure? 
 
 136. What weight of potassium chlorate is necessary 
 to yield 6 1. of oxygen measured over water at 
 + 18.1 C. and 759.9 mm.? 
 
 137. If 2 g. of steam are passed over red-hot iron, 
 what volume of hydrogen at + 10 C. and 770 mm. is 
 formed ? 
 
 4 H 2 + 3 Fe = Fe 3 O 4 + 4 H 2 . 
 
 138. What weight of sodium would be necessary to 
 liberate 75 cc. of hydrogen at C. and 760 mm. by 
 reacting with water ? 
 
 139. What volume of oxygen at C. and 760 mm. 
 would be liberated by heating 1.05 g. of mercuric 
 oxide ? 
 
 140. What volume of hydrogen, measured over water 
 at + 17.3 C. and 758.2 mm., will be generated by the 
 reaction of 20 g. of zinc with dilute sulphuric acid ? 
 
 141. What volume of "laughing gas," measured at 
 4- 20 C. and 750 mm., may be made from 12 g. of 
 ammonium nitrate ? 
 
 142. How much phosphorus is required to remove 
 the oxygen from a 1. of air ? 
 
94 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 143. How much alcohol will be needed to use up 
 during combustion 116 g. of oxygen ? 
 
 144. Find the volume of oxygen needed to burn com- 
 pletely 20 g. of alcohol and the volumes of the products. 
 
 145. What volume of phosphine is evolved during 
 the solution of 62 g. of phosphorus in Ba(OH) 2 solu- 
 tion ? 
 
 146. Calculate the volume of ammonia obtainable 
 from 126 g. of HNO 3 . 
 
 147. If 5580 cc. of HF are passed over heated so- 
 dium, how much of each product is obtained? 
 
 148. An excess of Ag 2 O is thrown into 136 g. of a 
 solution of H 2 O 2 containing 75 % water ; what gas is 
 evolved, and what will be its volume at 133 C. and 
 1520 mm. ? 
 
 149. If 55 g. of HgO are heated, what is the volume 
 of the oxygen at 667 mm. and + 22 C. ? 
 
 150. To produce 112 1. of hydrogen from steam, how 
 much charcoal must be used? 
 
 151. MnO 2 is treated with 10 1. of HC1. Find 
 weight and volume of chlorine produced. 
 
 152. What weight of ammonium sulphate would be 
 produced by neutralizing 100 g. of pure sulphuric acid 
 with ammonia? 
 
 153. How much carbon dioxide by weight and by 
 volume can be prepared from 275 g. of calcium carbon- 
 ate? 
 
 154. What volume of chlorine at + 15 C. must be 
 passed over 20 g. of AgNO 3 to obtain N 2 O 5 ? 
 
 C1 2 + 2 AgN0 3 = 2 AgCl + + N 2 O 5 . 
 
VOLUMES FROM EQUATIONS 95 
 
 155. What volume of H 2 S would be needed to pro- 
 duce 10 g. of CuS from a CuSO 4 solution? 
 
 156. Calculate the volume of carbon dioxide, meas- 
 ured at C. and 760 mm., that can be made from 50 g. 
 of calcium carbonate and an excess of hydrochloric acid. 
 
 157. Into what volume of oxygen will 96 g. of ozone 
 break up? 
 
 158. If 500 g. of hydrogen are needed, how much 
 steam is required? 
 
 159. If 5 g. of zinc are dissolved in acid, how many 
 cc. of hydrogen are freed when measured at + 10 C. 
 and 750 mm. ? 
 
 160. How many cc. of HC1 solution, containing 
 240 g. of HC1 per 1., will be required to decompose 
 2500 g. of CaCO 3 ? 
 
 161. How many 1. of (a) hydrogen and (5) carbon 
 monoxide, at + 10 C. and 750 mm., can be obtained 
 by passing steam over 24 g. red-hot charcoal ? 
 
 162. If 13 g. of sodium are placed on water, the con- 
 ditions being + 11 C. and 700 mm., how many m. 3 of 
 gas are liberated? 
 
 163. If 2 g. of potassium are heated in NH 3 , how 
 much potassium amide and what volume of hydrogen 
 at +15 C. are formed? 
 
 K + NH 8 = KH 2 N + H. 
 
 164. What weight of nitric oxide would be needed 
 to unite with the oxygen of the air in a 10 1. flask? 
 
 165. If a man exhale one m. 3 of CO 2 in an hour, at 
 + 16 C., how long will it take him to produce 5 Kg. 
 of the gas? 
 
96 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 166. When 10 g. of sulphur burn in contact with 
 hydrogen, what volume and weight of H 2 S could be 
 produced? 
 
 167. If 2 1. of nitrosyl chloride at -f- 15 C. are passed 
 over warm lunar caustic, how much N 2 O 5 is formed? 
 
 NO 2 C1 + AgNO 3 = AgCl + N 2 O 5 . 
 
 168. A balloon holds 15,000 1. What weight of 
 NH 4 NO 3 will give enough gas to fill the balloon at 
 + 20 C. and 600 mm. ? 
 
 169. Find weight of copper needed to produce 15 1. 
 of NO at 871 mm. and + 22 C. 
 
 170. If 20 1. of oxygen under 420 mm. pressure will 
 be enough to burn completely 20 g. of phosphorus, at 
 what temperature is it? 
 
 171. If 300 cc. of NH 3 react with chlorine, what volume 
 of nitrogen is obtained at 6 C. and 327 mm. pressure? 
 
 172. What volume of hydrogen is required by 19 g. 
 of chlorine to produce hydrochloric acid ? 
 
 173. If 300 cc. of chlorine are obtained from the elec- 
 trolysis of HC1, what weight and volume of hydrogen 
 are given off, and what weight of HC1 is used? 
 
 174. If 130 g. of pyrolusite (90.7 % pure) are heated 
 with an excess of HC1, what is the volume of the gas 
 given off? 
 
 175. A tank contains 6m. 3 . How many g. of zinc 
 and acid are needed to fill it with hydrogen at standard 
 conditions? 
 
 176. If 1 g. each of K, Li, Na, and Ca are placed in 
 water separately and the hydrogen of each is measured, 
 which metal will give the greatest yield in cc. ? Find 
 weight from each. 
 
VOLUMES FROM AQUATIONS 97 
 
 177. Find weight of 171. of ethylene. What volume 
 of oxygen would be needed to burn it ? 
 
 178. How many g. and 1. of oxygen will be given by 
 300 g. of K 2 Cr 2 O 7 + H 2 SO 4 in excess ? 
 
 179. How many 1. of chlorine will be liberated by 
 treating 39 g. of KC1O 3 with sufficient HC1 solution to 
 decompose it? 
 
 180. If 98 g. of H 2 SO 4 react on K 2 Cr 2 O 7 , what 
 volume of oxygen, measured at + 12 C. and T99 mm., 
 will be evolved ? 
 
 181. Calculate the weight of NH 4 NO 3 required to 
 produce 1900 cc. of N 2 O, measured at + 12 C. and 710 
 mm. 
 
 182. If 500 g. of marble are treated with HC1, how 
 many g. of HC1 are needed, and what will be the 
 volume of the resulting gas at + 15 C. and 740 
 mm.? 
 
 183. How many 1. of muriatic acid will be liberated 
 by treating 585 g. of salt with H 2 SO 4 ? 
 
 184. The iodine in 100 volumes of HI is liberated in 
 succession by chlorine and oxygen. Find the volume 
 of chlorine and of oxygen used. 
 
 185. How much SnCl 2 must be electrolyzed to give 
 chlorine enough to convert 180 g. of antimony into 
 SbCl 3 ? 
 
 186. When 100 g. of NH 4 NO 3 are decomposed, find 
 the volume of N 2 O measured at -f 1 C. and 800 mm. 
 
 187. If 50 g. of CO are needed, what volume of CO 2 
 should be passed over red-hot coke ? 
 
 188. What volume of H 2 S, measured at 31 C. and 
 777 mm., can be obtained from 10 g. of FeS? 
 
98 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 189. What volume of chlorine at +27 C. and 777 
 mm. will be required to convert 232 g. of Bi 2 O 3 into 
 Bi 2 8 ? 
 
 190. What volume of NH 3 will 50 g. of lime liberate 
 from an ammonia salt? 
 
 191. What volumes and weights of hydrogen and 
 oxygen are contained in 13 1. of water? 
 
 192. If 10 g. of graphite burn in oxygen, what is the 
 weight and volume of CO 2 formed? 
 
 193. What weight of salt will yield (a) 17 1. chlo- 
 rine; (6) 13 g. Na 2 SO 4 ; (c) 30 g. MnSO 4 ; (d) 3 1. of 
 water ? 
 
 194. If 30 cc. of air and 60 cc. of hydrogen are ex- 
 ploded, what is the volume and weight of the residue ? 
 
 195. If 16 g. of HgO are heated, what is the weight 
 of residue; the weight and volume of gas given off? 
 
 196. If 100 g. of steam are passed over red-hot iron, 
 what volume of hydrogen at +10 C. and 742 mm. is 
 formed ? 
 
 197. What volume of oxygen can be obtained from 
 20 g. of manganese dioxide by heating it alone? 
 
 198. What volume of oxygen at +10 C. and 743 
 mm. can be obtained by the decomposition of a 1. of 
 sulphuric acid possessing a density of 1.84 at C.? 
 
 199. What weight of hydrochloric acid is produced 
 in the manufacture of 100 tons of salt cake? What 
 volume of gas escapes, supposing the manufacturer to 
 condense only 92 % of the quantity evolved? 
 
 200. What volume of oxygen at C. and 760 mm. 
 can be theoretically obtained from 1 Ib. of bleaching 
 powder ? 
 
VOLUMES FROM EQUATIONS 99 
 
 201. If 1 g. of phosphorus is to be converted into 
 the pentachloride, how many 1. of chlorine are re- 
 quired? 
 
 202. How much marble and hydrochloric acid con- 
 taining 22 % HC1 are needed to yield 10 1. of carbon 
 dioxide at + 15 C. and 760 mm. barometric pressure? 
 
 203. Calculate the volume of nitrogen monoxide at 
 + 15 C. and 740 mm. produced on heating 30 g. of 
 ammonium nitrate. 
 
 204. I require 10 1. of carbon monoxide at C. and 
 760 mm. pressure. How many g. of (a) oxalic acid; 
 (6) of formic acid ; and (c) of potassium ferrocyanide 
 shall I need ? 
 
 205. A gas bag has a capacity of 45 1. ; how much 
 manganese dioxide containing 70 % of MnO 2 is required 
 to fill it with oxygen at 4-15 C. and 760 mm.? 
 
 206. How many cc. of oxygen and hydrogen, measured 
 at +12 C. and under a pressure of 762 mm., can be 
 obtained by the electrolysis of 10 g. of water? 
 
 207. What weight of ammonia and of chlorine is 
 needed to produce a 1. of nitrogen ? 
 
 208. If 100 g. of steam are passed over 1000 g. of 
 red-hot iron wire, what volume of hydrogen is evolved, 
 measured at + 10 C. and 742 mm., and what weight of 
 iron oxide is produced ? 
 
 209. Find weight of hydrogen needed to unite with 
 21 g. of oxygen to form water. How much with (a) 
 20ff.;(i)76g.;O)300g.? 
 
 210. How many g. of mercury and how many 1. of 
 chlorine, measured at a temperature of -f- 16 C. when 
 the barometer stands at 770 mm., are consumed in the 
 manufacture of 100 g. of corrosive sublimate? 
 
100 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 211. Find the volume of HF from 71 g. of CaF 2 and 
 enough H 2 SO 4 . 
 
 212. What weight of NH 4 OH is needed to produce 
 131 i. of NH 3 ? 
 
 213. How many g. of CaCO 3 will produce 114 1. of 
 C0 2 ? 
 
 214. How much sodium acetate and caustic soda is 
 needed to yield 300 cc. of CH 4 ? 
 
 215. If 8 g. of methyl alcohol burn in air, what vol- 
 ume of oxygen is used, and what are the weights of the 
 products ? 
 
 216. What weight and volume of chlorine is produced 
 by treating 300 g. of HC1 with enough HNO 3 ? 
 
 217. How many g. of acid calcium carbonate will 
 200 1. of CO 2 with water produce from CaCO 3 ? 
 
 218. What volume of nitrogen, measured at 1 C. 
 and 800 mm., is given off on heating 84 g. ammonium 
 dichromate ? 
 
 219. When 2 g. of sulphur are burned in a closed 
 vessel containing 16 1. of air (21 % O), what volumes 
 of oxygen and sulphur dioxide are present after com- 
 bustion ? 
 
 220. How much calcium will liberate 56 1. of hydro- 
 gen from water? 
 
 221. When 83 g. of cobaltic oxide are heated with 
 HC1, what volume of chlorine is evolved? 
 
 222. A balloon holds 200 Kg. of hydrogen. How 
 much Zn and HC1 are needed? Find volume of hydro- 
 gen at + 90 C. and 760 mm. 
 
 223. A room is 6 m. x 760 cm. x 896 mm. Find the 
 weight of air in the room. 
 
VOLUMES FROM EQUATIONS 101 
 
 224. A room 30 m. x 18 m. x 15 m. is filled with 
 oxygen. What weight of gas does it contain ? 
 
 225. What volume at + 20 C. and under a pressure 
 of two atmospheres will 100 1. of sulphur dioxide, meas- 
 ured at C. and under a pressure of one atmosphere, 
 occupy? What weight of sulphur is necessary to pro- 
 duce this amount of sulphur dioxide? 
 
 226. When 10 g. of turpentine are burned, what 
 volume of carbon dioxide is formed? 
 
 227. How many 1. of hydrogen are obtained on dis- 
 solving 16 g. of magnesium in dilute sulphuric acid ? 
 
 228. How many 1. of hydrochloric acid can be made 
 by the use of 575 g. of KC1? 
 
 229. When 1 g. of HgO and 1 g. KC1O 3 and 1 g. 
 Pb(NO 3 ) 2 are each heated separately and the oxygen is 
 measured, calculate the weight and volume in each case. 
 
 230. How much ozone will 13 g. of oxygen make? 
 What residue and how much will there be ? 
 
 231. How much carborundum will 2 tons of sand 
 make ? What volume of CO will be produced ? (SiO 2 + 
 3 C = SiC + 2CO). 
 
 232. Find the volume of HF which may be produced 
 from 300 g. of CaF 2 at - 6 C. and 791 mm. 
 
 233. If 10 1. of carbon monoxide at + 14 C. and 
 760 mm. are required, what volume o*f carbon dioxide 
 must be passed over red-hot carbon, and what mass of 
 carbon is used? 
 
 234. How many 1. of hydrogen phosphide can be 
 made by the use of 250 g. of calcium phosphide? 
 
 235. How many 1. of hydrogen arsenide can be made 
 with 640 g. of zinc arsenide? 
 
102 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 236. How many 1. of hydrogen and of oxygen are 
 necessary to produce 10 cc. of liquid water? 
 
 237. How many g. of chalk are required to yield 
 15 1. of choke damp? 
 
 238. How many cc. of chlorine at a temperature of 
 + 15 C. and under a pressure of 770 mm. can be ob- 
 tained from 150 g. of silver chloride? 
 
 239. How much cryolite is needed to prepare 100 1. 
 of hydrogen fluoride at + 100 C. and 500 mm.? 
 
 240. When 250 cc. of carbon dioxide are passed over 
 red-hot carbon, what volume of carbon monoxide will 
 be formed? 
 
 241. A room is 25 m. long, 15 m. broad, and 10 m. 
 high ; how much carbon dioxide will it contain at the 
 rate of 4 volumes in 10,000? 
 
 242. What weight in g. of sodium acetate is required 
 to yield 10 1. of methane at + 20 C. and 760 mm. ? 
 
 243. A piece of charcoal is burned in 2 J 1. of oxygen ; 
 how many 1. of carbon dioxide will be formed, and how 
 much will the carbon dioxide weigh? 
 
 244. If I wish to obtain 1 1. of oxygen by heating 
 mercuric oxide, what weight of the oxide shall I need? 
 
 245. What volume of chlorine would exactly decom- 
 pose 25 g. of hydriodic acid ? 
 
 246. What weight of copper and sulphuric acid is 
 needed to yield 3 1. of SO 2 ? 
 
 247. What is the weight of 25 1. of carbon dioxide, 
 and what weight of pure baking soda would be required 
 to prepare it? 
 
 248. Phosphorus is burned in 15 1. of nitrous oxide ; 
 how many 1. of nitrogen will remain? 
 
VOLUMES FROM EQUATIONS 103 
 
 249. What volume of hydrogen, measured over water 
 at + 18 C. and 746.4 mm., will be liberated by the 
 action of aluminum upon 20 g. of sulphuric acid con- 
 taining 41.5 % H 2 SO 4 ? 
 
 250. An unknown volume of hydrogen sulphide re- 
 quired 110.34 cc. of chlorine for complete decomposi- 
 tion. What was the volume of the hydrogen sulphide? 
 
 251. What volume of hydrobromic acid at + 15 C. 
 and 770 mm. pressure would be produced by the action 
 of water upon 50 g. of phosphorus tribromide ? 
 
 252. What volume of oxygen would be required for 
 the complete combustion of 120 g. of bisulphide of 
 carbon? 
 
 253. What volume of oxygen would be required for 
 the combustion of 125 g. of boron? 
 
 254. If 20 g. of a silicate containing 20% of 
 silica are heated with fluorspar and strong sulphuric 
 acid, what volume of silicon fluoride will be produced ? 
 
 255. What weight of materials would be required to 
 prepare 10 1. of chlorine? 
 
 256. How much copper and nitric acid would be re- 
 quired in order to prepare 100 1. of nitric oxide ? 
 
 257. What volume of oxygen at + 120 C. and 
 743 mm. can be obtained by treating an excess of 
 + KMnO 4 with a 1. of sulphuric acid possessing a density 
 of 1.84 at 0C.? 
 
 258. If 3.5 1. of gaseous hydrofluoric acid at + 10 C. 
 and 765 mm. were obtained by heating fluorspar with 
 oil of vitriol, what weight of fluorspar was used? 
 
 259. What volume of oxygen would be required to con- 
 vert 201 g. of phosphorus into (a) P 2 O 3 and (6) P 2 O 5 ? 
 
104 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 260. If 150 g. of iodine are heated with red phos- 
 phorus and water, what volume of hydriodic acid will 
 be produced? 
 
 261. What volume of sulphuretted hydrogen is re- 
 quired for the complete precipitation of a solution 
 containing 5 g. of As 2 O 3 ? 
 
 262. If 20 g. of nitrogen are carried through the 
 following series of reactions, calculate the resulting 
 volume of nitrous oxide at standard conditions : 
 
 3Mg4-N 2 = 
 Mg 3 N 2 + 6 H 2 = 3 Mg(OH) 2 + 2 NH 3 
 
 NH 4 N0 3 = N 2 + 2 H 2 0. 
 
 263. What weight and what volume of hydrogen 
 will be evolved by the action of 15 g. of sodium on 
 water ? What weight of sodium hydrate will be pro- 
 duced? 
 
 264. What volume of sulphuretted hydrogen at 
 + 13 C. and 700 mm. would be produced by boiling 
 15 g. of antimony sulphide with strong hydrochloric 
 acid? 
 
 265. A piece of pure carbon weighing 12.5 g. is 
 lighted and plunged into a jar containing 16 g. of 
 oxygen ; how much carbon, if any, will remain un- 
 burned ? 
 
 266. What volume of hydrogen at 5 C. and 770 
 mm. pressure would be evolved by dissolving 15 g. 
 of pure magnesium in hydrochloric acid? 
 
 267. Calculate the volume of carbon dioxide at 
 + 22 C. and 740 mm. that will be liberated by the 
 action of acid upon 200 g. of calcium carbonate. 
 
VOLUMES FROM EQUATIONS 105 
 
 268. What weight of magnesium will be required 
 for the liberation of 500 cc. of hydrogen at + 20 C. 
 and 740 mm. when acted upon by an acid? 
 
 269. What weight of aluminum will be required for 
 the liberation of 1420 cc. of hydrogen, measured over 
 water at + 18 C. and 746.4 mm., when acted upon by 
 HC1? 
 
 270. Calculate the relative weights of sodium chlo- 
 rate and potassium chlorate necessary to give 20 1. of 
 oxygen at 4 C. and 770 mm. 
 
 271. Calculate the relative weights of potassium 
 chlorate and perchlorate (KC1O 4 ) necessary to give 
 320 1. of oxygen at + 81 C. and 692 mm. 
 
 272. What volume of chlorine, measured at -f- 12 C. 
 and 750 mm. pressure, would be produced by heating 
 50 g. of common salt with sulphuric acid and manga- 
 nese dioxide ? 
 
 273. The iodine in 600 volumes of hydriodic acid is 
 liberated in succession by chlorine and by oxygen. 
 How many volumes of chlorine and how many volumes 
 of oxygen are required ? 
 
 274. A piece of sodium was completely converted 
 into a chloride by the absorption of 200 cc. of chlorine. 
 What was the weight of the sodium ? 
 
 275. How many 1. of sulphuretted hydrogen could 
 be obtained by the action of sulphuric acid upon 329 g. 
 of ferrous sulphide, and what volume of hydrogen 
 would it contain ? 
 
 276. How many 1. of oxygen would be required 
 in order to burn completely 53 1. of sulphuretted 
 hydrogen ? 
 
106 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 277. How many 1. of sulphur dioxide would be pro- 
 duced by burning sulphur in 158 1. of oxygen? 
 
 278. What weight and what volume of sulphur 
 dioxide ought to be obtained by heating 250 g. of 
 copper with sulphuric acid ? 
 
 279. If 60 g. of mercuric oxide are heated, what 
 volume of oxygen at -f- 91 C. and 380 mm. is given 
 off? 
 
 280. What weight of iron would be required to 
 expel 5 1. of hydrogen from hydrochloric acid ? 
 
 281. A gas tank will hold 321 g. of oxygen. What 
 weight and volume of nitrogen and of carbon dioxide 
 will it hold ? 
 
CHAPTER VIII 
 
 Problems in the Combining Volumes of Gases 
 (Gay-Lussac's Law) 
 
 1. If 27 g. of ethylene are completely burned, what 
 is the volume of the products of combustion ? 
 
 2. If 20 1. of hydrogen and 10 1. of chlorine are exposed 
 to sunlight, what are the volumes of the resulting gases? 
 
 3. One 1. of marsh gas is burned. Find weight and 
 volumes of oxygen needed, and of gases produced. 
 
 4. If 100 cc. of dry ammonia gas are decomposed 
 by electricity, what are the weights and volumes of 
 gases formed ? 
 
 5. When 16 g. of CH 4 burn in air, what is the 
 volume of CO 2 produced and weight of water ? 
 
 6. If an electric spark is passed through each of the 
 following gaseous mixtures, calculate what volumes 
 result in each case : 
 
 1st mixture! ? volumes oxygen 
 i 1 volume hydrogen 
 
 -I . , f 2 volumes hydrogen 
 2d mixture 1 J 
 
 1 volume 
 
 -, . . f 1 volume hydrogen 
 3d mixture { % 
 
 I 2 volumes chlorine 
 
 A ,, . . f 1 volume oxygen 
 4th mixture \ * /. c . 
 
 2 volumes chlorine 
 
 107 
 
108 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 7. If 1 volume of carbon monoxide is mixed with 
 1 volume of oxygen and the mixture is exploded in a 
 closed place, what will be the volume of the result- 
 ing gas or mixture at the original temperature and 
 pressure? 
 
 8. How many 1. of oxygen are required in order to 
 burn completely 4 g. of sulphur, and how many 1. of 
 sulphur dioxide will be formed ? 
 
 9. What weight of water will be produced by burn- 
 ing 5 1. of hydrogen ? 
 
 10. What weight of HC1 would result upon burning 
 1 1. of hydrogen in chlorine ? 
 
 11. How many cc. of air are necessary to burn a 
 mixture containing 375 cc. of marsh gas and 450 cc. 
 of olefiant gas (C 2 H 4 ), and how much carbon dioxide 
 and aqueous vapor are produced ? 
 
 12. By the combustion of 1 cc. of sulphuric ether 
 having a sp. gr. of 0.72, how many cc. of carbon dioxide 
 and of aqueous vapor are produced, and how much 
 oxygen is consumed ? 
 
 13. After liberating, by chlorine, the iodine in 
 265 cc. of hydriodic acid, there were 318 cc. of a mix- 
 ture of hydrochloric acid and chlorine. What was the 
 volume of each gas in the mixture ? 
 
 14. How many 1. of air (21 % O) ought to be mixed 
 with 100 volumes of " fire damp" to supply material for 
 the complete combustion of this gas during explosion ? 
 
 15. If 40 g. of ammonia and 40 g. of HBr are 
 brought together, what weight of ammonium bromide 
 results ? What is left over, and what is its volume at 
 + 220 F. and 768 mm.? 
 
COMBINING VOLUMES OF GASES 109 
 
 16. How many 1. of air at 4- 20 C. and 780 mm. are 
 required for the complete combustion of 16 1. of me- 
 thane ; of ethylene ; of acetylene ; of carbon monoxide ; 
 of ammonia; of hydrogen sulphide? 
 
 17. If 1000 g. of bromine are to be united with hy- 
 drogen, what volume of hydrogen is needed at + 450 C. 
 and 766 mm. ? What volume of products results? 
 
 18. If 50 1. of hydrogen and 30 1. of chlorine are 
 mixed and exploded, what volume of hydrogen chloride 
 is produced? What gas and how much remains in 
 excess ? 
 
 19. What volume of hydrochloric acid would result 
 from the complete combination of 50 1. of chlorine with 
 hydrogen, the final temperature and pressure being the 
 same as the initial? 
 
 20. What volume of hydrogen would combine with 
 20 1. of oxygen? How many 1. of water vapor would 
 result? 
 
 21. How many 1. of oxygen will combine with 20 1. 
 of nitric oxide, and what volume of nitrogen peroxide 
 would be formed? 
 
 22. What volume of carbon dioxide will result from 
 the combustion of 27.4 1. of carbon monoxide? 
 
 23. What volume of oxygen is necessary to com- 
 pletely burn 40 1. of the vapor of benzene, and how 
 many 1. of carbon dioxide and water vapor would be 
 formed ? 
 
 24. In a eudiometer 88 cc. of hydrogen and 132 cc. 
 of chlorine are exploded by a spark ; what volume of 
 hydrochloric acid is formed, and what volume of uncom- 
 bined gas will remain? 
 
110 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 25. What volume of oxygen is required to burn 1 1. 
 of the vapor of alcohol to carbon dioxide and water? 
 
 26. What volume of oxygen is required to burn com- 
 pletely 175 cc. of acetylene ? 
 
 27. If ammonia and chlorine react to form nitrogen 
 and hydrochloric acid, what volume of chlorine is re- 
 quired to react completely with 160 1. of ammonia, and 
 what volumes of nitrogen and hydrochloric acid result? 
 
 28. 31. of a mixture in equal volumes of CH 4 , C 2 H 4 , 
 and CO are burned, the products being H 2 O and CO 2 . 
 How much oxygen is required and how much CO 2 is 
 formed ? 
 
 29. If 7 1. of hydrogen are mixed with 8 1. of oxygen 
 and burned so far as possible, what volume of the prod- 
 uct (as a vapor) is formed and what is left uncom- 
 bined ? 
 
 so. What volumes of gases will be left if 3 1. of CH 4 
 and 2 1. of air are caused to unite, so far as possible ? 
 
 31. What volumetric mixture of acetylene and air 
 would be most dangerously explosive ? 
 
 32. Show the relative volumes of the five gases pres- 
 ent when alcohol vapor burns in air. 
 
 33. How many 1. of hydrochloric acid and of oxygen 
 can be made by the use of 875 g. of water? How many 
 1. of chlorine are required ? 
 
 34. How many 1. of air are necessary to burn 150 g. 
 of benzol? Composition of air is oxygen 20.96% and 
 nitrogen 79.04%. 
 
 35. When 30 1. of hydrogen were mixed with 18 1. 
 of oxygen and chemical union was produced, how much 
 aqueous vapor having a temperature of + 140 C. and 
 
COMBINING VOLUMES OF GASES 111 
 
 760mm. was obtained? Which gas remained in excess, 
 and what was its volume at the temperature and pres- 
 sure given above ? 
 
 36. How many 1. of oxygen would be required to 
 burn 101. of H 2 S? 
 
 37. How many 1. of oxygen will combine with 10 1. 
 of nitric oxide, and what volume of nitrogen peroxide 
 will be formed ? 
 
 38. If nitrogen and hydrogen could be made to com- 
 bine completely, what volume of each would be required 
 to form 10 1. of gaseous ammonia? 
 
 39. What volume of hydrogen and of oxygen at 
 -f 100 C. would combine to form 1 1. of steam? 
 
 40. If 1000 1. of ammonia gas are decomposed, what 
 volume of nitrogen and of hydrogen result if measured 
 at -10C. and 600mm.? 
 
 41. If 30 cc. of hydrogen are mixed with 40 cc. of 
 air that contains 20 % of oxygen, and the mixture is 
 ignited, what gases remain after explosion and what 
 is the volume of each? 
 
 42. A mixture of 10 cc. of hydrogen and 10 cc. of 
 chlorine, exploded by an electric spark, yields 20 cc. of 
 hydrogen chloride. Show how this indicates that the 
 molecule of hydrogen consists of at least two atoms. 
 
 43. If 2 volumes of ethylene weighing 28 g. are 
 burned in air, what volumes of nitrogen and of other 
 gases result? 
 
 44. After 72 cc. of NH 3 are decomposed by electri- 
 city, 100 cc. of oxygen are introduced and the mixture 
 is exploded; what gases remain and how much of 
 each ? 
 
112 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 45. One Kg. of carbon disulphide is burned in oxygen. 
 What weight of oxygen is needed, and what is the volume 
 of each of the products formed at + 20 C. and 760 mm.? 
 
 46. When 150 cc. of oxygen are mixed with 400 cc. 
 of hydrogen and the mixture is exploded, what volume 
 of steam is produced? Which gas, and how much of 
 it, remains uncombined? 
 
 47. If 50 cc. of hydrogen are exploded with 75 cc. of 
 oxygen, what is the total volume of the gases after the 
 explosion, measured at -f 150 C. and 760mm. pressure? 
 
 48. When 40 1. of CO are burned, what is the volume 
 of CO 2 produced? 
 
 49. What volumes of the components would yield 
 100 g. of nitrogen tetroxide ? 
 
 50. If 500 cc. of oxygen are exploded with 250 cc. 
 of hydrogen, what gas, if any, will remain and how much 
 of it? 
 
 51. How much oxygen will be required for the com- 
 plete combustion of 10 g. of stibine and arsine, re- 
 spectively ? 
 
 52. How many 1. of oxygen are contained in 3 1. of 
 nitrogen tetroxide? 
 
 53. If 20 g. of MnO 2 are boiled with an excess of 
 hydrochloric acid until all the MnO 2 is decomposed, 
 and the resultant chlorine is united with hydrogen, 
 what volume of H is needed, and what volume of HC1 
 results if both are measured at + 45 C. and 746 mm. ? 
 
 54. What volume of oxygen is required for the com- 
 bustion of 575 cc. of AsH 3 ? 
 
 55. How many cc. of hydrogen and nitrogen are con- 
 tained in a 1. of ammonia gas ? 
 
COMBINING VOLUMES OF GASES 113 
 
 56. If 100 volumes of air containing 21 volumes of 
 oxygen are mixed with 70 volumes of hydrogen, and an 
 electric spark is passed through the mixture, what will 
 be the volume of the gas remaining and of what will it 
 consist ? 
 
 57. If 50 cc. of hydrogen are exploded with 45 cc. of 
 oxygen, what is the total volume of the gases after the 
 explosion, measured at -f- 150 C. and 760 mm. pressure? 
 
 58. How many cc. of hydrogen and nitrogen are 
 contained in 1 m. 3 of ammonia gas? 
 
 59. How many 1. of hydrogen can be obtained from 
 61. of HC1? 
 
 60. One ft. 3 of hydriodic acid is decomposed by an 
 excess of bromine. How many ft. 3 of hydrobrornic 
 acid are formed? 
 
 61. What volume of oxygen is required for the com- 
 plete combustion of 101 g. of SbH 3 ? 
 
 62. If 50 cc. of air are mixed with 25 cc. of hydro- 
 gen and exploded in a eudiometer, what volume will 
 the remaining gas occupy and of what will it consist? 
 
 63. What weight of oxygen is required for the com- 
 plete combustion of 24 1. of phosphine, measured at 
 + 15 C. and 740 mm. pressure? 
 
 64. An unknown volume of hydrogen sulphide re- 
 quired 157 cc. of oxygen for complete decomposition. 
 What was the volume of the hydrogen sulphide? 
 
 65. A mixture of 300 cc. of methane and 150 cc. of 
 oxygen was exploded. What was the volume of the 
 product after the removal of aqueous vapor (by absorp- 
 tion), temperature being + 100 C. and pressure 760mm. 
 constant throughout? 
 
114 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 66. A mixture of 250 cc. of carbon monoxide and 
 120 cc. of oxygen was exploded. Calculate the volume 
 of gaseous product. 
 
 67. A mixture of 420 cc. of hydrogen and 180 cc. of 
 oxygen was exploded. What was the volume of prod- 
 uct after the removal of aqueous vapor (by absorption 
 with phosphorus pentoxide), temperature being -f 100 
 C. and pressure of 760mm.? 
 
 68. If 17 1. of NH 3 are decomposed, how many 1. 
 will there be of resultant gases ? 
 
 69. A mixture of 200 cc. of carbon monoxide and 
 300 cc. of oxygen was exploded over mercury. Cal- 
 culate the volume of product, at + 27 C. and pressure 
 of 740 mm. constant throughout. 
 
 70. A mixture of oxygen and hydrogen measuring 
 250 cc. was exploded. The volume of product meas- 
 ured 76.47 cc., at +17 C. and pressure of 754.4 mm. 
 Calculate the volumes of hydrogen and oxygen. 
 
 71. A mixture of 320 cc. of carbon monoxide and 
 1800 cc. of oxygen was exploded. Calculate the 
 volume of gaseous product after the removal of the 
 carbon dioxide (absorption by lime). 
 
 72. A mixture of 80 cc. of methane and 200 cc. of 
 oxygen was exploded over mercury. Calculate the 
 volume of product, at temperature of + 20 C. and 
 barometric pressure of 757.4 mm. constant. 
 
 73. A mixture of 490 cc. of hydrogen and 1300 cc. 
 of oxygen was exploded. . Calculate the volume of 
 product, at temperature of -}- 25 C. and pressure 
 753.6 mm. constant. 
 
i 
 
 COMBINING VOLUMES OF GASES 115 
 
 74. When 250 cc. of dry air were mixed with 150 cc. 
 of hydrogen and exploded, the volume of product was 
 350 cc. Calculate the percentage of oxygen in the 
 sample of air. Temperature of -f 100 C. and atmos- 
 pheric pressure remained constant. 
 
 75. A mixture of hydrogen sulphide with an excess 
 of oxygen measured 350 cc. at + 160 C. and 750 mm. 
 pressure. \ After explosion (with complete combustion), 
 the volume of dry gaseous product read 260 cc. at 
 these same conditions. Calculate the volume of hydro- 
 gen sulphide in the mixture. 
 
 76. Find the proportions by weight and by volume 
 in which ethane will combine with oxygen. 
 
 77. A volume of nitric oxide, measuring 400 cc., was 
 required for the combustion of a definite weight of 
 phosphorus. What volume of nitrogen remained free? 
 
 78. What volume of water gas is theoretically possible 
 from the action of 1 1. of steam upon heated coke ? 
 
 79. In the decomposition of methane by chlorine, 
 what volume of hydrogen chloride corresponds to 1 vol- 
 ume of methane ? 
 
 80. A mixture of 400 cc. of methane and 1000 cc. 
 of chlorine was exploded. Calculate the volume of 
 gaseous product. 
 
 81. How many 1. of air are required for the com- 
 plete combustion of 10 1. of (ft) marsh gas ; (6) olefiant 
 gas ; (c) acetylene ? 
 
 82. If 5 1. of chlorine are mixed with 5 1. of carbon 
 monoxide, what volume of phosgene gas is produced, 
 and how much hydrochloric acid and carbon dioxide 
 would be produced by the decomposition of this gas 
 with water ? 
 
116 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 83. If 5 1. of carbon monoxide are burned, what 
 volume of oxygen will be used, and what volume of 
 carbon dioxide will be formed ? 
 
 84. If an electric spark is passed through a mixture 
 of 5 volumes of carbon monoxide and 3 volumes of 
 oxygen, what diminution in bulk will be observed ? 
 
 85. If 50 cc. of carbon monoxide are mixed with 
 20 cc. of oxygen and exploded, and the resulting 
 mixture is then shaken up with sodium hydrate, what 
 volume of gas will remain and what gas will it be ? 
 
 86. Carbon is burned in 220 1. of oxygen; what 
 volume of carbon dioxide will be formed ? 
 
 87. If 50 cc. of nitrous oxide are decomposed into 
 nitrogen and oxygen, how many cc. of each will be 
 formed ? 
 
 88. A mixture of acetylene with an excess of oxygen 
 measured 350 cc. at + 25 C. and 745 mm. pressure. 
 After explosion the volume of dry gaseous product read 
 275 cc. under the same conditions. Calculate the volume 
 of acetylene in the mixture. 
 
 89. A mixture of acetylene with an excess of oxygen 
 measured 240 cc. at + 24 C. and 752.4 mm. pressure. 
 After explosion the volume of product read 221.8 cc. 
 at -f 28 C. and 750.1 mm. pressure. Calculate the 
 volume of acetylene in the mixture. 
 
 90. If 600 volumes of carbon monoxide are mixed 
 with 600 volumes of oxygen, an electric spark is passed 
 through the mixture, and then a solution of caustic 
 potash is added, what volume of gas will be ab- 
 sorbed and of what will the residue, if there is any, 
 consist? 
 
COMBINING VOLUMES OF GASES 117 
 
 91. How many volumes of oxygen are required for 
 the complete combustion of 1 1. of each of the following : 
 (a) CO; (6) CH 4 ; < C 2 H 4 ; (d) C 2 H 2 ; < H 2 S ; 
 
 92. If 500 cc. of hydrogen at + 39 C. are exploded 
 with 500 cc. of oxygen under a pressure of 332.5 mm., 
 what volume of which gas is left ? 
 
 93. How many 1. of oxygen will be required to burn 
 50 1. of C 2 H 4 and how many of CO 2 will form ? 
 
 94. If 10 ft. 3 of H 2 S are burned, what volume of each 
 product will be formed ? 
 
 95. I have 5500 cc. of CO 2 formed by the combustion 
 of CO in air. How much air was required and how 
 much CO ? 
 
 96. State the volume of the products resulting from 
 the combustion of 2.5 1. of carbon disulphide gas. 
 
 97. What volume of products results from the de- 
 composition of 100 1. of ammonia ? 
 
 98. One million molecules of hydrogen will unite 
 with how many molecules of oxygen to form how many 
 molecules of water ? What will be the relative weights 
 of hydrogen and water ? 
 
 99. A mixture of 10 cc. of chlorine and 10 cc. of 
 hydrogen, exploded by an electric spark, yields 20 cc. 
 of hydrogen chloride. Show how this indicates that 
 the molecule of hydrogen consists of at least 2 atoms. 
 
CHAPTER IX 
 
 Calculation of Formulas 
 
 1. A compound has the following percentage com- 
 position : carbon, 37.61% ; hydrogen, 12.53% ; oxy- 
 gen, 49.86%. One 1. of its vapor weighs 1.4339 g., 
 What is its formula ? 
 
 2. A gas has the following composition : carbon, 
 27.39%; oxygen, 72.60%. Its density (air) is 1.52. 
 What is its formula ? 
 
 3. What is the simplest formula of a substance 
 which consists of oxygen, 88.83%, and hydrogen, 
 H.11%? 
 
 4. Calculate the simplest formula of mercuric oxide, 
 which contains 92.59 % of mercury and 7.41 % of oxygen. 
 
 5. What is the simplest formula of a substance 
 consisting of calcium, 29.49% ; sulphur, 23.59% ; and 
 oxygen, 46.92%? 
 
 6. The percentage composition of a mineral is found 
 to be: calcium, 40.12% ; carbon, 12.04%; and oxy- 
 gen, 47.84%. What is its simplest formula? 
 
 7. Acetic acid consists of carbon, 40 % ; hydrogen, 
 6.67%; and oxygen, 53.33%. Its vapor density is 
 30. What is its molecular formula ? 
 
 8. What is the molecular formula of the gas having 
 the composition : nitrogen, 30.43 % : oxygen, 69.57 % ? 
 The weight of 1 1. is 2.061 g. 
 
 118 
 
CALCULATION OF FORMULAS 119 
 
 9. What is the molecular formula of the gas having 
 the density 197 and the composition: iodine, 96.70%; 
 carbon, 3.05% ; hydrogen, 0.25%? 
 
 10. In 100 parts of a compound of manganese and 
 oxygen there are 63.22 parts of manganese and 36.78 
 parts of oxygen. What is the simplest formula possi- 
 ble? 
 
 11. Calculate the formulas of the following : 
 
 Ba = 58.80 K = 31.91 Ca = 40.00 Ag = 75.27 
 8 = 13.75 01 = 28.94 = 12.00 01 = 24.73 
 O = 27.45 O = 39.15 O = 48.00 
 
 12. 
 
 
 
 
 K = 38.68 
 
 N = 13.89 
 
 Mg = 21.65 
 P = 27.92 
 
 K = 16.00 
 Pt = 40.41 
 
 Na=18.54 
 8 = 25.84 
 
 0=47.43 
 
 O = 50.43 
 
 01 = 43.59 
 
 H= 0.81 
 
 
 
 
 = 25.79 
 
 H 2 O = 29.02 
 
 13. 
 
 Na = 18.54 CaO= 9.20 Fe = 72.41 
 
 8 = 25. 84 A1 2 O 3 = 16.85 O = 27. 59 
 
 H= 4.03 Si0 2 = 59.29 Mn = 71.69 
 
 O = 51.59 H 2 O = 14.66 O = 28.31 
 
 14. 
 
 Cu = 34.46 CaO = 43.45 Ag = 53.15 Lithia = 6.43 
 
 Fe = 30.59 A1 2 O 3 = 17.68 Cu = 31.08 Alumina = 29.26 
 
 8 = 34.95 SiO 2 = 38.87 8 = 15.77 Silica = 64.31 
 
 15. 
 
 
 
 
 Pb = 76.36 
 
 = 21.03 
 
 = 52.17 
 
 K = 42.41 
 
 P= 6.86 
 
 H= 2.63 
 
 H = 13.04 
 
 Fe = 15.22 
 
 01= 2.62 
 
 K = 34.27 
 
 O = 34.79 
 
 = 19.56 
 
 O = 14.16 
 
 O = 14.03 
 
 
 N = 22.81 
 
 
 8 = 28.04 
 
 
 
120 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 16. 
 
 = 90.57 = 89.55 = 79.73 Si = 19.50 
 
 H = 9.43 H = 10.45 H= 6.32 = 66.62 
 
 N= 13.95 H = 13.88 
 
 17. 
 
 = 75.46 H = 6.59 N = 8.38 O = 9.57 
 
 18. Find the formula of that nitrate which gave, by 
 analysis, 62.45% lead, 8.68% nitrogen, and 28.85% 
 oxygen. 
 
 19. Derive the formula of that substance which gave, 
 by analysis, 52.02% carbon, 13.20% hydrogen, and 
 34.68% oxygen. 
 
 20. What is the formula of that acetate which gave, 
 by analysis, 63.61 % lead, 14.62 % carbon, 1.98 % hydro- 
 gen, and 19.79% oxygen? 
 
 21. An oxide of iron gave, by analysis, 69.80 % iron ; 
 what is the formula? 
 
 22. An oxide of barium gave, by analysis, 81 % 
 barium ; what is the formula? 
 
 23. The vapor density of a gas is 13.91. The analy- 
 sis gives the following composition: = 85.62 and 
 H = 14.38. What is the formula? Find the weight 
 of 11. 
 
 24. Derive the formula of the oxide produced when 
 6.87 g. of barium unite with 1.6 g. of oxygen. 
 
 25. Find the formula of the oxide formed in the 
 combustion of 2.61 g. of aluminum with oxygen to a 
 final weight of 5.01 g. 
 
 26. What is the formula of the oxide produced by the 
 combustion of 43.45 g. of lead with 4.48 g. of oxygen? 
 
CALCULATION OF FORMULAS 121 
 
 27. Derive the formula of the oxide produced by the 
 burning of 2.5 g. of phosphorus in oxygen to a final 
 weight of 5.7 g. 
 
 28. Calculate the formulas of : 
 
 00 (*) 
 
 N = 22.05 Si0 2 = 23.53 
 
 C = 14.18 CaO= 1.90 
 
 O = 56.68 A1 2 O 3 = 37.72 
 
 H= 7.09 Water = 36.85 
 
 29. What will be the formula of a hydrocarbon that 
 contains twice as many hydrogen atoms as carbon, and 
 the vapor of which has a density of 1.947? 
 
 30. Find the simplest formula for acid potassic car- 
 bonate, its percentage composition being : hydrogen, 
 1.00; potassium, 39.06; carbon, 11.99; oxygen, 47.95. 
 
 31. In 100 parts of crystallized ferrous sulphate there 
 are 20.15 parts of iron, 11.51 parts of sulphur, 23.02 
 parts of oxygen, and 45.32 parts of water; what is its 
 simplest formula? 
 
 32. What is the simplest formula of morphia, its 
 percentage composition being: carbon, 71.58; hydrogen, 
 6.66; nitrogen, 4.91; oxygen, 16.85? 
 
 33. Derive the formula of crystallized sodium sul- 
 phate, 8.16 g. of which lost 4.51 g. of water upon 
 dehydration. 
 
 34. Find the formula of crystallized copper sulphate, 
 7.84 g. of which lost 2.79 g. of water upon heating. 
 
 35. Calculate the formula of crystallized aluminum 
 sulphate, 9.54 g. of which lost 4.61. g. of water upon 
 heating. 
 
122 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 36. Work out the formula of aluminum hydroxide, 
 4.75 g. of which lost 1.64 g. of water and left a residue 
 of AL0 3 . 
 
 L 6 
 
 Deduce the formulas of the following substances : 
 
 37. Magnesium, 9.76; sulphur, 13.01; oxygen, 
 26.01; water, 51.22. 
 
 38. Zinc, 22.70; sulphur, 11.15; oxygen, 22.28; 
 water, 43.87. 
 
 39. Sodium, 32.79; aluminum, 13.02; fluorine, 54.19. 
 
 40. Aluminum, 16 ; sulphur, 28 ; oxygen, 56. 
 
 41. Copper, 57.46; carbon, 5.43; hydrogen, 0.91; 
 oxygen, 36.20. 
 
 42. Hydrogen, 3.18; oxygen, 33.88; nitrogen, 14.84; 
 sulphur, 16.95; nickel, 31.15. 
 
 43. Carbon, 19.04; hydrogen, 4.76 ; sulphur, 25.40; 
 oxygen, 50.80. 
 
 44. Carbon, 46.66; hydrogen, 4.26; nitrogen, 5.20; 
 oxygen, 5.92; platinum, 18.26 ; chlorine, 19.70. 
 
 45. Calculate the formula of the nitrate, 19.7 g. of 
 which were prepared from 10.4 g. of bismuth. 
 
 46. Find the formula of that chlorate, 4.165 g. of 
 which lost 1.3 g. of oxygen upon heating and gave a 
 residue of barium chloride. 
 
 47. What is the formula of mercuric cyanide, 5.4 g. 
 of which lost 1.1 g. of cyanogen upon heating? 
 
 48. Derive the formula of the double salt of ammo- 
 nium sulphate and copper sulphate, 4.12 g. of which 
 lost 1.81 g. of ammonium sulphate upon heating. 
 
 49. The vapor density of steam is 9. The percent- 
 age composition of water is : hydrogen, 11.11 ; oxygen, 
 88.89. What is the formula of water ? 
 
CALCULATION OF FORMULAS 123 
 
 50. The vapor density of alcohol vapor is 23. In 
 100 parts there are 52.18 parts of carbon, 13.04 parts 
 of hydrogen, and 34.78 parts of oxygen. What is the 
 formula of alcohol ? 
 
 51. The vapor density of the vapor of ethylene chloride 
 is 49.5, and its percentage composition is: carbon, 24.24; 
 hydrogen, 4.04 ; chlorine, 71.72. What is its formula? 
 
 52. The vapor density of a certain gas is 13.91, or the 
 weight of a 1. of this gas at C. and 760 mm. pressure 
 is 1.26 g. (Use only one of these weight relations.) The 
 analysis of this gas gave the following percentages: 
 carbon, 85.62; hydrogen, 14.38. What is the formula? 
 
 53. Analysis of a compound gave : lead, 68. 30 % '> 
 sulphur, 10.55%; oxygen, 21.15%. Calculate the em- 
 pirical formula. 
 
 54. Calculate the empirical formulas from the follow- 
 ing analytical results : potassium, 52.45 % ; chlorine, 
 47.55 % - Arsenic, 41.32 % ; chlorine, 58.66 % . Sodium, 
 32.43%; hydrogen, 0.71%; phosphorus, 21.82%; 
 oxygen, 45.04 %. Potassium, 35.56 % ; iron, 17.00 % ; 
 cyanogen, 47.44 % . Magnesium, 21. 82 % ; phosphorus, 
 27.86% ; oxygen, 50.32%. 
 
 55. Aldehyde has the following composition : C, 
 54.67%; H, 9.11%; and O, 36.22%. The density 
 (air) of its vapor is 1.526. What is its formula? 
 
 56. Butyric acid has the same percentage composi- 
 tion as an aldehyde, but the density (air) of its vapor 
 is 3.052. What is its formula ? 
 
 57. Analysis of a compound gives 26.67 % C, 2.22 % 
 H, and 71.11 % O ; what is its simplest formula ? If that 
 is the correct one, what should be the vapor density of 
 the gas ? 
 
124 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 58. A compound consists of 5.88 % H and 94.12 % O ; 
 find the smallest formula that can apply to it. 
 
 59. An ore of iron analyzes 70 % Fe and 30 % O : 
 what formula should it have ? 
 
 60. Zinc is obtained from its sulphide, a specimen of 
 which contains 67.01% Zn and 32.99% S. Ascertain 
 the formula of zinc sulphide. 
 
 61. Find the formula of a hydrocarbon that contains 
 an equal number of hydrogen and carbon atoms, and 
 the vapor of which has a density (air) of 0.9. 
 
 62. Formic acid has the composition: C, 26.21%; 
 O, 69.43% ; and H, 4.36%. The density (air) of its 
 vapor is the same as that of alcohol. Find the formula. 
 
 63. Find the formulas of the following two substances : 
 
 00 (0 
 
 Bi = 42.99 K= 8.24 
 
 O = 29.74 Al= 5.69 
 
 N= 8.67 8 = 13.50 
 
 Water = 18.60 O = 27.01 
 
 Water = 45. 56 
 
 64. Oxalic acid consists of C, 26.79%; H, 2.23%; 
 and O, 70.98 %. Find the formula. 
 
 65. Alcohol is C, 52.28; O, 34.64; and H, 13.08. 
 Calculate the formula. 
 
 66. Deduce the formulas of the following : 
 
 00 (*) 
 
 Fe = 20.15 K= 7.77 
 
 8 = 11.51 Mn = 10.95 
 
 O = 24.02 8 = 12.75 
 
 Water = 44. 32 O = 25.48 
 
 Water = 43. 05 
 
CALCULATION OF FORMULAS 125 
 
 67. Red lead consists of Pb, 90.65 % ; and O, 9.35 %. 
 What is the formula ? 
 
 68. The sp.gr. of mercurous chloride is 7. It con- 
 tains 84.92 % of Hg and 15.08 % of chlorine. To what 
 formula would this correspond ? 
 
 69. Calculate the formula of the following : 
 
 Na = 14.41 Sb = 25.05 8 = 26.72 Water = 33.82 
 
 70. Calculate the formulas from the following per 
 cents: calcium, 38.72; phosphorus, 20.00; oxygen, 
 41.28. 
 
 71. Potassium, 28.73; hydrogen, 0.73; sulphur, 
 23.52; oxygen, 47.02. 
 
 72. Potassium, 45.95; nitrogen, 16.45; oxygen, 
 37.60. 
 
 73. Aluminum, 16 ; sulphur, 28 ; oxygen, 56. 
 
 74. Carbon, 85.71; hydrogen, 14.29. 
 
 75. Carbon, 92.3; hydrogen, 7.7. 
 
 76. One volume of a gaseous hydrocarbon at 
 -f 100 C. yields on combustion double its volume of 
 CO 2 and 3 times its volume of steam at the same tem- 
 perature. Find the formula of the gas. 
 
 77. A compound has the following composition : 
 phosphorus, 20.22%; oxygen, 10.43%; chlorine, 
 69.35%. The density (air) of its vapor is 5.295. 
 What is its formula? 
 
 78. If an iron ammonium sulphate contains \ of its 
 weight in iron, find the formula. 
 
 79. A compound has the following composition : 
 phosphorus, 22.58% ; chlorine, 77.42%. One 1. of the 
 vapor weighs 6.13 g. Calculate the formula. 
 
126 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 80. Calculate the formulas of the substances pos- 
 sessing the following percentage compositions : 
 Magnesium = 25.57 Sodium =32.43 Potassium = 26.585 
 
 Chlorine = 74.43 Sulphur = 22.55 Chromium = 35.390 
 Oxygen = 45.02 Oxygen = 38.025 
 
 81. Find the formula when Zn = 22.67; S = 11.15; 
 O = 22.29; and water = 43. 89. 
 
 82. Calculate the formula when Zn = 54.14; 
 Si = 11.67 ; O = 26.67 ; and water = 7.52. 
 
 83. Assign formulas to the following : 
 
 00 0) 
 
 CO = 22. 74 A1 2 O 3 = 16.86 
 
 N = 26.96 CaO= 9.20 
 
 Cl = 41.05 SiO 2 = 59.28 
 
 H= 5.78 Water = 14. 66 
 
 Water = 3.47 
 
 84. Calculate the formulas from the following per 
 cents: carbon, 19.04; hydrogen, 4.76; sulphur, 
 25.40; oxygen, 50.80. 
 
 85. Carbon, 74.07; hydrogen, 8.64; nitrogen, 17.29. 
 
 86. Carbon, 46.66 ; hydrogen, 4.26; nitrogen, 5.20; 
 oxygen, 5.92; platinum, 18.26; chlorine, 19.70. 
 
 87. Lime, 28.4; magnesia, 12.3; iron monoxide, 
 12.3; manganese monoxide, 1.9; carbon dioxide, 44.4. 
 
 88. A mineral gave the following numbers on analysis : 
 SiO 2 , 46.96; MgO, 31.26; H 2 O, 21.22. Calculate its 
 formula. 
 
 89. A specimen of cobalt bloom was found to have 
 the following composition: As 2 O 5 , 38.43; CoO, 36.52 ; 
 FeO, 1.01; H 2 O, 24.14. Determine its formula. 
 
CALCULATION OF FORMULAS 127 
 
 90. One hundred OG. of ammonia gas are completely 
 decomposed by a series of electric sparks, yielding 
 200 cc. of mixed hydrogen and nitrogen. An excess 
 of oxygen is next added, when the volume of mixed 
 gases is found to amount to 290 cc. The mixture is 
 now exploded, when 65 cc. of gas remain. Show from 
 these data that the formula for ammonia is NH 3 . 
 
 91. Ca = 40; C = 12; O = 48. Calculate the 
 simplest formula. Find the percentage composition 
 of C in this formula to see if your answer is correct. 
 
 92. Calculate the molecular formula of a substance 
 having the following composition: carbon, 74.1%; 
 hydrogen, 8.6 % I nitrogen, 17.3 %. The vapor density 
 is 81. 
 
 93. C = 10.04%; H = 0.83%; Cl = 89.13%; and 
 the vapor density is 59.75. Find the formula. 
 
 94. On analysis, 18 g. of a compound of iron and 
 sulphur yielded 8.4 g. of iron and 9.6 g. of sulphur; 
 what is its simplest formula ? 
 
 95. On analysis, 48 g. of a compound yielded 37.21 g. 
 of lead, 2.16 g. of carbon, and 8.63 g. of oxygen; what 
 is its simplest formula? 
 
 96. What is the simplest formula of a substance, 
 27 g. of which, on analysis, yielded 2.64 g. of magne- 
 sium, 3.51 g. of sulphur, 7.02 g. of oxygen, and 
 13.83 g. of water? 
 
 97. A compound of arsenic and oxygen is composed of 
 75 + %As, 24+% O; what is its smallest formula? Its 
 vapor density being 198, what should be its true formula? 
 
 98. A compound of hydrogen and carbon has 92.3% 
 C and 7.7 % H. Find its smallest formula. The density 
 being 13, what is the proper formula? 
 
128 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 99. An analysis of a salt gave the following per- 
 centage numbers: S, 22.53; Na, 32.39; O, 45.08. 
 What is its empirical formula? 
 
 100. A salt on analysis gives the following percent- 
 age numbers: N, 9.09; O, 20.77; Ag, 70.13. Calcu- 
 late the simplest formula for this body. 
 
 101. Calculate the formula for a body which has the 
 following percentage composition: oxygen, 38.1; hy- 
 drogen, 0.8; phosphorus, 24.6 ; sodium, 36.5. 
 
 102. Calculate the formula of a body which has the 
 following percentage composition: magnesium, 3.98; 
 calcium, 13.28; potassium, 12.99; sulphuric acid 
 (SO 4 ), 63.77; water, 5.98. 
 
 103. Find the formula of the following : O, 48 % ; 
 S, 24%; andFe, 28%. 
 
 104. A substance contains carbon, 20 % ; oxygen, 
 26.6%; and sulphur, 53.3%. Find its formula. 
 
 105. Find the formulas of the following minerals : 
 
 00 (ft) 
 
 SiO 2 = 65.69 N 2 O = 4.21 
 
 A1 2 O 3 = 17.97 CaO = 12.93 
 
 CaO= 1.34 A1 2 O 3 = 30.68 
 
 N 2 0= 1.01 Si0 2 = 39.99 
 
 K 2 = 13.99 H 2 = 12.19 
 
 106. Calculate the formulas : 
 
 00 (ft) 
 
 A1 2 O 3 = 58.66 SiO 2 = 47.24 
 
 SiO 2 = 34.20 MnO 2 = 31.50 
 
 F= 7.14 Water =21. 26 
 
CHAPTER X 
 
 Atomic and Molecular Weight Calculations 
 
 1. Ten 1. of a gas weigh 17.92 g. ; find its molecular 
 weight. 
 
 2. The sp. gr. of hydrogen iodide is 4.4; calculate 
 its molecular weight. 
 
 3. Find the molecular weight of the gas of which 
 20 g. occupy 9.9 1. under 1.5 atmospheres pressure at 
 + 17C. 
 
 4. One hundred g. of lead form 146.45 g. of lead 
 sulphate; find the molecular weight of sulphuric acid. 
 
 5. The vapor of a compound is found to be thirty- 
 nine times as heavy as hydrogen at the same tempera- 
 ture and pressure. What is the molecular weight of 
 the compound? 
 
 6. A 1. of nitrous oxide weighs 1.97 g. ; find its 
 molecular weight. 
 
 7. Find the molecular weight of the gas the density 
 of which is 1.524. 
 
 8. A 1. of ammonia, under standard conditions, 
 weighs 0.76 g. ; find its molecular weight. 
 
 9. A 1. of nitrous oxide, under standard conditions, 
 weighs 1.97 g. ; find its molecular weight. 
 
 10. A 1. of cyanogen, under standard conditions, 
 weighs 2.33 g. ; find its molecular weight. 
 
 129 
 
130 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 11. A 1. of ethane, under standard conditions, weighs 
 1.34 g. ; find its molecular weight. 
 
 12. Find the molecular weight of the gas the density 
 of which is 1.108. 
 
 13. A 1. of arsine weighs 3.49 g. under standard 
 conditions ; find its molecular weight. 
 
 14. Find the molecular weight of the gas the density 
 of which is 0.623. 
 
 15. Calculate the molecular weights of the following 
 gases : 
 
 one 1. of ethane weighs 1.34 g. ; 
 
 one 1. of hydrogen sulphide weighs 1.52 g.; 
 
 one 1. of nitric oxide weighs 1.34 g.; 
 
 one 1. of phosphine weighs 1.52 g. ; 
 
 one 1. of carbonyl chloride weighs 4.42 g. ; 
 
 one 1. of SiF 4 weighs 4.68 g. ; 
 
 one 1. of butane weighs 2.59 g. 
 
 16. The weight of 3840 cc. of a certain vapor, at 
 standard conditions, is 24 g. ; what is the molecular 
 weight of the substance ? 
 
 17. If 3180 cc. of a gas, measured at + 24 C. and 750.2 
 mm. pressure, weighed 6 g., what is the molecular weight? 
 
 18. The vapor density of a gas is 44 ; find its mo- 
 lecular weight, sp. gr., and the weight of 1 1. 
 
 19. Calculate the molecular weights of the following 
 gases: 
 
 the density (referred to air) of ammonia is 0.59; 
 
 the density (referred to air) of HF is 0.69; 
 
 the density (referred to air) of methyl alcohol is 1.11 ; 
 the density (referred to air) of mercury vapor is 6.91; 
 the density (referred to air) of HI is 4.42. 
 
ATOMIC AND MOLECULAR WEIGHTS 131 
 
 20. Find the molecular weights of the following 
 bodies: (air = l) 
 cadmium at + 940 C., relative density = 3.94 ; 
 phosphorus at + 500 C., relative density = 4.35 ; 
 mercury at + 446 C., relative density = 6.98. 
 
 21. Determine the molecular weights of the follow- 
 ing gases from the data annexed: nitrogen; 2 1. weigh 
 2.51 g. 
 
 22. Carbon monoxide; 1500 cc. weigh 1.88 g. 
 
 23. Carbon dioxide ; 500 cc. weigh 0.98 g. 
 
 24. One 1. of SO 2 weighs 2.86 g. ; what is its molec- 
 ular weight? 
 
 25. The weight of 1| 1. of CO is 1.88 g.; calculate 
 the molecular weight. 
 
 26. What is the molecular weight of marsh gas, 3 1. of 
 which weigh 2.15 g.? 
 
 27. Sulphur dioxide is 2.22 times as heavy as air; 
 find its density and molecular weight. 
 
 28. If 30 g. of a gas occupy 52.7 1. under 0.5 atmos- 
 pheric pressure at -f 27 C., what is the molecular weight 
 of the gas? 
 
 29. A quantity of gas measuring 5.4 1., when the 
 temperature is + 15 C. and pressure 740 mm., weighs 
 7.6 g. ; what is its molecular weight? 
 
 30. The vapor density of a gas was 31.17 when its 
 temperature was + 11 C. and under a pressure of 750 
 mm.; what is its molecular weight? 
 
 31. Calculate the molecular weights of the following 
 gases from their vapor densities: (a) chlorine, 35.5; 
 (5) hydrochloric acid, 18.25; (e) ammonia, 8.5; 
 nitrogen, 14; (e) steam, 9. 
 
132 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 32. Berzelius found that 4.20775 parts of MnCl 2 
 yielded 9.575 parts of AgCl ; what is the atomic weight 
 of silver? 
 
 33. By analysis we find that for every 100 parts of 
 silver bromide there are 57.44 parts of Ag and 42.56 
 parts of Br. The atomic weight of Br = 79.8. What 
 is the atomic weight of silver? 
 
 34. We find from analysis that barium chloride con- 
 tains 65.86% of Ba and 34.14% of Cl. There are no 
 compounds of Ba the vapor density of which has been 
 determined. The specific heat of Ba being unknown, 
 how would you determine the atomic weight of Ba? 
 
 35. Marignac found that 3.8844 g. NaCl were re- 
 quired for the precipitation of 11.308 g. of AgNO 3 ; 
 find atomic weight of nitrogen. 
 
 36. By heating 15 g. of pure silver in a stream of 
 chlorine, 19.9306 g. of silver chloride are produced. 
 The weight of the atoms of silver in a molecule of silver 
 chloride is 108. What is the molecular weight of sil- 
 ver chloride and the number of atoms of chloride in a 
 molecule? 
 
 37. If 3.17 g. of iron form 4.53 g. of Fe 2 O 3 , what is 
 the atomic weight of iron ? 
 
 38. If 8019 cc. of a gas, measured over water at 
 + 20 C. and 742.4 mm. pressure, weighed 14 g. when 
 deprived of aqueous vapor, what is the molecular weight ? 
 
 39. If 5647 cc. of a gas, measured over water at 
 + 24 C. and 754.2 mm. pressure, weighed 6.254 g. 
 when deprived of aqueous vapor, what is its molecular 
 weight ? 
 
ATOMIC AND MOLECULAR WEIGHTS 133 
 
 40. A compound of phosphorus, oxygen, and chlorine 
 contained 20.19% of phosphorus, 10.43% of oxygen, 
 and 69. 38% 'of chlorine. The vapor density of the 
 compound as gas = 77.95 and the specific heat of phos- 
 phorus = 0.202. Find the molecular formula of the 
 compound and the atomic weight of phosphorus. 
 
 41. The sp. gr. of phosphorus trichloride is 4.88; 
 what is its molecular weight? 
 
 42. Sodium chloride contains 39.32% of sodium 
 and its molecular weight is 58.5. What is the atomic 
 weight of sodium, on the supposition that there is but 
 1 atom of sodium in the molecule of salt ? 
 
 43. Berzelius obtained 17.554 g. of PbO from 16.2956 
 g. of lead ; find the atomic weight of lead. 
 
 44. CuO, when heated in hydrogen, lost 59.80 g. of 
 oxygen and formed 67.3 g. of water. If O = 16, what 
 is the atomic weight of hydrogen ? 
 
 45. Stas found that 91.46 g. of metallic silver, when 
 heated in a stream of chlorine, yielded 121.4993 g. of 
 pure silver chloride. Calculate from this the atomic 
 weight of chlorine. 
 
 46. Stas found, after adding 7.25682 g. of potassium 
 chloride to 10. 51995 g. of silver dissolved in nitric acid, 
 that 0.0194 g. of silver remained in solution. Calculate 
 from these data the atomic weight of potassium. 
 
 47. Erdmann and Marchand obtained 109.6308 g. of 
 mercury from 118.3938 g. of the red oxide. Calculate 
 the atomic weight of mercury. 
 
 48. If 0.3697 g. of aluminum liberated 0.04106 g. of 
 hydrogen on being dissolved in a strong solution of so- 
 dium hydrate, what is the atomic weight of aluminum ? 
 
134 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 49. Marignac found that 5 g. of strontium chloride, 
 containing 6 molecules of water of hydration, yielded 
 3.442 g. of strontium sulphate. Calculate the equivalent 
 of strontium. 
 
 50. Pure carbon monoxide was passed over red-hot 
 copper oxide; the residual metal and the carbon dioxide 
 formed were weighed; 24.360 g. of oxygen were lost 
 and 67.003 g. of carbon dioxide were obtained. From 
 this calculate the atomic weight of carbon. 
 
 51. One g. of an element is found to combine with 
 oxygen so as to form 2.9 g. of oxide; calculate its 
 equivalent. 
 
 52. If 0.254 g. of a metal, when dissolved in hydro- 
 chloric acid, liberated 116 cc. of hydrogen, measured 
 at + 15 C. and 725 mm., what is the equivalent of 
 the metal? 
 
 53. Phosphine contains 91.17 % of phosphorus and 
 8.83 % of hydrogen ; find the equivalent of phosphorus. 
 
 54. Three oxides of nitrogen contain, respectively, 
 63.63%, 46.66%, and 36.84% of nitrogen; calculate 
 the equivalent of nitrogen in each of them. 
 
 55. A bromide of antimony contains 66.66% of bro- 
 mine. If Br = 80, calculate the equivalent of antimony. 
 
 56. A 1 % sugar solution gives an osmotic pressure 
 of 516 mm. at -f 15 C. What is the molecular weight 
 of sugar? Assume that the sp. gr. of the solution is 1. 
 
 57. The specific heat of an element is -^ ; and its 
 atomic weight is a multiple of 14. Find the atomic 
 weight of the element. 
 
 58. If 200 parts of BaCl 2 give 224.2 of BaSO 4 , 
 what is the atomic weight of barium ? 
 
ATOMIC AND MOLECULAR WEIGHTS 135 
 
 59. The equivalent of lead is found to be 103.5 and 
 that of platinum 48.6; determine the probable atomic 
 weight of both lead and platinum, specific heat of lead 
 being 0.0310 and of platinum 0.0324. 
 
 60. A 1. of oxygen under standard conditions weighs 
 1.43 g. A 1. of a certain element, the molecule of 
 which contains 2 atoms, if vaporized under the same 
 conditions, would weigh 11.43 g. What is the atomic 
 weight of the element ? 
 
 61. When 2.16 g. of silver are treated with chlorine, 
 2.87 g. of AgCl are formed ; calculate the atomic weight 
 of silver. 
 
 62. If 10 g. of the chloride of a certain univalent 
 element are found to contain 60.6% of chlorine, and 
 if the atomic weight of chlorine is 35.5, what is the 
 atomic weight of the other element? 
 
 63. The molecular weight of potassium chloride is 
 74.2. The per cent of potassium in the compound is 
 52.56. The specific heat of potassium is 0.166. What 
 is the atomic weight of the element ? 
 
 64. The molecular weight of lead oxide. PbO, is 
 221.3. The per cent of lead = 92.81. Specific heat of 
 lead = 0.031. What is its atomic weight ? 
 
 65. A compound of hydrogen and sulphur has a 
 molecular weight of 34. The per cent of sulphur 
 in the compound is 94.11. Specific heat of sulphur 
 = 0.163. What is its atomic weight ? 
 
 66. A compound of aluminum and chlorine has a 
 molecular weight of 265.2. Per cent of aluminum is 
 20.36. Specific heat of aluminum = 0.222. What is 
 the atomic weight of aluminum ? 
 
136 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 67. Analysis of uranium chloride shows the com- 
 position : U, 62.7%; Cl, 37.3%. The specific heat 
 of metallic uranium is 0.027. What is the atomic 
 weight of uranium and what the formula of the chloride ? 
 
 68. Find the atomic weight of lead from the follow- 
 ing data : the molecular weight of lead sulphide is 
 249; in 100 parts of lead sulphide there are 83.13 
 parts of lead ; specific heat of lead is 0.031. 
 
 69. The molecular weight of arsenuretted hydrogen 
 is 78. In 100 parts there are 96.15 parts of arsenic, 
 and the specific heat of arsenic is 0.0814. What is the 
 atomic weight of arsenic ? 
 
 70. The molecular weight of carbon disulphide is 
 76, and 100 parts yield 84.21 parts of sulphur; the 
 specific heat of sulphur is 0.163. What is the atomic 
 weight of sulphur, and how many atoms of sulphur 
 are in a molecule of the carbon disulphide ? 
 
 71. The specific heat of silver is 0.056; what is its 
 atomic weight ? 
 
 72. If 35.5 g. of chlorine unite with 48.6 g. of 
 platinum to form platinic chloride and the specific heat 
 of platinum is 0.0324, what is (a) the atomic weight of 
 platinum and (6) the formula of platinic chloride ? 
 
 73. A compound consists of P, 20.19; O, 10.43; 
 Cl, 69.38. The vapor density of the substance in the 
 state of gas is 77.95; the specific heat of phosphorus 
 is 0.1887. Calculate the molecular weight of the com- 
 pound and the atomic weight of phosphorus. 
 
 74. Dumas found, on heating copper oxide in a 
 stream of dry hydrogen, that a certain weight of this 
 
ATOMIC AND MOLECULAR WEIGHTS 137 
 
 substance lost 59.789 g. of oxygen and yielded 67.282 g. 
 of water. Calculate from these numbers the atomic 
 weight of hydrogen. 
 
 75. Marignac obtained 314.894 g. of silver nitrate 
 from 200 g. of silver. Further, 14.110 g. of silver 
 nitrate require 6.191 g. of. potassium chloride for com- 
 plete precipitation, and 10.339 g. of silver dissolved in 
 nitric acid require 5.120 g. of ammonium chloride for 
 precipitation. Calculate the atomic weight of nitrogen 
 from these data. 
 
 76. An oxide of bismuth contains 89.655% of bis- 
 muth ; calculate the equivalent of bismuth. 
 
 77. If 0.334 g. of metallic silver, dissolved in nitric 
 acid, yield a precipitate of silver chloride with hydro- 
 chloric acid which weighed 0.4436 g., what is the 
 equivalent of silver ? 
 
 78. If 3.2 g. of silver chloride, heated in a current 
 of hydrogen, yield 2.4081 g. of metallic silver, what is 
 the equivalent of silver ? 
 
 79. If 5 g. of copper oxide, heated in a current of 
 hydrogen, yield 3.9915 g. of metallic copper, what is 
 the equivalent of copper ? 
 
 80. If 1.665 g. of lead chloride were dissolved in 
 water, and silver nitrate was added to the solution, and 
 the precipitated silver chloride weighed 1.72 g., what is 
 the equivalent of lead ? 
 
 81. Mallet found that 8.2144 g. of ammonium alum, 
 dried by exposure to air at + 21 C. to + 25 C., yielded 
 0.9258 g. of A1 2 O 3 . Taking the following atomic 
 weights: O, 15.961; S, 31.966; N, 14.010, find the 
 atomic weight of aluminum. 
 
138 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 82. Mallet found that 6.9617 g. of AlBr 3 required 
 8.4429 g. of Ag for precipitation of the bromine. If 
 Ag= 107.649 and Br = 79.754, what is the atomic 
 weight of Al as deduced from this result ? 
 
 83. Find the equivalent of aluminum from the fol- 
 lowing data: (a) 5.2632 g. of the metal heated with 
 potash gave hydrogen which, when burned, yielded 
 5. 2562 g. of water; (6) 8.6492 g. of aluminum bro- 
 mide required 10.4897 g. of silver for complete precipi- 
 tation. 
 
 84. One 1. of mercury vapor at the standard tempera- 
 ture and pressure weighs 8.923 g. On heating 118.3938 
 g. of mercuric oxide, Erdmann and Marchand obtained 
 109.6308 g. of mercury. On the assumption that mer- 
 curic oxide is formed by the union of 1 atom of mercury 
 with 1 atom of oxygen, what light do these facts throw 
 on the atomic and molecular weights of mercury ? 
 
 85. By dissolving 0.4442 g. of metallic cobalt in an 
 acid, 177.4 cc. of hydrogen at + 10 C. and 750 mm. 
 pressure are obtained. The specific heat of the metal 
 is 0.107. Calculate the atomic weight of cobalt. 
 
 86. If 4.353 g. of potassium bromide required, for 
 complete precipitation, 3.946 g. of silver dissolved in 
 nitric acid, what is the equivalent of bromine ? 
 
 87. A compound has the following percentage com- 
 position : oxygen, 76.09%; hydrogen, 1.59%; nitro- 
 gen, 22.32%. One 1. of its vapor weighs 2.817 g. 
 What is its molecular weight and formula? 
 
 88. A hydrocarbon consists of carbon, 93.75%; 
 hydrogen, 6.25%. The density (air) of its vapor is 
 4.456. What is its formula ? 
 
ATOMIC AND MOLECULAR WEIGHTS 139 
 
 89. A gas has the following composition : nitrogen, 
 30.56% ; oxygen, 69.44%. One 1. of the gas weighs 
 2.058 g. What is its molecular weight and formula ? 
 
 90. A compound has the following percentage com- 
 position : H, 1.19%; O, 56.86%; 01,41.95%. One 
 1. of its vapor weighs 3.771 g. What is its molecular 
 weight and formula? 
 
 91. If 4.5 g. of mercury unite with oxygen to form 
 4.86 of mercuric oxide, and the specific heat of mercury 
 is 0.032, what is its atomic weight? 
 
 92. If 25 g. of metallic tin were converted into 
 stannic oxide by heating with nitric acid and then ignit- 
 ing, and the stannic oxide weighed 31.8 g., what is its 
 atomic weight ? The specific heat of tin is 0.056. 
 
 93. Suppose that 0.3697 g. of aluminum liberated 
 0.04106 g. of hydrogen on being dissolved in a strong 
 solution of sodium hydrate. On the assumption that 
 alumina is a sesquioxide, A1 2 O 3 , find from these data 
 the atomic weight of aluminum. 
 
CHAPTER XI 
 
 Electro-chemical Problems 
 
 1. A current deposits 16 g. of silver; how much 
 copper will it deposit ? 
 
 2. What current strength (in amperes) is required 
 to deposit : 20 g. of silver in an hour ; 100 g. of iodine 
 in 5 minutes ; 60 g. of antimony in 3 hours ? 
 
 3. A current deposits 1 g. of sodium ; find weight 
 of Ni deposited. 
 
 4. If a current deposits 32 g. of Cu, how many g. 
 of Al, Na, Mg, Pb, will it deposit ? 
 
 5. Two electrolytic cells, one containing acidulated 
 water and the other lead nitrate solution, are joined 
 in series, and the same current is passed through them 
 until 25 cc. of hydrogen are liberated in the first cell. 
 What weight of lead nitrate will be decomposed in the 
 other cell ? 
 
 6. How many g. of silver will be deposited from a 
 solution of silver nitrate by a current of 2 amperes in 
 50 sec. ? 
 
 7. How many g. of copper will be deposited from 
 a bath of copper sulphate by a current of 5 amperes in 
 30 min. ? 
 
 8. How much would a metal platter increase in 
 weight if it were nickel-plated by a current of 0.5 
 ampere running 5 hr. ? 
 
 140 
 
ELECTRO-CHEMICAL PROBLEMS 141 
 
 9. What is the current strength of a Daniell cell 
 if its copper plate gains 0.7 g. in 40 min. ? 
 
 10. How much current would be needed to make in 
 3 hr. a copper electrotype shell weighing 40 g. ? 
 
 11. How long would it take a current of 5 amperes 
 to produce 0.6 g. of hydrogen by decomposition of 
 water? 
 
 12. Find the electro-chemical equivalent for zinc 
 from the fact that one of the zinc plates in an Edison 
 chemical meter gains 726 g. when 20 amperes pass 
 through it for 30 hr. 
 
 13. If a current of 2 amperes is used to decompose 
 water and produces 2.981 g. of oxygen in 5 hr., what 
 is the electro-chemical equivalent for oxygen ? 
 
 14. The current from a battery liberates in a given 
 time 150 cc. (measured at 0C. and 760 mm.) of the 
 mixed gases from acidified wtfter ; if this same current 
 were passed through a solution of copper sulphate, 
 what weight of copper would be deposited ? 
 
 15. How many coulombs are carried by and will 
 deposit : 20 g. of silver ; 15 g. of antimony ; 30 g. of 
 chlorine ; 60 g. of phosphanion (PO 4 ) ? 
 
 16. If a current of 15 amperes flows for 1 hour 
 and 20 minutes, how many coulombs will pass ? How 
 many ampere-hours will that give ? 
 
 17. If the specific resistance of copper is 0.000001629, 
 what is the resistance of a wire 200 m. long having a 
 cross section of 2 mm. 2 ? 
 
 18. If the specific resistance of German silver is 
 0.0000209, what is the resistance of 150 m. of wire 
 having a cross section of 25 mm. 2 ? 
 
142 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 19. What is the resistance of an electric light carbon 
 12 inches long by | inch in diameter, when its specific 
 resistance is 0.07 ? 
 
 20. How much zinc will be deposited from zinc sul- 
 phate by 3 amperes in 10 minutes? 
 
 21. How much lead will be deposited by a current 
 of J an ampere passing for 90 minutes through lead 
 chloride ? 
 
 22. How much chlorine would be liberated by J an 
 ampere passing through dilute hydrochloric acid for 13 
 hours ? 
 
 23. How much tin will be deposited by 5 amperes 
 flowing 6 hours through a solution of SnCl 2 ? 
 
 24. How many amperes will it take to deposit 2^ 
 Ib. of copper from copper sulphate in 10 hours ? 
 
 25. What is the minimum voltage necessary to de- 
 compose water if the heat of combination of 1 g. of 
 hydrogen with oxygen is 34,180 calories ? 
 
 26. If zinc bromide requires 1.65 volts to decompose 
 it, what is the heat involved by the equivalent weight 
 of zinc in g. combining with bromine ? 
 
 27. If 1 g. of hydrogen, combining with chlorine 
 in the presence of water, evolves 39,315 calories, -what is 
 the voltage required for the decomposition of hydro- 
 chloric acid ? 
 
CHAPTER XII 
 
 Analytical Calculations Strength of Solutions 
 
 1. If a solution of hydrochloric acid contained 44 
 g. of that substance to the L, how many cc. of the solu- 
 tion would be needed to neutralize 20 cc. of the solution 
 of sodium hydroxide containing 60 g. to the 1.? 
 
 2. What weight of sodium hydroxide will neutral- 
 ize 100 g. of sulphuric acid ? What weight of potas- 
 sium hydroxide will neutralize the same ? 
 
 3. If in neutralizing a certain amount of nitric acid 
 with sodium hydroxide, 7.85 cc. of water are formed, 
 how much nitric acid and how much sodium hydroxide 
 have been employed ? 
 
 4. llow many g. of a 5 % solution of KOH will be 
 required to neutralize 10 g. of a 10 % solution of 
 H 2 S0 4 ? 
 
 5. If 10 g. of commercial caustic soda, dissolved in 
 water, required 116.3 g. of a 10 % sulphuric acid to 
 neutralize the solution, what percentage of pure NaOH 
 did the substance contain ? 
 
 6. If 10 g. of commercial nitric acid were exactly 
 neutralized by the addition of 58.6 g. of a 10 % solu- 
 tion of potassium hydroxide, what was the strength of 
 the acid in pure HNO 3 ? 
 
 143 
 
144 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 7. If a solution contained 50 g. of ammonium 
 hydroxide to the 1., how many cc. of a 10 % solution of 
 hydrochloric acid will be needed to neutralize 60 cc. of 
 the ammonium hydroxide solution ? 
 
 8. What weight of potassium hydroxide will neu- 
 tralize 36.2 g. of hydrochloric acid? 
 
 9. What weight of sodium hydroxide will neutral- 
 ize 36.2 g. of hydrochloric acid ? 
 
 10. What weight of potassium hydroxide will neu- 
 tralize 62.7 g. of nitric acid ? 
 
 11. What weight of sodium hydroxide will neutral- 
 ize 62.7 g. of nitric acid ? 
 
 12. What weight of potassium hydroxide will neu- 
 tralize 97.6 g. of sulphuric acid? 
 
 13. What weight of sodium hydroxide will neutral- 
 ize 97.6 g. of sulphuric acid? 
 
 14. Suppose we have a molar solution of sodium 
 hydroxide and a hydrogen chloride solution of unknown 
 strength. If 50 cc. of the former require 62 cc. of the 
 latter for neutralization, what is the strength of the 
 hydrochloric acid solution ? 
 
 15. Calculate the weight of sodium hydroxide that 
 would be neutralized by 50 cc. of a solution of sul- 
 phuric acid of density 1.23 and containing 31% by 
 weight of pure acid. 
 
 16. What volume of centinormal sulphuric acid solu- 
 tion would be required to neutralize 0.008 g. of K 2 CO 3 ? 
 
 17. HBr solution having a density of 1.515 contains 
 49.8 % of the gas. How many g. AgNO 3 are needed 
 to precipitate 250 cc. of the solution? 
 
ANALYTICAL CALCULATIONS 145 
 
 18. If 75 cc. of HC1 solution neutralize 60 cc. of 
 NaOH containing 0.003 g. of the alkali per cc., what 
 was the weight of the acid in 1 cc. of its solution ? 
 
 19. A solution of KOH contains 0.02 g. per cc. and 15 
 cc. of it neutralize 40 cc. of an HC1 solution. Find the 
 number of g. of HC1 contained in 30 cc. of the solution. 
 
 20. How much ammonium hydroxide, sp. gr. 0.88, 
 and water will have to be mixed to give 200 cc. of 
 ammonium hydroxide, sp. gr. 0.96? 
 
 21. How much nitric acid, sp. gr. 1.42, and water 
 are needed to make 6 1. of nitric acid, sp. gr. 1.26 ? 
 
 22. How much sulphuric acid, sp. gr. 1.7, and how 
 much water are required to make 400 cc. of sp. gr. 
 1.18? 
 
 23. How much ammonium hydroxide, sp. gr. 0.9, 
 and water must be mixed to give 4 1. of sp. gr. 0.96 ? 
 
 24. Given 2 1. of dilute sulphuric acid, sp. gr. 1.2, 
 which is to be used up in diluting concentrated sul- 
 phuric acid, sp. gr. 1.82, to an acid of sp. gr. 1.3, how 
 much concentrated acid must be added ? 
 
 25. A solution of lime water contains 5 g. of lime to 
 the 1.; how many cc. of N/10 H 2 SO 4 are needed to 
 precipitate all of the lime from 10 1. of the lime water 
 solution ? 
 
 \ 26. If 300 cc. of a solution of caustic potash contain- 
 ing 40 g. KOH per 1. are required to neutralize 100 cc. 
 of sulphuric acid and the same volume of nitric acid, 
 what is the amount of acid in each solution ? 
 
 27. What volume of aqueous hydrochloric acid, con- 
 taining 36.5 g. HC1 per 1., will be required to neutral- 
 ize 224.5 g. of Na 2 CO 3 , 10 H 2 O ? 
 
146 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 28. How many Ib. of 15 % HC1 are needed to neu- 
 tralize 2000 Ib. of 
 
 ^ 29. Calculate the weight of crystallized oxalic acid 
 (C 2 H 2 O 4 , 2 H 2 O) required for a solution which is to be 
 made up to 500 cc. in volume at N/2 strength. 
 
 30. If 1 1. of a solution of sodium hydroxide contains 
 35 g. of NaOH, how many g. of nitric acid would be 
 needed to neutralize exactly 60 cc. of the solution ? 
 
 31. How much of the following substances are in 
 their molar solutions : hydrogen bromide ; potassium 
 hydroxide ; and potassium iodide ? 
 
 32. How much of a tenth-normal hydrochloric acid 
 solution is necessary to neutralize 3 g. of strontium 
 hydroxide ? 
 
 33. Determine the normality of a sodium dichromate 
 solution, 50 cc. of which oxidized 3.85 g. of ferrous 
 ammonium sulphate [FeSO 4 , (NH 4 ) 2 SO 4 ,6 H 2 O] to the 
 ferric salt. 
 
 34. How many g. of 10 % (by weight) solution of 
 barium chloride are needed to precipitate as barium 
 sulphate the SO 4 in 2 g. of pure magnesium sulphate? 
 
 35. How many g. of a 5 % solution of ammonium 
 oxalate are needed to precipitate completely as calcium 
 oxalate the lime in 1 g. of calcium carbonate ? 
 
 36. How many g. of 15 % solution of NaNH 4 HPO 4 
 are necessary to precipitate completely the zinc in a 
 solution containing 0.50 g. of zinc? 
 
 37. How many Ib. of 25% sulphuric acid will be 
 required to neutralize 2000 Ib. of NaHCO 3 ; of 
 CaCO 3 ? 
 
ANALYTICAL CALCULATIONS 147 
 
 38. How much iron is present in 10 cc. of ferrous sul- 
 phate solution, 15 cc. of which required 60 cc. of a solu- 
 tion of K 2 O 2 O 7 containing 4.902 g. of the dry salt per 1.? 
 
 39. A solution, A, contains 100 g. of KOH to the 1. 
 A solution, B, contains 100 g. of H 2 SO 4 to the 1. What 
 volume of solution A is needed to neutralize exactly 
 25 cc. of S? 
 
 40. Calculate the number of g. per 1. to give normal 
 solutions of NaCl ; ofBad 2 ; of Na 3 PO 4 ; of KOH. 
 
 41. Calculate the amounts needed to make 5 1. of N/10 
 silver nitrate ; 2 1. of N/10 sodium bromide ; 1 1. of 
 N/20 K 2 CO 3 . 
 
 42. What weight of iron in the ferrous condition will 
 100 cc. of N/10 KMnO 4 oxidize? 
 
 43. 4 g. of pure KMnO 4 are dissolved and diluted 
 to 1 1. ; how many mg. of active oxygen are contained 
 in each cc. ? What will be its strength in terms of iron ; 
 of oxalic acid? 
 
 44. If 35 g. of FeSO 4 ,7H 2 O are dissolved and di- 
 luted to 1 1., how many ing. of active oxygen will each 
 cc. absorb? 
 
 45. How many g. of NaOH must be added to 2 1. of 
 NaOH solution, the strength of which is 1 cc. = 0.045 g. 
 H 2 SO 4 , to make it a normal solution? How much 
 water to make it N/2 solution ? 
 
 46. How many g. per 1. of KMnO 4 will give a so- 
 lution of such strength that 1 cc. = 1 % of iron when 
 0.5 g. is taken for analysis? 
 
 47. Given a solution of K 2 Cr 2 O 7 , 1 cc. = 0.005 g. 
 iron, how many g. of KMnO 4 per 1. will give a solution 
 of equal oxidizing strength? 
 
148 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 48. What volumes of N/2 and of N/10 H 2 SO 4 must 
 be mixed to give 2 1. of N/5 H 2 SO 4 ? 
 
 49. A solution of hydrochloric acid is desired to be 
 made exactly normal. If 40 cc. of the solution neu- 
 tralized 50 cc. of 0.84 N sodium hydroxide solution, 
 what volume of water must be added per 100 cc. of the 
 acid solution ? 
 
 50. A solution of sodium hydroxide is desired to be 
 made exactly 0.5 N. If 32 cc. of the solution at hand 
 were required for the titration of 28 cc. of 0.8 N hy- 
 drochloric acid, what volume of water must be added per 
 100 cc. of the alkaline solution ? 
 
 51. A solution of sodium carbonate is desired to be 
 made exactly 0.05 N. If 24 cc. of the solution at hand 
 neutralized 9.6 cc. of 0.12 N hydrochloric acid solu- 
 tion, what weight of anhydrous salt, Na 2 CO 3 , must be 
 added per 100 cc. of solution? 
 
 52. Calculate the volume of nitric oxide that could 
 be evolved by the action of copper upon 1000 cc. of a 
 N/7 nitric acid solution. 
 
 53. An excess of iron sulphide was added to 500 cc. 
 of a solution of sulphuric acid. The volume of hydro- 
 gen sulphide set free measured 4640 cc. Calculate the 
 normality of the acid. 
 
 54. An excess of sodium sulphite was added to 400 
 cc. of a solution of hydrochloric acid. The volume of 
 sulphur dioxide set free measured 5600 cc. Calculate 
 the normality of the acid. 
 
 55. Suppose that 1400 cc. of ammonia were passed 
 into 500 cc. of N/2 hydrochloric acid solution. Calcu- 
 late the normality of the hydrochloric acid still present. 
 
ANALYTICAL CALCULATIONS 149 
 
 56. If 50 cc. of N/5 hydrochloric acid solution neu- 
 tralized 40 cc. of an unknown alkaline solution, and 300 
 cc. of a sulphuric acid solution neutralized 60 cc. of this 
 same alkaline solution, what is the normality of the sul- 
 phuric acid? 
 
 57. If 200 cc. of a barium hydroxide solution were 
 required in the titration of 40 cc. of an acid solution, 
 and 100 cc. of this acid solution exactly neutralized 80 
 cc. of N/2 alkaline solution, what is the normality of 
 the barium hydroxide solution ? 
 
 58. If 600 cc. of a sulphuric acid solution, when acted 
 upon by an excess of zinc, evolved 1242 cc. of hydrogen, 
 what is the normality of the acid ? 
 
 59. If 400 cc. of an acid solution, when acted upon 
 by an excess of zinc, evolved 2430 cc. of hydrogen, 
 measured over water at +21 C. and 747.5 mm., what 
 is the normality of the acid? 
 
 60. Calculate the normality of a solution of potassium 
 carbonate, 200 cc. of which, when treated with an excess 
 of acid, evolved 4502 cc. of carbon dioxide. 
 
 61. A slight excess of barium chloride solution was 
 added to 400 cc. of a solution of sulphuric acid. From 
 the weight of barium sulphate precipitated, 4.12 g., 
 calculate the normality of the acid. 
 
 62. If 50 cc. of a solution of hydrogen peroxide were 
 required to decolorize 400 cc. of N/5 potassium perman- 
 ganate solution (acidulated), what is the percentage 
 concentration of the hydrogen peroxide solution? 
 
 63. Calculate the weight of a crystallized oxalic acid 
 required for the reduction of 100 g. of potassium per- 
 manganate in acid solution. What volume of carbon 
 dioxide, at standard conditions, would be liberated ? 
 
150 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 64. If 400 cc. of N/4 potassium hydroxide solution 
 were required for the neutralization of 600 cc. of an 
 unknown acid solution, what is the normality of this 
 acid solution? 
 
 65. If 500 cc. of N/10 acid solution were required 
 for the neutralization of 25 cc. of a solution of sodium 
 hydroxide, what is the normality of this latter solution? 
 
 66. What volume of N/10 acid solution will be 
 required in the t titration of 440 cc. of N/4 sodium 
 hydroxide solution? 
 
 67. What volume of N/6 alkaline solution will be re- 
 quired in the titration of 254 cc. of N/10 acid solution? 
 
 68. Calculate the weight of hydrogen chloride pres- 
 ent in 400 cc. of a hydrochloric acid solution which re- 
 quired 320 cc. of N/4 alkaline solution for titration. 
 
 69. Calculate the weight of sulphuric acid present in 
 150 cc. of a solution which required 48.1 cc. of 0.78 N 
 alkali for titration. 
 
 70. An excess of silver nitrate solution was added to 
 350 cc. of a solution of hydrochloric acid. The pre- 
 cipitate of silver chloride weighed 7.54 g. Calculate 
 the normality of the acid. 
 
 71. The bromine set free by the action of manganese 
 dioxide upon a hydrobromic acid solution was passed 
 into a solution of potassium iodide. If 200 cc. of N/10 
 sodium thiosulphate solution were required for the ti- 
 tration of the free iodine, what is the weight of the 
 bromine evolved? 
 
 72. Determine the purity of a sample of manganese 
 dioxide, 2.2 g. of which, with excess of hydrochloric 
 
ANALYTICAL CALCULATIONS 151 
 
 acid, set free sufficient chlorine to liberate a quantity of 
 iodine that required 250 cc. of N/5 sodium thiosulphate 
 solution for titration. 
 
 73. What weight of iron will be required for inter- 
 action with 400 cc. of N/5 hydrochloric acid? 
 
 74. What weight of sodium carbonate will be required 
 for interaction with 600 cc. of N/8 sulphuric acid? 
 What volume of carbon dioxide (at standard conditions) 
 will be evolved ? 
 
 75. What weight of sodium hydrogen carbonate, 
 NaHCO 3 , will be required for interaction with 600 cc. 
 of N/8 sulphuric acid? What volume of carbon diox- 
 ide will be evolved? 
 
 76. If 50 cc. of an acidulated potassium permanga- 
 nate solution were reduced by 2.4 g. of anhydrous 
 oxalic acid, what is the normality of the permanganate 
 solution? 
 
 77. W T hat weight of sulphur dioxide will be oxidized 
 by 50 g. of potassium permanganate in alkaline solution ? 
 
 78. What weight of sodium dichromate must enter 
 into reaction with a hydrochloric acid solution in order 
 to liberate 100 g. of chlorine at standard conditions? 
 
 79. Determine the normality of a potassium dichro- 
 mate solution, 25 cc. of which oxidized 1.24 g. of ferrous 
 sulphate to the ferric salt. 
 
 80. What volume of hydrogen sulphide, at 4- 24 C. 
 and 750 mm. pressure, can be oxidized by 10 g. of 
 potassium dichromate in acid solution? 
 
 81. What weight of potassium dichromate, in acid 
 solution, will be reduced by 1653.5 cc. of sulphur diox- 
 ide at + 22 C. and 745 mm. pressure? 
 
152 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 82. What volume of hydrogen sulphide will be re- 
 quired for the reduction of 100 g. of ferric chloride, 
 FeCl 3 , to the ferrous salt ? 
 
 83. What volume of gaseous product may be obtained 
 in the decomposition of 100 cc. of ammonia by heated 
 cupric oxide ? 
 
 84. What volume of hydrogen sulphide will be re- 
 quired to reduce 200 cc. of N/10 potassium dichromate 
 solution (acidulated) ? 
 
 85. Calculate the volume of hydrogen sulphide, at 
 standard conditions, that can be oxidized by 4 g. of 
 potassium permanganate in acid solution. 
 
 86. What weight of sulphur dioxide can be oxidized 
 by 200 g. of potassium permanganate in acid solu- 
 tion ? 
 
 87. A sample of sodium chromate, weighing 1.6780 
 g., gave upon analysis 1.4620 g. of sodium sulphate. 
 What was the percentage of sodium oxide in the 
 sample ? 
 
 88. Calculate the weight of sulphur precipitated in 
 the reduction of 100 g. of ferric chloride to the ferrous 
 salt by the action of hydrogen sulphide. 
 
 89. What weight of potassium dichromate will 1000 
 cc. of hydrogen sulphide reduce in acid solution ? 
 
 90. Calculate the percentage purity of a quantity of 
 potassium ferrocyanide, 0.5793 g. of which gave upon 
 analysis 0.4650 g. of potassium sulphate. 
 
 91. What is the percentage of potassium sulphate in 
 a sample of common alum which analyzed -33.51 % sul- 
 phur trioxide? 
 

 ANALYTICAL CALCULATIONS 153 
 
 92. What is the percentage of copper carbonate in a 
 sample of malachite which on analysis gave 57.1 % copper ? 
 
 93. A sample of carnallite (KC1, MgCl 2 , 6 H 2 O) on 
 analysis gave 35.34% chlorine; what is the percentage 
 of magnesium chloride present? 
 
 94. Calculate the percentage purity of a sample of 
 marble which on analysis gave 39.6% calcium. 
 
 95. Calculate the percentage of potassium chloride 
 in a sample of carnallite (KC1, MgCl 2 , 6 H 2 O) which on 
 being analyzed gave 37.72% chlorine. 
 
 96. Calculate the percentage of calcium oxide, CaO, 
 present in a sample of marble, CaCO 3 , which on being 
 analyzed gave 43.8% carbon dioxide. 
 
 97. Two g. of impure potassium dicarbonate required, 
 when titrated cold, in a dilute solution, 6 cc. of N/10 
 H 2 SO 4 ; 2 g., when titrated boiling hot, required 18 
 cc. of normal H 2 SO 4 . What are the percentages of 
 K 2 CO 3 andof KHCOo? 
 
 A O O 
 
 98. What volumes of N/2 and of N/10 H 2 SO 4 must 
 be mixed to give 2 1. of N/5 H 2 SO 4 ? 
 
 99. A N/10 iodine solution is 2 % too strong. How 
 many cc. of a N/100 iodine solution must be added to 
 1 1. to make it right? 
 
 100. How much more normal NaOH will it take to 
 neutralize 1 g. of NaHSO 4 than normal KOH to neu- 
 tralize 1 g. KHSO 4 ? 
 
 101. Suppose that 0.2 g. of a nitrogenous organic 
 compound were heated w r ith soda lime and the NH 3 
 evolved was caught in 50 cc. N/10 HC1, and that the 
 excess of HC1 was neutralized by 14 cc. of N/5 NaOH ; 
 what was the percentage of nitrogen ? 
 
154 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 102. Iii 1 g. of an antimony alloy the antimony 
 was determined by N/10 Na 2 S 2 O 3 and 24.2 cc. were 
 required ; what is the percentage of antimony ? 
 
 103. What amount of type metal must be taken for 
 analysis so that the burette shall read percentage of 
 antimony when N/10 Na 2 S 2 O 3 is used? 
 
 104. Five g. of bleaching powder were mixed in a 
 mortar with water and diluted to 1 1. ; 50 cc. of this 
 required 30 cc. of N/10 Na 3 AsO 3 solution. What is 
 the percentage of available chlorine ? Under these con- 
 ditions, what fraction of normal will read percentage 
 direct? 
 
 105. To 50 cc. of a solution of chlorine an excess of 
 potassium iodide was added ; the liberated iodine was 
 then estimated by a N/10 solution of Na 2 S 2 O 3 , starch 
 being used as an indicator; and 22.5 cc. of Na 2 S 2 O 3 
 solution were needed. What is the strength of the 
 chlorine solution? 
 
 106. How much more normal NaOH will it take to 
 neutralize 1 g. of HC1 than 1 g. of HBr? 
 
 107. How many g. per 1. of K 2 Cr 2 O 7 will give a solu- 
 tion of such strength that 1 cc. = 1 % of iron when 0.60 
 g. is taken for analysis ? 
 
 108. How many g. of Na 2 S 2 O 3 , 5 H 2 O per 1. will give 
 a solution such that 1 cc. =0.5% Cu when 1 g. is 
 taken for analysis? 
 
 109. How much water must be added to 2 1. of 
 KMnO 4 , 1 cc. = 0.0065 g. iron, to make it N/10? 
 
 110. How much water must be added to 3 1. of 
 K 4 Fe(CN) 6 , 1 cc. = 0.0115 g. zinc, to make it read 
 percentage directly when 1 g. is taken for analysis? 
 
ANALYTICAL CALCULATIONS 155 
 
 111. Given a solution of K 2 Cr 2 O 7 , 1 cc. = 0.0042 g. 
 Fe, how many g. per 1. of KMnO 4 will give a solution 
 of equal strength? 
 
 112. Given a solution of KMnO 4 , 1 cc. = 0.0056 g. 
 of iron, what is its strength in terms of manganese 
 by the Volhard method and by the Ford- Williams 
 method? 
 
 113. What is the strength of N/10 KMnO 4 in terms 
 of H 2 C 2 O 4 ; of CaO ; of CaCO 8 ; of CaSO 4 ? 
 
 114. What is the strength of N/10 KMnO 4 in terms 
 of P and of MoO 3 according to Noyes' method? 
 
 115. What is the strength of a N/10 sodium thio- 
 sulphate solution in terms of iodine ; of copper ? 
 
 116. What is the strength of a N/5 iodine solution 
 in terms of SO 2 ; H 2 SO 3 ; Na 2 SO 3 ? 
 
 117. How many cc. of N/5 Na 2 S 2 O 3 solution will be 
 required to react with the iodine liberated by 20 cc. of 
 a N/10 K 2 O 2 O 7 solution? 
 
 118. How many g. of copper will give, when pre- 
 cipitated by potassium iodide, sufficient iodine to re- 
 quire 20 cc. of N/10 SO 2 solution? How many for 
 10 cc. of N/10 Na 2 S 2 O 3 solution? 
 
 119. Five g. of pig iron took 12 cc. of N/100 iodine 
 solution ; what is the percentage of sulphur ? 
 
 120. If 1.5 g. of pig iron took 78 cc. of N/10 
 KMnO 4 , what is the percentage of phosphorus? 
 
 121. How much NaOH must be added to 1.890 1. of 
 NaOH solution, the strength of which is 1 cc. = 0.045 g. 
 H 2 SO 4 , to make it normal? How much water to make 
 
 it N/2? 
 
156 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 122. One g. of a rock gave, on analysis : combined 
 sodium and potassium sulphates, 0.150 g. ; and plati- 
 num from K 2 PtCl 6 , 0.1127 g. What are the percentages 
 of K 2 O andNa 2 O? 
 
 123. Which is more economical for neutralizing an 
 alkali, 60 % HNO 3 at 6 cts. per Ib. or 20 % HC1 at 3 
 cts. per Ib. ? 
 
 124. Which is the more economical oxidizing agent, 
 KNO 3 at 5 cts. a Ib. or NaNO 3 at 51 cts. a Ib. ? 
 
 125. Calculate the number of g. per 1. to give normal 
 solutions of oxalic acid; of tartaric acid; of acetic 
 acid ; of citric acid. 
 
 126. Calculate the number of g. per 1. to give half 
 normal solutions of I ; of Na 2 S 2 O 3 , 5 H 2 O ; of SO 2 . 
 
 127. Calculate the amounts necessary to make 2 1. 
 of N/10 NaCl and NaBr. 
 
 128. Calculate the strength of N/20 KMnO 4 to be 
 used in titrating K 4 Fe(CN) 6 . 
 
 129. What is the strength of N/10 KMnO 4 in terms 
 of Fe; Fe 2 O 8 ; Fe 3 O 4 ; FeSO 4 , 7H 2 O? 
 
 130. How many g. of oxalic acid in a molar and in 
 a normal solution? 
 
 131. How many cc. of a N/3 solution of AgNO 3 will 
 precipitate 20 cc. of a 10% sodium chloride solution? 
 
 132. What weight of As 2 O 3 will be necessary to make 
 a twice molar and a N/2 solution ? 
 
 133. One g. of coal gave 0.2634 g. of BaSO 4 by 
 Eschka's Method; 1 g. of MgO and 0.5 g. of Na 2 CO 3 
 were used. It was found that both contained sulphur ; 
 
ANALYTICAL CALCULATIONS 157 
 
 10 g. of MgO and 5 g. of Na 2 CO 3 (together) gave 
 0.1654 g. of BaSO 4 . What is the percentage of sul- 
 phur in the coal? 
 
 134. Suppose that 1 g. of silver is dissolved in nitric 
 acid and to it is added 0.25 g. of pure dry sodium chlo- 
 ride. What percentage of the silver remains in solution ? 
 
 135. Suppose that 0.25 g. of sodium bromide is 
 added to a solution of 1 g. of silver; what percent- 
 age of silver remains in solution? 
 
 136. A dolomite contains 98 % of calcium and mag- 
 nesium carbonates, 2 % of SiO 2 , and 10 % of MgO ; 
 what is the percentage of CO 2 ? 
 
 137. Calculate the chemical factors for (a) (NH 4 ) 2 O 
 from 2NH 4 C1, PtCl 4 ; (5) for K in 2 KC1, PtCl 4 ; 
 (<?) for P in Mg 2 P 2 O 7 ; (cT) for Fe 2 O 3 from Fe 3 O 4 . 
 
 138. If 0.5 g. of platinum remains after the ignition 
 of the precipitate of the double salt, 2 NH 4 C1, PtCl 4 , 
 derived from 1 g. of an ammonium compound, calculate 
 the percentage of NH 3 in the latter. 2 NH 4 C1, PtCl 4 = 
 2NH 3 +2HCl + 2Cl 2 + Pt. 
 
 139. What weight of Mn 3 O 4 corresponds to 1 g. of 
 Mn 2 P 2 7 ? 
 
 140. How many cc. of aqueous ammonia (sp. gr. == 
 0.96), containing 9.90% of NH 3 by weight, will be re- 
 quired to precipitate the iron as Fe(OH) 3 from 1 g. 
 of (NH 4 ) 2 SO 4 , FeSO 4 , 6 H 2 O ? 
 
 141. How many cc. of HNO 3 (sp. gr. = 1.135), con- 
 taining 20 % of HNO 3 by weight, are required to oxi- 
 dize the iron in 1 g. of FeSO 4 , (NH 4 ) 2 SO 4 , 6 H^O, in 
 the presence of sulphuric acid? 6 FeSO 4 + 2 HNO 3 + 
 3 H 2 S0 4 = 3 Fe 2 (S0 4 ) 3 + 2 NO + 4 H 2 O. . 
 
158 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 142. The ignited precipitate of Fe 2 O 3 -f- A1 2 O 3 from 
 1.5 g. of a silicate weighs 0.4069 g. ; this mixture loses 
 0.0200 g. when ignited in hydrogen. What is the per- 
 centage of Fe 2 O 3 and A1 2 O 3 in the sample? Fe 2 O 3 -f 
 3 H 2 = 2 Fe + 3 H 2 O. 
 
 143. How many cc. of " magnesia mixture " (64 g. 
 MgCl 2 per 1.) will be required to precipitate the arsenic 
 from 0.2 g. As 2 S 3 after oxidation to arsenic acid? 
 
 H 3 As0 4 + MgCl 2 + 3 NH 4 OH = MgNH 4 AsO 4 + 
 2 NH 4 C1 + 3 H 2 0. 
 
 144. How many cc. of sulphuric acid (sp. gr. = 1.75), 
 containing 81 % H 2 SO 4 by weight, are necessary to re- 
 place the nitric acid in the nitrates formed from 5 g. 
 of a brass containing 65 % Cu, 34.5 % Zn, and 0.5 % Pb? 
 
 145. If 5.23 g. of brass yield 0.0345 g. of PbSO 4 , 
 and subsequently 0.0031 g. of PbO 2 on electrolysis of 
 the filtrate, what is the percentage of Pb in the brass? 
 
 146. If in the analysis of a brass containing 65% 
 copper, an error is made in weighing a 5 g. portion, by 
 which 0.001 g. too much is weighed out, what would 
 be the percentage of copper as determined? If the 
 same error is made in weighing 0.2 g. of apatite con- 
 taining 40 % P 2 ^5' wna t will be the apparent percent- 
 age? What will be the percentage error in each 
 case? 
 
 147. If the dry cupric sulphide from 0.82 g. of brass 
 loses 0.1345 g. on ignition in hydrogen, what is the 
 percentage of copper in the brass? 2 CuS = Cu 2 S + S. 
 
 148. If 1.5 g. of glass yield 0.38 g. KC1 + NaCl, 
 from which 0.646 g. 2 KC1, PtCl 4 is obtained, what is 
 the percentage of Na 2 O in the glass? 
 
ANALYTICAL CALCULATIONS 159 
 
 149. How many cc. of an ammonium oxalate solu- 
 tion [(NH 4 ) 2 C 2 O 4 , H 2 O] (40 g. per 1.) are required 
 to precipitate the calcium as oxalate from 1 g. of apa- 
 tite [Ca 3 (PO 4 ) 2 , CaCl 2 ]? How many cc. of "mag- 
 nesia mixture" (containing 64 g. MgCl 2 per 1.) are 
 necessary to combine with the phosphoric acid in the 
 same weight of apatite ? 
 
 150. If a calcium oxalate precipitate (which is con- 
 taminated by silica) from 0.83 g. of dolomite is ignited 
 under such conditions that the decomposition products 
 may be passed through Ba(OH) 2 solution, and the 
 resulting precipitate of barium carbonate is found, on 
 drying, to weigh 0.9500 g., what is the percentage of 
 CaO in the sample? 
 
 151. How many cc. of a potassium tetroxalate solu- 
 tion (KHC 2 O 4 , C 2 H 2 O 4 , 2 H 2 O), containing 50 g. per 
 1., would be required to precipitate the calcium from 
 1 g. of a sample of dolomite yielding 2% Fe 2 O 3 , 10% 
 MgO, and 45% CO 2 , assuming the iron, magnesium, 
 and calcium to be present wholly as carbonates, the 
 iron as ferrous carbonate? 
 
 152. A mixture of BaO and CaO weighing 0.2438 g. 
 yields 0.4876 g. of mixed sulphates. What is the 
 weight of each oxide in the original mixture? 
 
 153. Calculate the percentage of pure Na 2 CO 3 in an 
 impure sample from the following data : crucible + 
 SiO 2 = 20.0697 g. ; crucible + SiO 2 + Na 2 CO 3 (im- 
 pure) = 20.3264 g. ; crucible + SiO 2 (excess) +Na, 2 SiO 3 
 (after fusion) = 20.2239 g. Assume the reaction to be 
 Na 2 CO 3 + Si0 2 = Na 2 Si0 3 + CO 2 . 
 
 154. A sample of pyrite weighing 0.5 g. yields 1.6 g. 
 BaSO 4 . Calculate the per cent of FeS 2 in the sample. 
 
160 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 155. How much crude cream of tartar should be 
 taken for an analysis in order that the number of cc. 
 of N/2 NaOH solution required to react with it shall 
 represent directly the percentage of KHC 4 H 4 O 6 ? How 
 much oxalic acid in order that each cc. of N/10 KMnO 4 
 may represent 1 % C 2 H 2 O 4 , 2 H 2 O? 
 
 KHC 4 H 4 O 6 + NaOH = KNaC 4 H 4 O 6 + H 2 O. 
 
 156. What weight of potassium ferrocyanide [K 4 Fe 
 (CN) 6 , 3 H 2 O] should a normal solution contain for 
 use as a reducing agent? 
 
 10 K 4 Fe(CN) 6 , 3 H 2 O +2 KMnO 4 + 8 H 2 SO 4 = 
 10 K 3 Fe(CN) 6 + 6 K 2 SO 4 + 2 MnSO 4 + 8 H 2 O + 
 30 H 2 0. 
 
 157. Calculate the percentage of carbon dioxide in a 
 sample of calcium carbonate from the following data : 
 
 Total volume N/2 HC1 = 35 cc. ; total volume N/10 
 NaOH = 15 cc. ; weight carbonate = 1.00 g. 
 
 158. Calculate the weight of KHC 2 O 4 , C 2 H 2 O 4 , 
 2 H 2 O necessary for a 1. of normal solution, (a) as a 
 standard acid solution, (5) as a reducing agent. 
 
 KHC 2 O 4 , C 2 H 2 O 4 , 2 H 2 O + 2 MnO 2 + 3 H 2 SO 4 = 
 2 MnSO 4 + KHSO 4 + 4 CO 2 + 4 H 2 O + 2 H 2 O. 
 
 159. Given the following data, calculate the percent- 
 age purity of the oxalic acid : 
 
 Standardization: weight CaCO 3 = 1.050 g. ; HC1 
 solution used = 45 cc. ; NaOH solution used =4.8 cc. ; 
 1 cc. NaOH solution = 1.042 cc. HC1 solution. 
 
 Analysis: weight oxalic acid = 1.500 g. ; NaOH 
 solution used = 42.5 cc. ; HC1 solution used = 0.5 cc. 
 
 160. Given the following data, calculate the per- 
 centage purity of the cream of tartar (KHC 4 H 4 O 6 ) : 
 
ANALYTICAL CALCULATIONS 161 
 
 Weight of substance = 2.500 g. ; NaOH solution 
 used = 25.51 cc. ; H 2 SO 4 solution used = 0.5 cc. ; 1 cc. 
 H 2 SO 4 solution = 1.02 cc. NaOH solution ; 1 cc. NaOH 
 solution = 0.0255 g. CaCO 3 . 
 
 161. If 10 cc. of a sulphuric acid solution yield 
 0.1220 g. BaSO 4 , how much must the solution be 
 diluted for an exactly N/10 solution? 
 
 162. If 1 cc. of a potassium bichromate solution will 
 oxidize 0.0066 g. of iron, to what volume must 100 cc. 
 of the solution be diluted to make a N/100 solution ? 
 
 163. Calculate the percentage of iron (Fe) in a 
 sample of limonite from the following data : 
 
 Weight of limonite = 0.55 g. ; K 2 Cr 2 O 7 solution 
 used = 51.1 cc. ; 1 cc. K 2 O 2 O 7 solution = 0.0058 g. Fe ; 
 FeSO 4 solution used = 5 cc. ; 5 cc. of FeSO 4 solution 
 contains 0.008 g. FeO. 
 
 164. A sample of iron wire is dissolved, out of con- 
 tact with air, in 30 cc. of HC1, of which 1 cc. = 0.95 cc. 
 N/2 HC1. The iron requires 40 cc. of N/10 K 2 Cr 2 O 7 
 for oxidation. What excess of HC1 was used over that 
 required for solution ? 
 
 165. How much stannous chloride by weight will be 
 required to reduce the iron from 0.5 g. magnetite 
 (FeO, Fe 2 O 3 ), dissolved out of contact with air ? 
 
 166. How many cc. of HC1 (sp. gr. =1.12) are 
 required to dissolve 0.55 g. limonite (2 Fe 2 O 3 , 3 H 2 O), 
 assuming the only impurity to be 1.5 % quartz ? 
 
 167. If 0.75 g. of a silicate yields 0.4 g. Fe 2 O 3 + 
 A1 2 O 3 , and the iron present requires 20 cc. K 2 Cr 2 O 7 solu- 
 tion [1 cc. = 0.0784 g. FeSO 4 (NH 4 ) 2 SO 4 , 6 H 2 O], cal- 
 culate the percentage of FeO and A1 2 O 3 in the sample. 
 
162 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 168. What weight of iron wire containing 99.85 % Fe 
 will react with the chromium from 0.5 g. of chromite 
 (FeO, Cr 2 O 3 ) ? 
 
 169. Calculate the value of a permanganate solution, 
 of which 1 cc. = 0.008 g. of Fe, in terms of MoO 3 - 
 
 Mn 2 O 7 + 10 FeO = 5 Fe 2 O 3 + 2 MiiO ; 
 7 Mn 2 O 7 + Mo 24 O 37 = 24 MoO 3 + 14 MnO. 
 
 170. Given the following data, calculate the per- 
 centage of iron in the limonite : 
 
 Weight of limonite = 0.55 g. ; KMnO 4 solution used 
 = 30 cc. ; 1 cc. KMnO 4 solution = 0.0084 g. C 2 H 2 O 4 , 
 2 H 2 0. 
 
 171. The calcium oxalate precipitate from 0.5 g. of 
 marble, when treated with sulphuric acid, liberates 
 sufficient oxalic acid to reduce 43 cc. of permanganate 
 solution (1 cc. = 0.0115 g. Fe). Calculate the per- 
 centage of calcium in the marble. 
 
 172. If 1 cc. of KMnO 4 solution will oxidize 0.008 g. 
 iron, calculate the equivalent of the same solution 
 in terms of hydrogen peroxide, and also the volume of 
 oxygen which will be evolved by each cc. of the per- 
 manganate solution during the reaction, assuming that 
 1 cc. of oxygen weighs 0.00143 g. under the existing 
 conditions. 
 
 5 H 2 2 + 2 KMn0 4 + 3 H 2 SO 4 = K 2 SO 4 + 2 MnSO 4 + 
 5O 2 +5H 2 O. 
 
 173. Given the following data, calculate the per- 
 centage of MnO 2 in the pyrolusite : 
 
 Weight of pyrolusite = 0.48 g. ; weight of FeSO 4 , 
 (NH 4 ) 2 SO 4 , 6 H 2 O = 4.3501 g. ; K 2 Cr 2 O 7 solution used 
 = 10 cc. ; 1 cc, K 2 Cr 2 O 7 solution = 0.005 g. Fe. 
 
ANALYTICAL CALCULATIONS 163 
 
 174. Given the following data, calculate the per- 
 centage of MnO 2 in the pyrolusite : 
 
 Weight of pyrolusite = 0.48 g. ; weight of iodine 
 liberated from KI = 1.296 g. 
 
 175. If 1 cc. iodine solution is equivalent in oxidiz- 
 ing power to 0.00149 g. of KBrO 3 , to what volume 
 must 100 cc. be diluted to make a N/20 solution ? 
 
 176. Calculate the percentage purity of the sample 
 of potassium dichromate from the following data : 
 
 Weight of sample = 0.1237 g. ; Na 2 S 2 O 3 solution 
 used = 25 cc. ; 1 cc. Na 2 S 2 O 3 solution = 1.004 cc. iodine 
 solution ; 1 cc. iodine solution = 0.004975 g. As 2 O 3 . 
 K 2 Cr 2 O 7 + 6 KI + 7 H 2 SO 4 = 4 K 2 SO 4 + Cr 2 (SO 4 ) 3 + 
 3I 2 + 7H 2 0. 
 
 177. Calculate the percentage purity of a sample of 
 potassium iodate from the following data : 
 
 Weight of sample = 0.25 g. ; Na 2 S 2 O 3 solution used 
 = 50 cc. ; 1 cc. Na 2 S 2 O 3 solution = 0.015 g. I. 
 
 178. If 1 cc. of an iodine solution has the same 
 oxidizing power as 0.0034 g. of KIO 3 , calculate its 
 value in terms of antimony. 
 
CHAPTER XIII 
 
 Review Systematic and Miscellaneous 
 SYSTEMATIC REVIEW 
 
 1. A pressure of 1000 Ib. per in. 2 is how many Kg. 
 per mm. 2 ? 
 
 2. When the mercury (sp. gr. = 13.59) barometer 
 stands at 76 cm., how high will one of glycerine (sp. 
 gr. = 1.27) stand? 
 
 3. When the mercury barometer stands at 760 mm., 
 how high would one of hydrogen sulphate (sp. gr. = 
 1.83) stand? 
 
 4. When the barometer stands at 31 in., what is it 
 in mm.? 
 
 5. When the barometer stands at 755 mm., what is 
 it in in.? 
 
 6. When the pressure of the air is 750 mm. of mer- 
 cury (sp. gr. = 13.59), what is it (0) in feet of water ; 
 (6) in Ib. per in. 2 ? 
 
 7. If 200 cc. of oxygen are measured off over water 
 at +14 C. and 756 mm., what does the dry normal gas 
 measure ? 
 
 8. How much MnO 2 is required to make 10 1. of 
 oxygen ? 
 
 164 
 
SYSTEMATIC REVIEW 165 
 
 9. What weight and volume of oxygen at +15 C. 
 is obtained on passing CO 2 over 1 Kg. of calcium plum- 
 bate heated to redness and then through slaked lime? 
 Ca 2 Pb( ) 4 + 2 C0 2 = 2 CaCOg + PbO + O. 
 
 10. If 481 g. of BaO 2 are heated, what volume of 
 oxygen at + 17 C. and 800 mm. is evolved? 
 
 11. What would be the volume of the liquefied gas 
 if the density of it is 0.89? 
 
 12. In an experiment the CuO lost 59.789 g. and 
 67.282 g. of water was formed. Calculate the atomic 
 weight of oxygen. 
 
 13. What volume is occupied by 1 g. of liquid hydro- 
 gen (sp. gr. = 0.07) ? If the boiling point is - 238.5 C., 
 what is it in F.? 
 
 14. A balloon holds 64 m. 3 of hydrogen ; how many 
 Kg. does the gas weigh? 
 
 15. How many 1. of hydrogen at -f 10 C. and 770 
 mm. are obtained on passing 2 g. of steam over red-hot 
 iron? 
 
 16. What is the mass of 1 1. of hydrogen measured 
 over water at + 50 C. and 790 mm. ? 
 
 17. What volume is occupied by 100 g. of steam 
 measured at +300 C.? 
 
 18. What is the volume of 1000 g. of (a) sea water 
 (sp. gr. = 1.026); (6) ice (sp. gr. = 0.92)? 
 
 19. A block of ice (sp. gr. = 0.92) weighs 280 Kg.; 
 find its volume. 
 
 20. If the density of ice is 0.92, what volume will 
 1000 cc. of water at + 4 C. occupy when frozen? 
 
 21. An iceberg floats in sea water with 30,000 m. 3 
 above the sea ; what is the total volume of the berg ? 
 
166 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 22. If 100 g. of gypsum are heated, what volume of 
 steam at + 300 C. is given off? 
 
 23. If 88.88 parts of oxygen unite with 11.11 parts 
 of hydrogen, and the equivalent of oxygen be 100, what 
 is the equivalent of hydrogen? 
 
 24. If 500 cc. of hydrogen at +39 C. are exploded 
 with 500 cc. of oxygen under a pressure of 332.5 mm. 
 what volume of which gas is left? 
 
 25. How much water must be electrolyzed to give a 
 1. of gas at + 15 C. and 740 mm.? 
 
 26. Find the density of steam at + 300 C. referred 
 to air at C. A Ib. of dry steam at + 374 F. occu- 
 pies how many ft. 3 ? 
 
 27. How many g. does a ft. 3 of aqueous vapor meas- 
 ure at + 212 F. and 30 in. of mercury weigh? 
 
 28. What do 100 1. of nitrogen weigh? 
 
 29. When 100 g.' of Pb(NO 3 ) 2 were heated, they 
 were found by Svanberg to leave 67.4016 g. of PbO. 
 If O = 100 and Pb = 1294, what is the atomic weight 
 of nitrogen ? 
 
 30. What volume is occupied by 10,000 g. of HNO 3 
 (sp.gr. =1.53)? 
 
 31. What is the least quantity of H 2 SO 4 which can 
 be used to decompose 500 g. of KNO 3 ? 
 
 32. How much KNO 3 and what volume of H 2 SO 4 (sp. 
 gr. =1.84) must be distilled together to form a 1. of 
 HNO 3 (sp. gr. = 1.53) ? 
 
 33. How many oz. of AgNO 3 are formed by the 
 action of HNO 3 (sp. gr. = 1.4) upon 1000 g. of Ag? 
 
 34. How much NH 4 NO 3 is required to make 40 1. of 
 N 2 0? 
 
SYSTEMATIC REVIEW 167 
 
 35. What volume of hydrogen is required to combine 
 with the oxygen contained in 10 g. of nitrous oxide? 
 
 36. What volume of NO at + 13 C. is obtained on 
 dissolving 25 g. of Cu in HNO 3 ? 
 
 37. What volume of oxygen is required to convert 
 10 g. of NO in presence of water into HNO 3 ? 
 
 2NO + H 2 + 30 = 2HN0 3 . 
 
 38. How many g. of NH 3 can be obtained from 2140 
 g. of NH 4 C1? 
 
 39. How many g. of NH 3 are obtained on passing 
 3 g. of NO, mixed with excess of H, over hot spongy 
 Pt? 
 
 2 NO + 10 H = 2 NH 3 + 2 H 2 O. 
 
 40. If 2 g. of potassium are heated in NH 3 , how 
 much potassamide and what volume of H at + 15 C. 
 are formed? 
 
 41. If 2 1. of nitrosyl chloride at + 15 C. are passed 
 over warm AgNO 3 , how much N 2 O 5 is formed? 
 
 NO 2 C1 + AgNO 3 = AgCl + N 2 O 5 . 
 
 42. If 100 1. of air are passed over red-hot Cu, how 
 much does the Cu increase in mass? 
 
 43. If 20 cc. of air are mixed with 30 cc. of H 
 and exploded, what volumes of what gases are left? 
 
 44. What is the difference in mass between 10 1. of 
 air at + 15 C. and 10 1. of N under 775.62 mm. ? 
 
 45. A man inhales 18 ft. 3 of air per hour. How 
 many Ib. of O does he require in 24 hr. ? 
 
 46. What is the mass of 500 m. 3 of air at + 21 C. ? 
 
168 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 47. An inch of rainfall is how many tons of water per 
 acre? 
 
 48. How much moist iron can be oxidized by 1000 1. 
 of air at + 13 C. ? 
 
 49. How much S can be burned in 20 1. of air at + 26 
 C.? 
 
 50. What volume of air at + 21 C. must be passed 
 over 100 g. of Cu to convert it into CuO ? 
 
 51. How much Mg can be burned in a globe contain- 
 ing 5 1. of air at +21 C. and 744 mm. ? 
 
 52. A cubic mile of air at 760 mm. and -f- 30 C. is 
 saturated with water vapor. How many tons of rain 
 will fall if the temperature sinks to C. ? 
 
 53. In one of Lord Rayleigh's experiments, 7925 cc. 
 of air left 65 cc. of argon ; what is the percentage by 
 volume of argon in the atmosphere? 
 
 54. The specific heat of graphite is 0.202; what is 
 its probable atomic weight? 
 
 55. If 4427 million ft. 3 of coal are piled into a cube, 
 find the length of each edge in m. 
 
 56. Find the formula of a substance containing: 
 
 0,20%; 0,26.6%; 8,53.3%. 
 
 57. What volume of air is required to burn a Kg. of 
 carbon ? 
 
 58. If 15.2 1. of methane at -f 17 C. and 870 mm. are 
 required, how much dry sodium acetate must be used? 
 
 59. If 25 cc. of ethene are exploded with 100 cc. of 
 O, what volume of CO 2 is formed and of O is left? 
 
 60. What volume of cyanogen at + 16 C. is given 
 off on heating 5 g. of Hg(CN) 2 ? 
 
SYSTEMATIC REVIEW 169 
 
 61. Find the mass of 295 cc. of camphor (C 10 H 16 O) 
 vapor at + 210 C. 
 
 62. In Meyer's third method, 0.12 g. of dibromamy- 
 lene gave 13.1 cc. of air at + 17 C. and 758 mm. 
 Find the density of the vapor. 
 
 63. How many g. of MnO 2 are required to make 
 40 1. of Cl at + 37 C. ? 
 
 64. What volume of Cl at + 12 C. and 750 mm. 
 can be obtained from 1170 g. of salt? 
 
 65. If 10 g. of K 2 Cr 2 O 7 are heated with HC1, what 
 volume of Cl at + 30 C. and 740 mm. is given off? 
 
 K 2 Cr 2 O 7 + 14 HC1 = 7 H 2 O + 2 KC1 + 2 CrCl 3 + 3 C1 2 . 
 
 66. What volume of Cl will diffuse under the same 
 conditions as 10 cc. of N ? 
 
 67. When 1 g. of bleaching powder was boiled with 
 CuO, it gave 80 cc. of O at + 7 C. and 800 mm. 
 Find the percentage of real bleaching powder in the 
 sample. 
 
 68. What is the mass of 1 1. of chloroform vapor 
 measured at + 200 C. ? 
 
 69. How many cc. does a Ib. of Br (sp. gr. = 3.19) 
 occupy ? 
 
 70. How much P and what volume of Br is required 
 to make 1 1. of HBr ? 
 
 P + 3 Br + 3 H 2 O = H 3 PO 4 + 3 HBr. 
 
 71. Br vapor is 2.8 times as heavy as air ; what is its 
 molecular weight? 
 
 72. If 10 g. of KBrO 3 are heated, what volume of 
 oxygen measured at + 13 C. is given off ? 
 
 73. A spherical glass bulb contains 10 g. of liquid 
 Br (sp. gr. = 3.19) ; what must the internal radius be ? 
 
170 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 74. How much FeCl 3 is required to obtain iodine 
 from 100 tons of kelp, each ton of which contains 4.07 
 Kg. of iodine ? 
 
 2 Nal + 2 FeCl 8 = 2 NaCl + 2 FeCl 2 + I 2 . 
 
 75. How many times is solid iodine (sp. gr. = 4.94) 
 as heavy as an equal volume of its vapor measured at 
 + 350 C. ? 
 
 76. How much iodine is there in a 1. of a solution 
 (sp. gr. = 1.7) containing 52% of HI? 
 
 77. How much iodine and KC1O 3 are required to 
 make 1 Kg. of hydrogen iodate ? 
 
 10 KC1O 3 + 12 I + 6 H 2 O = 10 KC1 + 12 HIO 3 . 
 
 78. If 8 g. of silver iodate are heated, what volume 
 of oxygen at + 18 C. and 720 mm. is evolved? 
 
 79. What volume of HF at + 39 C. can be obtained 
 from 50 g. of NaF? 
 
 80. Find the mass of 10 1. of HF at + 30 C. and 
 740 mm. 
 
 81. What volume is occupied by 1000 g. of (a) 
 common sulphur (sp. gr. = 2.05), (6) plastic sulphur 
 (sp. gr. = 1.95)? 
 
 82. What volume is occupied by 19.2 g. of SO 2 ? 
 
 83. If 16 cc. of H diffuse in 100 sec., what volume 
 of SO 2 will diffuse under the same conditions? 
 
 84. How much iodine is needed to oxidize 1 g. of 
 " hypo," and how much sodium tetrathionate is formed ? 
 
 2 Na 2 S 2 3 , 5 H 2 + T 2 = 2 Nal + 10 H 2 O + Na 2 S 4 O 6 . 
 
 85. SO 3 is passed over 187 g. of BaO in a heated 
 tube ; how much BaSO 4 is formed? 
 
SYSTEMATIC REVIEW 171 
 
 86. How many Kg. of H 2 SO 4 (sp. gr. =1.84) will 
 a tank 1 m. x 2 m. x 3 m. hold ? 
 
 87. If 100 g. of Pb form 146.45 g. of PbSO 4 , what 
 is the molecular weight of H 2 SO 4 ? 
 
 88. If 20 g. of S are heated in H, what volume of 
 H 2 S at + 30 C. is formed? 
 
 89. If 390 g. of Sb 2 S 3 are dissolved in hot HC1, what 
 volume of H 2 S at + 30 C. is given off ? 
 
 90. How many g. of S are there in 600 ec. of H 2 S ? 
 
 91. What volume of H 2 S will diffuse under the same 
 conditions as 10 cc. of oxygen ? 
 
 92. How much PbS and HgS can be thrown down 
 by 500 cc. of H 2 S at + 14 C. ? 
 
 93. What volume of CS 2 (sp. gr. =1.26) can be 
 made by the action of a Kg. of S upon hot charcoal? 
 
 94. What is the mass of 4 1. of carbon oxysulphide 
 (COS) at + 30C. ? 
 
 95. To make 1000 Kg. of H 2 SO 4 , how much pyrite is 
 needed ? What volume of air at + 15 C. and of 
 steam at + 300 C. are required ? 
 
 2 FeS 2 + 4 H 2 + 15 O = Fe 2 O 3 + 4 H 2 SO 4 . 
 
 96. What volume of CS 2 (sp. gr. =1.26) must be 
 burned to give 101. of SO 2 at + 15 C. and 750 mm.? 
 
 97. Boron trichloride is 4.07 times as heavy as air; 
 what is its molecular weight ? 
 
 98. How many g. do 200 cc. of BC1 3 at + 97 C. and 
 720 mm. weigh? 
 
 99. If 90 g. of CaF 2 are heated with B 2 O 3 and 
 H 2 SO 4 , what volume of BF 3 at + 15 C. is formed ? 
 
 3 CaF 2 + B 2 3 + 3 H 2 SO 4 = 3 CaSO 4 + 3 H 2 O + 2 BF 3 . 
 
172 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 100. How much Si can be obtained from 119 g. of 
 K 2 SiF 6 ? K 2 SiF 6 + 4 K = 6 KF + Si. i 
 
 101. How much silica is formed on burning 2 1. of 
 SiH 4 ? 
 
 102. What volume of Cl. at + 26 C. and mass of 
 are required to make 100 g. of SiCl 4 ? 
 
 Si0 2 + 2 C + 2 C1 2 = 2 CO + SiCl 4 . 
 
 103. How much does a 1. of SiCl 4 at + 200C. 
 weigh? 
 
 104. Find the mass in g. of a sphere of quartz 
 (sp. gr. = 2.65) 1 dm. in diameter. 
 
 105. How much bone ash containing 87% of 
 Ca 3 (PO 4 ) 2 is required to make 200 Kg. of superphos- 
 phate of lime? 
 
 Ca 3 (P0 4 ) 2 + 2 H 2 S0 4 = 2 CaSO 4 + CaH 4 (PO 4 ) 2 . 
 
 106. If 100 1. of yellow (sp. gr. = 1.83) are con- 
 verted into red (sp. gr. = 2.16) phosphorus, what is 
 the volume of the latter variety ? 
 
 107. What is the mass of 1.234 1. of P vapor (P 4 ) 
 at + 500 C. ? 
 
 108. If 1 g. of P, when burned, gives 2.29 g. of P 2 O 5 , 
 what is the atomic weight of P? 
 
 109. Find the formula of a substance containing : 
 Ca, 38.72%; P, 20%; O, 41.28%. 
 
 110. If 20 g. of hydrogen metaphosphate are boiled 
 with water, how much orthophosphate is formed ? 
 
 HP0 3 + H 2 = H 3 P0 4 . 
 
 111. If 5 g. of phosphorus are boiled with baryta 
 water, what volume of PH 3 at + 15 C. is given off ? 
 
 2 P 4 + 3 Ba(OH) 2 + 6 H 2 O = 3 Ba (PH 2 O 2 ) 2 + 2 PH 3 . 
 
SYSTEMATIC REVIEW 173 
 
 112. What volume of PH g will diffuse under the 
 same conditions as 100 cc. of hydrogen ? 
 
 113. What volume of Cl at + 20 C. must be passed 
 into 1 Kg. of melted P to convert it into PC1 8 ? 
 
 114. How much P is contained in 4.3 1. of PH 3 meas- 
 ured at + 22 C. and 730 mm. ? 
 
 115. How many g. do 2 1. of As 4 vapor weigh ? 
 
 lie. If 743 cc. of gas are heated from +47 C. to 
 -f- 83 C., what is the new volume ? 
 
 117. What volume do 486 cc. of gas under a pressure 
 of 760 mm. occupy under the pressure of 3 ft. of 
 mercury ? 
 
 118. If 1000 cc. of air at -31.2 R. are heated to 
 + 172.4 F., what is the new volume? 
 
 119. If 546 cc. of gas at + 17 C. and 760 mm. are 
 cooled to C., the pressure being decreased to 600 
 mm., what is the new volume ? 
 
 120. If 1234 cc. of normal gas are cooled to 52 C., 
 the pressure being decreased to 617 mm., what is the 
 new volume ? 
 
 121. A few drops of water at + 15 C. are passed 
 up into a barometer standing at 30 in. How high does 
 the mercury stand ? 
 
 122. If 100 g. pf Sb gave 124.8 g. of Sb 2 O 4 , and if 
 O = 100, what is the atomic weight of Sb ? 
 
 123. Bi melts at + 264 C ; what temperature is 
 this on the F. and R. scales ? 
 
 124. Schneider found that 54.969 g. of Bi formed 
 61.311 g. of the trioxide ; what is the atomic weight 
 of Bi ? 
 
174 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 125. What volume is occupied by 10 g. of trimethyl- 
 stibine Sb(CH 3 ) 3 at + 300 C.? 
 
 126. What is the mass of a sphere of Bi (sp. gr. = 9.9) 
 2 mm. in diameter ? 
 
 127. Find the volume of 100 g. of (a) Pt (sp. gr. 
 = 21.5); (6) Au (sp. gr. =19.3); (c) Pb (sp. gr. 
 = 11.4); (d) Li (sp.gr. = 0.59). 
 
 128. What length of wire 2 mm. in diameter can be 
 drawn from 1 dm. 3 of metal ? 
 
 129. How much platinum black is obtained on boil- 
 ing 40 g. of platinic chloride with grape sugar and 
 sodium carbonate ? 
 
 PtCl 4 + 2 Na 2 C0 3 = 4 NaCl + 2 CO 2 + O 2 + Pt. 
 
 130. If 900 g. of Au (sp. gr. = 19.3) are fused with 
 100 g. of Ag (sp. gr. = 10.5), what is the density of 
 the alloy? 
 
 131. If 5 g. of K 2 O 4 are boiled with water, what vol- 
 ume of O at + 100 C. is evolved ? 
 
 K 2 4 + H 2 = 2 KOH +30. 
 
 132. If 2 g. of hydroxylamine are heated with KOH, 
 what volumes of N and of NH 3 at 4- 21 C. are formed ? 
 
 3 NOH 3 = N 2 + NH 3 + 3 H 2 O. 
 
 133. How much SrO is obtained on heating 1000 g. 
 ofSr(N0 3 ) 2 ? 
 
 134. One g. of CaSO 4 will form how much BaSO 4 ? 
 
 135. How much Al is set free on passing '7. 339 1. of 
 the vapor of A1C1 3 at + 546 C. over heated Na ? 
 
 2 A1C1 3 + 6 Na = 6 NaCl + A1 2 . 
 
 136. How much sulphide is formed on heating 5 g. 
 of Al in S vapor ? 
 
SYSTEMATIC REVIEW 175 
 
 137. If 20 g. of cryolite are heated with H 2 SO 4 , what 
 volume of HF at + 20 C. is given off ? 
 
 2 Na 8 AlF 6 + 6 H 2 SO 4 = 3 Na 2 SO 4 + A1 2 (SO 4 ) 3 + 12 HF. 
 
 138. If 4 g. of dolomite, when strongly heated, gave 
 937.4 cc. of CO 2 , what is the percentage of Ca and 
 MgCO 3 in the dolomite ? 
 
 (CaMg)C0 3 = (CaMg)O + CO 2 . 
 
 139. What volume of N at -h 20 C. and 780 mm. 
 will combine with 50 g. of Mg ? 
 
 140. How much zinc white can be made from 1000 g. 
 of Zn and what volume of air is required ? 
 
 141. Brass consists of 2 parts of Cu alloyed with 
 1 part of Zn ; find the approximate formula for it. 
 
 142. If 100 g. of sodium manganate are heated in 
 steam, what volume of oxygen at -h 13 C. is set free ? 
 
 Na 2 MnO 4 + H 2 O = 2 NaOH + MnO 2 + O. 
 
 143. During the solution of 1 g. of iron, 389.74 cc. 
 of H at + 14 C. and 820 mm. were evolved ; find the 
 equivalent of iron. 
 
 144. According to Berzelius, 1.586 g. of Fe form 
 2.265 g. ferric oxide; what is the atomic weight of 
 iron ? 
 
 145. What volume of CO at + 17 C. is set free on 
 heating 10 g. of diferroheptacarbonyl to + 80 C. ? 
 
 Fe 2 (CO) 7 = Fe + Fe(CO) 5 + 2 CO. 
 
 146. How much S precipitates on passing 1.7 1. of 
 H 2 S at + 17 C. through a solution of FeCl 3 ? 
 
 2 FeCl 3 + H 2 S = 2 FeCL + 2 HC1 + S. 
 
176 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 147. How much Fe is converted from a ferrous to 
 a ferric salt by 1 g. of potassium (a) permanganate ; 
 (5) dichromate ? 
 
 10 FeSO 4 + 2 KMnO 4 + 8 H 2 SO 4 = 
 
 5 Fe 2 (SO 4 ) 3 + K 2 SO 4 + MnSO 4 + 8 H 2 O ; 
 6 FeSO 4 + K 2 Cr 2 O 7 + 7 H 2 SO 4 = 
 
 3 Fe 2 (S0 4 ) 3 + K 2 S0 4 + Cr 2 (SO 4 ) 3 + 7 H 2 O. 
 
 148. If 3 g. of KMnO 4 and K 2 Cr 2 O 7 are each dis- 
 solved in 1 1. of water, to how much Fe is 1 cc. of each 
 solution equivalent ? 
 
 149. What volume of CO at + 1200 C. is set free in 
 reducing 764 g. of nickelous oxide ? 
 
 NiO + C = Ni + CO. 
 
 150. How much HgO is required to precipitate 20 g. 
 of Ni as NiO ? 
 
 NiCl 2 + HgO = HgCl 2 + NiO. 
 
 151. What is the formula of a substance containing : 
 Ni, 31.15%; H, 3.18 %; N, 14.84%; S, 16.95%; 
 O, 33.88%? . 
 
 152. What volume of H at + 15 C. is required to 
 reduce 100 g. of Co 2 O 3 ? 
 
 153. If 100 g. of Hg 2 CrO 4 are heated, how much 
 Cr 2 O 3 is formed and what volume of O is given off? 
 
 2 Hg 2 Cr0 4 = 4 Hg + Cr 2 O 3 + 5 O. 
 
 154. According to Siewert, 36.865 parts of CrCl 3 
 give 100 parts AgCl ; find the atomic weight of chro- 
 mium. 
 
 155. How much (NH 4 ) 2 Cr 2 O 7 can be made from 
 1000 g. of K 2 Cr 2 7 ? 
 
 K 2 Cr 2 7 + H 2 S0 4 = K 2 S0 4 + H 2 O + 2 CrO 3 ; 
 2 Cr0 3 + 2 NH 3 + H 2 O = (NH 4 ) 2 Cr 2 O 7 . 
 
SYSTEMATIC REVIEW 177 
 
 156. According to Berlin, 100 g. of Pb(NO 3 ) 2 gave 
 97.576 g. of PbCrO 4 ; find the atomic weight of chro- 
 mium. 
 
 157. What volume of SO 2 at + 15 C. and 780 mm. 
 is required to reduce 47 g. of K 2 Cr 2 O 7 ? 
 
 K 2 Cr 2 7 + 3S0 2 + H 2 S0 4 = Cr 2 (SO 4 ) 3 + K a SO 4 + H 2 O. 
 
 158. How many times is the vapor of chromyl dichlo- 
 ride (CrO 2 Cl 2 ) as heavy as air ? 
 
 159. If 17 g. of Sn were dissolved in NaOH, what 
 volume of H at -f- 15 C. was evolved ? 
 
 Sn + 2 NaOH + H 2 O = Na 2 SnO 3 + 2 H 2 . 
 
 160. What volume of HC1 at + 60 C. is required to 
 convert 50 g. of Sn into stannous chloride? 
 
 161. What volume of Cl at + 26 C. is absorbed in 
 converting 1000 g. of Sn into the tetrachloride? 
 
 162. What volume of H 2 S at + 26 C. is required to 
 throw down the Sn from a solution of 110 g. of " tin 
 salts"? 
 
 SnCl 2 , 2 H 2 + H 2 S = SnS + 2 HC1 + 2 H 2 O. 
 
 163. If 9 g. of Sn are dissolved in aqua regia, what 
 volume of H 2 S at + 15 C. and 770 mm. is required to 
 precipitate them? 
 
 164. If 4 g. of Sn are heated in 200 cc. of H 2 S at 
 + 10 C. and 744 mm., how much does the Sn increase 
 in mass ? 
 
 165. What volume of air is required to convert 37.1 
 Kg. of Pb into litharge? 
 
 166. How much silica must be fused with 1000 g. of 
 PbO to form lead silicate ? 
 
178 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 167. What volume of O at + 13 C. is absorbed in 
 forming 1000 g. of red lead? 
 
 168. According to Dumas, 100 g. of minium when 
 heated give 2.4 g. of O; find its formula. 
 
 169. Find the percentage composition of realgar, 
 orpiment, and arsenic pentasulphide. 
 
 170. What volume of H 2 S at + 21 C. is required to 
 precipitate the As from a solution of 100 g. of As 2 O 3 ? 
 
 171. The specific heat of As is 0.0814 and 96.15 
 parts of As combine with 3.85 parts of H; find the 
 atomic weight of the element. 
 
 172. How much Sb is there in 1020 Kg. of the tri- 
 sulphide ? 
 
 173. What volume is occupied by 100 g. of (a) As 
 (sp. gr. = 5.8) ; (6) Sb (sp. gr. = 6.8) ; < Bi (sp. gr. = 
 9.9)? 
 
 174. How much lead dioxide can be made from 20 g. 
 of Pb(N0 3 ) 2 ? 
 
 Pb(N0 3 ) 2 + CaOCl 2 + H 2 = 2 HC1 + Ca(NO 3 ) 2 + PbO 2 . 
 
 175. Find the formula of Cassel yellow, which con- 
 tains: Pb, 90.05%; Cl, 3.86%; and O, 6.09%. 
 
 176. PbI 2 is soluble in 190 times its mass of hot water. 
 How much KI and Pb(NO 3 ) 2 must be dissolved in 
 250 cc. of water that the precipitate may redissolve on 
 boiling ? 
 
 177. According to Stas, 100 g. of Pb form 195. 9703 g. 
 of Pb(NO 3 ) 2 ; what is the atomic weight of Pb? 
 
 178. A substance contains of lead monoxide 76.69% 
 and of chromium trioxide 23.31% ; find its formula. 
 
SYSTEMATIC REVIEW 179 
 
 179. What volume of CO 2 at -f 26 C. is evolved on 
 dissolving 487 g. of white lead in hydrogen nitrate? 
 
 Pb(OH) 2 , 2 PbC0 3 + 6 HN0 3 = 
 4H 2 + 3Pb(N0 3 ) 2 + 2C0 2 . 
 
 180. What volume is occupied by the vapor of 4 g. 
 plumbic ethide, Pb(C 2 H 5 ) 4 , measured at + 300 C. and 
 740 mm.? 
 
 181. If 100 g. of CuSO 4 are warmed with KOH and 
 grape sugar, how much cuprous oxide precipitates? 
 
 2 CuSO 4 , 5 H 2 O + 4 KOH = 
 2 K 2 SO 4 + 12 H 2 O + O + Cu 2 O. 
 
 182. What volume of H at + 100 C. and 746 mm. 
 is given off on dissolving 3 g. of cuprous hydride in 
 HC1? 
 
 Cu 2 H 2 + 2 HC1 = Cu 2 Cl 2 + 2 H 2 . 
 
 183. If 8000 g. of cinnabar are roasted, how much 
 Hg and what volume of SO 2 at + 13 C. are formed? 
 
 184. Hg vapor is 6.976 times as heavy as air; find 
 its density referred to H. 
 
 185. When 1 Kg of Hg at -f 100 C. is mixed with 
 1 Kg of water at -f 10 C., the temperature of the 
 mixture was found to be + 13 C.; what is the specific 
 heat of Hg? 
 
 186. Find the formula of a cadmium amalgam which 
 contains : Hg, 78.26 %, and Cd, 21.74%. 
 
 187. Excess of Hg is heated in 10 1. of air measured 
 at + 14 C. ; how much HgO is formed ? 
 
 188. The vapor of Hg 2 Cl 2 is 8.21 times as heavy as 
 air; what is its apparent molecular weight? 
 
 189. How many g. do 500 cc. of the vapor of corro- 
 sive sublimate at -h 350 C. weigh? 
 
180 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 190. How much Fe and Hg are required to reduce 
 48 Ib. of AgCl? 
 
 191. Melted Ag dissolves 22 times its volume of 
 oxygen at C. What volume of O at + 13 C. would 
 be given off by 1 Kg. of Ag (sp. gr. = 10.5) on cool- 
 ing? 
 
 192. According to Stas, 53.1958 g. of Ag form 
 92.6042 g. of AgBr; what is the atomic weight of 
 silver ? 
 
 193. What volume of H 2 S at + 27 C. and 570 mm. 
 is required to precipitate the Ag from 100 g. of silver 
 metaphosphate ? 
 
 2 AgP0 8 + H 2 S = Ag 2 S + 2 HP0 3 . 
 
 194. How much FeSO 4 is required to precipitate 
 100 g. of Au? 
 
 6 FeS0 4 , 7 H 2 + 2 AuCl 3 = 
 4 Fe 2 (SO 4 ) 3 + 42 H 2 O + 2 FeCl 3 + 2 Au. 
 
 195. How much magnesia is required to throw down 
 10 g. of auric oxide ? 
 
 2 AuCl 3 + 3 MgO = 3 MgCl 2 + Au 2 O 3 . 
 
 196. What volume of O is given off on heating 
 4.412 g. of Au 2 O 3 ? 
 
 197. Prat has described an oxide of gold containing 
 7.7% of oxygen; find its formula. 
 
 198. How much aurous bromide can be made from 
 2 g. of Au 2 O ? 
 
 199. If 50 g. of auric chloride are heated to + 170 C., 
 how much aurous chloride and what volume of Cl 
 measured at + 21 C. are formed? 
 
 AuCL = AuCl + CL. 
 
SYSTEMATIC REVIEW 181 
 
 200. A solution of 10 g. of AuCl 3 is mixed with hy- 
 drogen oxalate ; how much Au precipitates and what 
 volume of CO 2 at + 13 C. is given off? 
 
 2 AuCl 3 + 3 H 2 C 2 O 4 = 2 Au + 6 HC1 + 6 CO 2 . 
 
 201. How much spongy platinum is left on heating 
 100 g. (NH 4 ) 2 Pt01 8 ? 
 
 202. How much PtCl 4 is obtained on dissolving 500 g. 
 of Pt in aqua regia? 
 
 203. How much platinous hydrate is formed on di- 
 gesting 200 g. of platinous chloride with KOH? 
 
 PtCl 2 + 2 KOH = 2 KC1 + Pt(OH) 2 . 
 
 204. According to Berzelius, 10 g. of Pt form 
 24.735 g. of K 2 PtCl 6 ; find the atomic weight of 
 platinum. 
 
 MISCELLANEOUS REVIEW 
 
 205. How much CaO and how much coke are 
 needed to produce 100 Ib. of CaC 2 ? 
 
 206. How much chrome-alum could be made from 
 10 Kg. of chromite? 
 
 207. What weight of chrome-yellow would be formed 
 if a solution containing 430 g. of K 2 CrO 4 were precipi- 
 tated with lead acetate ? 
 
 208. What weight of KMnO 4 could be prepared from 
 10 Kg. of an ore containing 62 % pyrolusite ? 
 
 209. Find the percentage composition of nitric acid. 
 How many g. of each component in 150 g. of nitric 
 acid? 
 
 210. Find the percentage composition of H 2 SO 4 . 
 How many g. of HC1 can be formed by the action of 
 490 g. of H 2 SO 4 onNaCl? 
 
182 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 211. Find the percentage composition of H 2 S. How 
 many g. of H 2 S can be made by the action of 146 g. of 
 HC1 on ferrous sulphide? 
 
 212. A mixture of 30 cc. of air and 40 cc. of hy- 
 drogen is introduced into a eudiometer tube and the 
 mixture ignited by an electric spark. The gas remain- 
 ing in the tube after the explosion measures 51.1 cc. 
 What per cent, by volume of oxygen is contained in 
 the air used, assuming that the gases are all measured 
 at the same temperature? 
 
 213. A candle of paraffine (C, 85 % ; H, 15 % ) loses 
 90 g. in weight by burning ; find the weights and 
 volumes of the products of combustion and of oxygen 
 used. 
 
 214. What weight of phosphorus would be needed to 
 combine with 700 cc. of oxygen to form phosphorus 
 pentoxide? 
 
 215. If 1 g. of hydrogen and 1 g. of oxygen are 
 mixed and the mixture is ignited, what weight of water 
 will be formed and what volume of gas will remain 
 uncombined ? 
 
 216. What weight of oxygen will unite to form water 
 with a volume of hydrogen that measures 1250 cc. at 
 740mm. and +18C.? 
 
 N 217. A certain analysis gives 42.1% of carbon, 7.1 % 
 of hydrogen, 56.2% of oxygen, (a) Find a formula 
 for the compound. (5) It being hexabasic, give the 
 true formula. (<?) All the hydrogen can be replaced by 
 a metal. To what class of compounds does it belong? 
 218. Reduce the following to the Fahrenheit scale : 
 (a) +35C. ; (5) + 89 C. ; <V) -40 C. ; (d) -50 
 C. ; 0) + 104 C. 
 
SYSTEMATIC REVIEW 183 
 
 219. If a given weight of gas occupies 1.1 1. at C. 
 and 380 mm., what volume should it occupy at + 273 
 C. and 760 mm. ? 
 
 220. Reduce the following to ft. 3 or in. 3 : (a) 1.5 1. ; 
 (6) 760 cc. ; (c) 7 m. 3 ; (d) 85 dm. 3 ; < 900 cc. ; 
 (/) 1.2 cc. 
 
 221. If water absorbs 1000 times its volume of am- 
 monia, how many g. of ammonium chloride will furnish 
 enough gas for 2 1. of water ? 
 
 222. How many g. of coin silver, which is T 9 ^ pure, 
 will make 50 g. of bromide of silver for photog- 
 raphy ? 
 
 223. Prove that the phosphorus molecule has 4 atoms. 
 
 224. A m. 3 of carbon monoxide burns in air. (a) Find 
 the number of cc. of carbon dioxide which will form at 
 N.T.P. (5) Find approximately the number of ft. 3 
 
 225. A cube of sulphur (sp. gr. = 2) is 2| cm. on a 
 side ; how much SO 2 , by weight and by volume, will 
 form on burning it ? 
 
 226. By using 100 tons of FeS 2 there were obtained 
 136.3 tons of H 2 SO 4 . If there were no waste, what per 
 cent, of sulphur does the pyrite carry ? What per cent, 
 does pure FeS 2 carry ? 
 
 227. A mixture of | hydrogen by volume and J arsine, 
 5 1. in all, is burned, (a) What weight of water is 
 formed ? () What volume would the arsenic occupy 
 at -f 273 C. if it could be set free as a gas ? 
 
 228. H 2 SO 4 has sp. gr. =1.84; what volume of sul- 
 phur dioxide at + 200 C. and 700 mm. will be given by 
 30 cc. of it reduced by copper ? 
 
184 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 229. What volume of hydrogen is required to combine 
 with the oxygen in 12 g. of nitrous oxide ? 
 
 230. Water will absorb 1050 times its volume of am- 
 monia gas ; how many g. of ammonium chloride will 
 be required to furnish the gas sufficient to saturate 500 
 cc. of water ? 
 
 231. If 10 1. of hydrogen diffuse through a certain 
 apparatus in a certain time, what volume of hydrogen 
 phosphide will diffuse under similar conditions ? 
 
 232. Compute the vapor density (a) of ozone from 
 the atomic weight of oxygen and the fact of there being 
 
 3 atoms in the molecule of ozone ; (5) of arsenic with 
 
 4 atoms per molecule ; (<?) of zinc, which has 1 atom per 
 molecule. 
 
 233. A block of lead (sp. gr. = 11.4) 5x2x2 cm. 
 is dissolved by HNO 3 ; how much NO by volume ought 
 to be liberated ? 
 
 234. How much CaCO 3 by weight should be formed 
 by introducing into lime water the carbon dioxide formed 
 in burning 500 cc. of liquid ether having sp. gr. = 
 0.72? 
 
 235. How much phosphorus by weight can be burned 
 in 5 1. of nitrogen monoxide ? 
 
 236. How much H 2 S by volume will be formed by the 
 action on FeS of 1 1. of HC1 solution which has sp. 
 gr. = 1.2 and contains 43% HC1 gas ? 
 
 237. A substance analyzed gives 20% water, 26.66% 
 carbon, 53.13% oxygen; find its formula. 
 
 238. How much chlorine in a 1. of water, 20 cc. of 
 which will precipitate all the silver in 0.02 g. of silver 
 nitrate ? 
 
SYSTEMATIC REVIEW 185 
 
 239. If 2 Kg. of coal produce in burning 6 Kg. of CO 2 
 and 900 g. of water, what percentage of carbon and of 
 hydrogen does the coal contain ? 
 
 240. One g. of an aqueous solution of hydrogen 
 chloride (sp. gr. = 1.20) contains how many cc. of 
 hydrogen chloride ? 
 
 241. How many Kg. in 3 m. 3 of sulphuric acid (sp. 
 
 242. What volume would be occupied by 2 cc. of sul- 
 phuric ether (sp. gr. = 0.72) if it were vaporized at 
 + 270 C. and 750 mm. ? 
 
 243. Reduce the following to C. : (a) + 38 F. ; 
 (6) + 120 F. ; (<0 -64 F. ; (d) - 30 F. ; (e) F. ; 
 
 244. If equal volumes of hydrogen and oxygen are 
 mixed in a closed space at a temperature above the 
 boiling point of water, and the mixture is exploded, 
 what will be the pressure of the products compared 
 with the original pressure at the same temperature ? 
 
 245. When 37.4 g. of nickel oxide were heated in a 
 current of hydrogen they lost in weight 8.000 g. The 
 specific heat of nickel is 0.109. What information do 
 these data give concerning the atomic weight of nickel ? 
 
 246. Write the equations representing the volume 
 relations, (a) when carbon monoxide burns in oxygen ; 
 (5) when ammonia gas is decomposed into its elements. 
 Give the relative numbers of molecules taking part in 
 each reaction . 
 
 247. What volume is occupied by 80 g. of ammonia 
 (a) at N.T.P.; (b) at +273 C. and pressure of 2 
 atmospheres ? 
 
186 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 248. How much ammonium chloride must be heated 
 with lime to make 50 1. of ammonia at N.T.P. ? 
 
 249. Write equations for (a) the action which takes 
 place on boiling water hardened by carbonate of mag- 
 nesium in solution ; (6) the preparation of peroxide of 
 hydrogen; (<?) the action of carbonic acid on barium 
 hydrate. 
 
 250. How much zinc sulphate can be made from 
 20 Ib. of zinc ? 
 
 251. If 3 1. of a gas consisting of carbon and oxygen 
 weigh 3.78 g., what is the formula of the gas ? 
 
 252. Compare the diffusibilities of these gases, carry- 
 ing the answer to one decimal place : (a) N 2 O and CO ; 
 (5) Br and Cl; < N and NH 3 ; (d) NO and H; 
 <Y) CO and CO 2 ; (/) CH 4 and HC1; (#) C 2 H 6 O and 
 (C 2 H 5 ) 2 O; (A) H 2 S and CS 2 ; (i) H and H 2 S. 
 
 253. A gas, A, diffuses 3.5 times faster than B\ if 
 the molecular weight of A is 4, what is that of B ? 
 
 254. Two gases, A and J5, diffuse approximately at 
 6.1:4.1; if A has a molecular weight of 34, what 
 should be that of B ? 
 
 255. If 3 1. of nitrous oxide weigh 5.94 g., what is 
 its vapor density ? 
 
 256. What is the weight of 1239 1. of phosphorus 
 vapor at +21 C. ? 
 
 257. A manufacturer prepares phosphorus from 169 
 tons of bones, containing 55 % of calcium phosphate ; 
 how much phosphorus should he obtain and how much 
 oil of vitriol ought he to use ? 
 
 258. How much chlorine by volume can be got from 
 10 g. of NaCl? 
 
SYSTEMATIC REVIEW 187 
 
 259. If 5 1. of turpentine vapor are burned in air, 
 () what are the products ; (b) what is the volume of 
 the compound of carbon formed at C. and 760 mm. ? 
 
 260. Excess of carbon is thrown into 100 g. of fused 
 niter; what volume of N and of CO 2 is evolved? 
 
 4 KNO 3 + 5 C = 2 K 2 CO 3 + 4 N + 3 CO 2 
 
 261. If the density of marsh gas is 0.55 and its per- 
 centage composition is carbon, 74.95, and hydrogen, 
 25.05, prove that the atomic weight of carbon is not 
 more than 12. 
 
 262. Prove that the molecule of oxygen has at least 
 
 2 atoms. 
 
 263. How many cc. of liquid water are contained in 
 a rectangular piece of gypsum (sp. gr. = 2.3) which is 
 
 3 cm. x 5 cm. x 7 cm. ? How much SO 2 is contained 
 in it? 
 
 264. When 7 cc. of sulphur vapor and 5 cc. of oxygen 
 combine, so far as possible, to form SO 2 , how many 
 cc. of SO 2 are formed and how much of either factor is 
 left? 
 
 265. A cube of crystallized NaCO 3x 10 H 2 O (sp. gr. = 
 1.45) is 6 cm. on a side, (#) What volume, as a 
 liquid, would the water of crystallization occupy ? 
 () What volume would the gaseous CO 2 obtainable 
 from the salt at N.T.P. occupy ? 
 
 266. (a) How much sulphur by weight is required 
 to make 1000 g. of H 2 SO 4 ? (5) If the sp. gr. of 
 H 2 SO 4 is 1.84, how many 1. would the acid occupy ? 
 
 267. How much SO 2 by volume could be obtained by 
 acting with H 2 SO 4 on a plate of copper (sp. gr. = 8.85) 
 which is 5 cm. x 8 cm. x 10 cm. ? 
 
188 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 268. A certain volume of gas at 740 mm. and -J- 30 C. 
 weighs 5 g. ; what would an equal volume of the same 
 gas weigh at 760 mm. and C. ? 
 
 269. Of two gases, A and B, A diffuses twice as rap- 
 idly as B ; compare their molecular weights. 
 
 270. Uranium is the metal having the greatest 
 atomic weight, 238.5; compute its specific heat from 
 the atomic heat. 
 
 271. GASEOUS COMPOUNDS ANALYSES SP. GR. 
 
 HX H:X=1:3 0.557 
 
 OX O:X = 8:3 1.529 
 
 HNX H:N:X = 2:28:24 0.948 
 
 In the above table we have gaseous compounds of an 
 element X. The analyses of the compounds are given, 
 also the sp. gr., air being unity. Air is 14.4 as heavy 
 as hydrogen. What is the atomic weight of the ele- 
 ment X ? Give reasons. 
 
 272. How many 1. of HC1 at + 273 C. and 760 mm. 
 could be obtained by treating with H 2 SO 4 a cube of 
 rock salt (sp. gr. = 2.13) which measures 5.5 cm. on 
 a side ? 
 
 273. How many 1. of hydrogen would be needed to 
 combine with all the oxygen in 50 g. of mercuric oxide ? 
 
 274. If 4 1. of hydrogen diffuse through an apparatus 
 in 10 minutes, and 1 1. of oxygen in an equal time under 
 similar conditions, what is the density of oxygen? 
 
 275. (a) How many cc. of oxygen at +33 C. are 
 needed to burn 175 cc. of benzene vapor? (5) What 
 would be formed? (<?) What weight of CO 2 ? 
 
 276. I wish to make 30 g. of potassium chloride; 
 how much potassium chlorate ought I to take ? 
 
SYSTEMATIC REVIEW 189 
 
 277. Assume that in burning all 2240 Ib. of a certain 
 soft coal in gas retorts, 6 Ib. of ammonia gas are liber- 
 ated and collected in the ammoriiacal liquor ; that 5 % is 
 lost in the transportation and working of the liquor ; 
 that it is made into ammonium sulphate. How much 
 dry sulphate of ammonium will it yield, and how much 
 pure sulphuric acid will be used in the operation, 
 assuming no waste of acid ? 
 
 278. What volume at + 20 C. and under a pressure 
 of 2 atmospheres will 100 1. of sulphur dioxide, meas- 
 ured at 0C. and under a pressure of 1 atmosphere, 
 occupy ? What weight of sulphur is necessary to pro- 
 duce this amount of sulphur dioxide ? 
 
 279. If the combustion of 1 g. of sulphur to sulphur 
 dioxide develops 2220 calories, what is the heat of com- 
 bustion of sulphur ? 
 
 280. Calculate the number of m. 3 of air at + 20 C. 
 needed for one Kg. of coal, the composition of which is : 
 carbon, 76.81%; hydrogen, 5.14%; oxygen, 7.90%; 
 nitrogen, 1.62 % ; sulphur, 1.13 % ; water, 1.70 % ; ash, 
 6.65 %. Assume the factor for excess as 3. 
 
 281. If 1 volume of water at -f 20 C. absorb 650 
 volumes of NH 3 , what weight of ammonia will be 
 taken up by 1 1. of water at the same temperature ? 
 
 282. What weight of NaOH will neutralize 100 1. of 
 HC1? 
 
 283. At C. 1 volume of water will absorb 500 
 times its own volume of HC1. How much will 500 g. 
 of water at increase in weight by absorbing all the 
 HClitcan? 
 
 284. What weight of HC1 can be obtained from 25 g. 
 of salt ? How much Na 2 SO 4 is formed ? 
 
190 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 285. A silver coin containing 8 % of copper weighs 
 2.43 g. If the coin is dissolved in HNO 3 , how many 
 g. of NaCl will be needed to precipitate all the silver 
 as AgCl ? 
 
 In the above, what weight of iron will be required to 
 reduce the AgCl to metallic silver and what will be 
 the weight of the silver obtained ? 
 
 286. How many tons of pure hematite would be 
 needed for the production of 100 tons of iron in the 
 blast furnace, assuming that 2.3% of the iron in the 
 ore passes into slag ? 
 
 287. How much coke would be needed to reduce 50 
 tons of pure hematite ? 
 
 288. An ore contains 36.4 % of " Ruby Copper " 
 (Cu 2 O). With what weight of charcoal must 10 tons 
 be heated to reduce all the Cu 2 O to metallic copper ? 
 
 (Cu 2 O + C = 2 Cu + CO.) ' Find weight of copper. 
 
 289. How much potassium hydroxide will react with 
 20 g. of chlorine, in the formation of potassium chlorate ? 
 
 290. How much potassium hydroxide must be used 
 to obtain 5.0 g. of potassium chlorate ? 
 
 291. How much sodium hydroxide will neutralize 
 10 g. of nitric acid ? 
 
 292. How much sulphuric acid will be neutralized by 
 20 g. of potassium hydroxide ? 
 
 293. How much hydrochloric acid will neutralize 25 
 g. of sodium hydroxide ? 
 
 294. If 40 cc. of a solution of potassium hydroxide 
 are neutralized by 25 cc. of a solution of hydrochloric 
 acid containing 0.001 g. of the acid per cc., what weight 
 of the hydroxide is contained in 10 cc. of its solution ? 
 
SYSTEMATIC REVIEW 191 
 
 295. If 50 cc. of a solution of nitric acid are neutral- 
 ized by 70 cc. of a solution of sodium hydroxide con- 
 taining 0.004 g. of the alkali per cc., what weight of 
 the acid is contained in | 1. of its solution ? 
 
 296. If 25 cc. of a solution of potassium hydroxide 
 are neutralized by 45 cc. of a solution of sulphuric 
 acid containing 0.002 g. of the acid per cc., what 
 weight of the hydroxide is contained in one 1. of its 
 solution ? 
 
 297. How much ammonia gas can be obtained -from 
 40 g. of ammonium chloride ? 
 
 298. How much ammonia is necessary for the produc- 
 tion of 20 g. of ammonium nitrate ? 
 
 299. What weight of nitrogen will appear when 100 
 g. of chlorine are taken up in the decomposition of 
 ammonia ? 
 
 300. How much nitrous anhydride is obtainable from 
 60 g. of potassium nitrite ? 
 
 301. Calculate the weight of a 1. of nitric oxide 
 under standard conditions. 
 
 302. What is the weight of a 1. of hydrocyanide under 
 standard conditions ? 
 
 303. A 1. of gas under 700 mm. pressure at + 40 C. 
 weighs 1.307 g. ; what is its molecular weight? 
 
 304. Five 1. of a gas under 2 atmospheres pressure at 
 4- 50 C. weigh 10.6 g. ; what is the molecular weight 
 of the gas ? 
 
 305. Seven 1. of sulphur dioxide, at + 90 C., are 
 produced by burning 12 g. of sulphur in oxygen ; what 
 is the pressure of the gas ? 
 
192 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 306. The oxygen obtained from 100 g. of potassium 
 chlorate occupies 30 1. under the pressure of 70 cm. of 
 mercury ; what is the temperature of the gas ? 
 
 307. What volume of carbon dioxide at + 20 C. and 
 740 mm. pressure would be produced by the explosion 
 of 10 g. of gunpowder (supposing gunpowder to be 
 2 KNO 3 + 3 C + S) according to the equation 
 
 2 KN0 3 + 3 C + S = 3 C0 2 + N 2 + K 2 S ? 
 
 308. What volume of nitrous oxide, at -f- 30 C. and 
 800 mm. pressure, is obtainable from 100 g. of ammo- 
 nium nitrate ? 
 
 309. How many 1. of hydrogen will result from the 
 electrolysis of 50 g. of water, when the gas is collected 
 over mercury, the level within the tube being 90 mm. 
 above that without, and the temperature and barometric 
 pressure being + 23 C. and 745 mm. respectively ? 
 
 310. How many g. of water may be obtained by burn- 
 ing a quantity of hydrogen occupying 400 1. at 4- 50 C. 
 and 600 mm. pressure ? 
 
 311. Ten 1. of a compound weigh 19.8 g. If T 8 T of it 
 is oxygen and the remainder carbon, find its formula. 
 
 312. What will be the volume of a gas at 760 mm. 
 pressure and + 60 C., which is 2 1. at 380 mm. and 
 + 90 C. ? 
 
 313. If 70 cc. of nitrous oxide should break up, what 
 would be the weight of each constituent ? 
 
 314. A mixture of lead sulphate and barium sulphate 
 weighed 4 g. and analysis of the mixture gave 1.62 g. 
 of SO 4 ; what are the weights of lead sulphate and barium 
 sulphate present in the mixture ? 
 
 
SYSTEMATIC REVIEW 193 
 
 315. A mixture of the acid sulphates of sodium and 
 potassium weighs 0.5 g., and analysis of the mixture 
 shows 0.395 g. of SO 4 ; what weights of sodium and of 
 potassium are contained in the mixture ? 
 
 316. A mixture of acid and neutral potassium car- 
 bonates weighs 1 g., and contains 0.4 g. of carbon diox- 
 ide ; what is the weight of each carbonate ? 
 
 317. A sample of pure dolomite weighs 1 g. and 
 yields 0.48 g. of carbon dioxide ; what weights of cal- 
 cium oxide and of magnesium oxide does it contain ? 
 
 318. Which is the more economical oxidizing agent, 
 potassium nitrate at 5 cts. a Ib. or sodium nitrate at 
 5| cts. a Ib. ? 
 
 319. Which is more economical for neutralizing an 
 alkali, 60 % nitric acid at 6 cts. a Ib. or 30 % HC1 at 
 3 cts. a Ib. ? 
 
 320. Which is the most economical for making car- 
 bon dioxide, sodium dicarbonate at 3 cts. a Ib., sodium 
 carbonate crystallized at 2J cts. a Ib., or calcium car- 
 bonate (marble) at 1 ct. a Ib. ? 
 
 321. Which is the more economical for the prepara- 
 tion of anhydrous ammonia, ammonium sulphate at 8 
 cts. a Ib. or ammonium chloride at 11 cts. a Ib. ? 
 
 322. Which is the more economical oxidizing agent, 
 potassium chlorate at 8 cts. a Ib. or sodium chlorate 
 at 10 cts. a Ib. ? 
 
 323. Given two iron ores, one a lake ore containing 
 62 / of iron and the other an ore containing 45 % of 
 iron, how much of each must be used to give 100 tons 
 of mixture containing 53 % of iron ? 
 
194 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 324. Suppose we wish to form 100 tons of a mixture 
 of ores containing 10 % of copper, and we have at our 
 disposal lots containing 7 % and 18 % respectively ; 
 how many tons of each must be taken ? 
 
 325. Given two iron ores, one containing 0.52% of 
 phosphorus and the other 0.14%, how much of each 
 must be mixed to give 20 tons (2240 Ib. to the ton) 
 containing 0.22% of phosphorus? 
 
 326. Given lead ores containing 60 % and 25 % of 
 lead respectively, how many Ibs. of each must be 
 mixed to give 5000 Ib. containing 45 % of lead ? 
 
 327. Suppose we have 10 tons of coal containing 
 2.5% of sulphur. We have also supplies of coal con- 
 taining 0.80% and 1.10% of sulphur. How much of 
 each shall we add to the 10 tons to make 20 tons con- 
 taining 1.80 % of sulphur ? 
 
 328. Coal contains about 2 % of nitrogen. Assuming 
 that 75 % of this amount escapes as ammonia on distilla- 
 tion, calculate the amount of coal required to furnish 
 the sal-ammoniac needed to produce 10 Kg. of NH 4 OH. 
 
 329. If 100 volumes of Manchester cannel gas con- 
 tained 4.98 volumes of olefines which yielded on com- 
 bustion 13.93 volumes of carbon dioxide, what were 
 the volumes of C 2 H 4 and C 4 H 8 contained in the gas ? 
 
 330. One ft. 3 of hydriodic acid is decomposed by 
 an excess of bromine ; how many ft. 3 of hydrobromic 
 acid are formed ? 
 
 331. If 5 1. of chlorine are mixed with 5 1. of carbon 
 monoxide, what volume of phosgene gas is produced, 
 and how much hydrochloric acid and carbon dioxide 
 would be produced by the decomposition of this gas 
 with water ? 
 
SYSTEMATIC REVIEW 195 
 
 332. How many g. of water at C. would be frozen 
 by the removal of the heat required to evaporate 50 g. 
 of liquid ammonia ? 
 
 333. Find the density of the gas the formula of 
 which is N 2 O 5 . Find the weight of a 1. of phosphine. 
 
 334. Calculate the volume of hydrochloric acid solu- 
 tion (density 1.10 and 20.9% pure acid) that is re- 
 quired to make 500 g. of barium chloride from the 
 carbonate. 
 
 335. What volume of air containing 21 % of oxygen 
 by volume is required to burn 248 g. of phosphorus ? 
 
 336. If 25.82 1. of nitric oxide diffuse through a 
 certain apparatus in 50 minutes, what volume of hydro- 
 gen will diffuse under the same conditions ? 
 
 337. How many g. of sodium chloride dissolved in a 
 1. of water would be required to elevate the boiling 
 point of the solution 0.52 C. ? 
 
 338. How much white lead should be obtained theo- 
 retically from 65 Kg. of lead ? 
 
 339. How much air would be necessary to change 
 6 1. of nitrogen dioxide into the trioxide? (Consider 
 all measurements at C. and 760 mm.) 
 
 340. Suppose we had a bar of aluminum weighing 
 1800 g., how many cc. of water would it displace ? 
 
 341. How much sodium nitrate (98% pure) would 
 have to be present in a fertilizer that contained 4 % of 
 nitrogen, assuming that all the nitrogen came from the 
 nitrate ? 
 
 342. How many g. of KI dissolved in a 1. of water 
 are necessary to lower the freezing point of the solu- 
 tion + 1.86 C. ? 
 
196 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 343. Find the density of the gas having the formula 
 N 2 . 
 
 344. Find the weight of a 1. of hydrogen chloride. 
 
 345. One 1. of gas weighs 0.09 g. ; find its molecular 
 weight. What is this gas ? 
 
 346. How much sodium would be necessary, assum- 
 ing exact proportions, to produce 3 Kg. of aluminum 
 from 2 A1C1 3 , 2 NaCl ? 
 
 347. How many cc. of a solution of potassium per- 
 manganate which contains 40 g. to the 1. would be 
 necessary to oxidize 0.5 g. of iron from the ferrous to 
 the ferric condition ? 
 
 348. How much aluminum should we theoretically 
 obtain from an ore containing 90 % of bauxite ? 
 
 349. If 500 g. of sulphur containing 17% impurities 
 are burned in air, what weight of oxygen is needed ? 
 
 350. If 2 g. of gunpowder produce 600 cc. of gas 
 at C., what is the volume at + 2500 C. ? 
 
 351. What weight of carbon is contained in (V) 1 1. 
 CO ; (5)1 1. CO 2 ; (<?) 1 1. C 2 H 2 ; (d) 1 1. CH 4 ; () 1 1. 
 C 2 H 4 ? 
 
 352. The velocity of diffusion of nitrogen is 1.0143; 
 how many atoms of nitrogen are there in a molecule ? 
 
 353. The velocity of diffusion of oxygen is 0.9487; 
 how many atoms of oxygen are there in a molecule ? 
 
 354. If 25 cc. of dilute H 2 SO 4 required 2.44 g. 
 BaCl 2 , 2 H 2 O for complete precipitation, what percent- 
 age of water was present in the dilute acid ? 
 
 355. How much H 2 SO 4 is needed to decompose 27 g. 
 of common salt ? 
 
SYSTEMATIC REVIEW 197 
 
 356. What is the weight of 40 1. of NH 3 at C. and 
 760 mm. ? If 40 1. of HC1 are mixed with it, what is 
 the weight of the residue ? 
 
 357. If 20 g. oxalic acid are warmed with H 2 SO 4 , how 
 much CaCO 3 can be produced by passing the products 
 through lime water and what volume of gas passes 
 over? 
 
 358. If 130 g. of NH 3 burn, what are the weights of the 
 products of combustion ? 
 
 359. Calculate the effect of adding 2 volumes of a 
 saturated (3.90 molar) solution of potassium chloride 
 to a saturated (0.52 molar) solution of potassium 
 chlorate. Assume that 1.95 molar KC1 is 0.71 ionized. 
 
 360. The sum of the readings of the same temperature 
 on the F. and C. scale is 172 ; what is the reading on 
 each ? 
 
 361. A sample of carbon containing 85 % of carbon 
 and 3% of hydrogen is burned; what volume of air 
 containing 21 % of oxygen is used ? 
 
 362. What weight and volume of air contain 1 g. 
 of nitrogen ? 
 
 363. What volume of chlorine acting on NH 3 will 
 give 10 1. of nitrogen ? 
 
 364. Give the sum and the difference in weight of 20 
 1. of nitrogen and 20 1. of air. 
 
 365. To give 6 1. of PH 3 , how much zinc must be 
 treated with sulphuric acid to give the required amount 
 of hydrogen ? 
 
 366. If 13 g. As 2 S 3 have been thrown down in a 
 solution by the passage of H 2 S, what volume of H 2 S 
 at + 16 C. and 761 mm. was used ? 
 
198 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 367. How much As 2 O 3 corresponds to 12 g. of As 2 S 3 ? 
 
 368. If 1.311 g. of As 2 S 3 were obtained as a result of 
 the analysis of the stomach in a poison case, how much 
 paris green was swallowed ? 
 
 369. To produce 20 g. P 2 O 5 , how much (a) phos- 
 phorus and how much (b) PH 3 must be burned? 
 
 370. One g. of hydrogen is passed over 100 g. of 
 CuO ; find weight of H 2 O and the loss of the CuO. 
 
 371. How many oz. of gold per ton are represented 
 by 40 parts to the million? What would be the value 
 of such ore, rating gold at $20.00 per oz.? 
 
 372. From the following data calculate the weight in 
 Kg. of each constituent of the air in a room 12' 0" x 
 15' 0" x 9' 0" : Composition of the air by volume : 
 nitrogen, 77.35%; oxygen, 20.77%; argon, 0.94%; 
 water vapor, 0.90% ; carbon dioxide, 0.03% ; a 1. of air 
 of above composition weighing 1.29 g. 
 
 373. From the following data calculate the weight in 
 Kg. of each constituent of the air in a room 12' x 15' x 
 9' : assume water vapor = 0.90 % and carbon dioxide = 
 0.03%. 
 
 374. The sp. gr. of zinc is 7.2. A block of it 
 2 cm. x 3 cm. x 4 cm. is dissolved in HC1. How much 
 hydrogen (a) by weight and (5) by volume is evolved? 
 
 375. A block of charcoal -^ pure is 5 cm. x 6 cm. 
 X 7 cm., and has sp. gr. = 1.5 ; how much CO 2 by vol- 
 ume ought to form in burning it? 
 
 376. If PbCO 3 has a sp. gr. = 6.46, how much CO 2 
 by volume could be obtained from a cubical mass of it, 
 7 cm. on a side? 
 
SYSTEMATIC REVIEW 199 
 
 377. At 60 cents per oz., what is the value of the 
 silver in ^ Ib. of silver nitrate ? 
 
 378. If a skeleton weighs 21 Ib. and is 56 % 
 Ca 3 (PO 4 ) 2 , how many matches can be tipped with the 
 phosphorus it contains, if 1 Ib. of phosphorus serves to 
 tip a million matches ? 
 
 379. How much iron is present in a solution which 
 
 M 
 
 requires 47 cc. of a solution of KMnO 4 to produce a 
 
 pink color? 
 
 380. If 5.24 g. coke on burning give 17.54 g. of 
 CO 2 , what is the percentage of carbon in the coke? 
 
 381. If 2 g. were lost by heating a piece of Iceland 
 spar, what weight and volume of CO 2 were produced at 
 + 13C. and 700mm.? 
 
 382. How much HF by volume is needed to reduce 
 the weight of a piece of glass 3 g.? 
 
 383. If 300 tons carbon (87 % pure) are burned in 
 air, how much oxygen is needed ? What volume of gas 
 is produced at - 6 C. and 721 mm.? 
 
 384. What volume of gas is given by 1 g. of "black 
 lead" on complete combustion at standard conditions? 
 
 385. If 12.1764 1. of nitrogen diffuse through a po- 
 rous plate in the time that it takes 9.7044 1. of CO 2 to 
 do so, what is the density of CO 2 compared with air? 
 
 386. If 300 1. of nitrogen dioxide diffuse through a 
 porous plate in 1 hour, what volume of silicon tetra- 
 fluoride will diffuse through in the same time ? 
 
 387. The sp. gr. of bromine is 3.18 ; find the volume 
 of vapor given off when measured at + 90 C. 
 
200 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 388. How much H 2 SO 4 will 20 g. of SO 3 dissolved in 
 water yield? 
 
 389. If 60 1. of nitrogen tetroxide diffuse through a 
 porous, plate in 1 hour, what volume of chlorine tet- 
 roxide will diffuse through in the same time ? 
 
 390. How many g. of MnO 2 and how many cc. of a 
 solution of HC1 (containing 20 % of HC1) are necessary 
 to evolve 1.86 1. of chlorine at C. and 760 mm. ? 
 
 391. How much water will be formed by the action 
 of (a) copper upon 98 g. of hot hydrogen sulphate ; 
 (5) hydrogen fluoride upon 60 g. of silicon dioxide ? 
 
 392. If 120 cc. of a mixture of CO and hydrogen are 
 exploded with oxygjen, 40 cc. of gas remain, of which 
 30 cc. are absorbed by KOH solution ; find the compo- 
 sition of the mixture. 
 
 393. If 20 1. of hydrogen diffuse through a porous 
 plate in 10 minutes, determine the volume of nitrogen 
 monoxide that will diffuse through in the same time. 
 
 394. If x cc. of a gas are measured at + 15 C. and 
 755 mm., the normal volume is 1:000 cc. ; find the 
 numerical value of x. 
 
 395. The sp. gr. of ammonia gas under standard con- 
 ditions is 0.591 ; what is its sp. gr. when the barometer 
 stands at 750 mm. ? 
 
 396. The sp. gr. of chlorine is 2.45 under standard 
 conditions ; what is the barometric height when the 
 sp. gr. is 2.40 ? 
 
 397. One 1. of hydrogen under standard conditions 
 weighs 0.0896 g. ; what is the weight of 1 1. when 
 the barometer stands at 740 mm. ? 
 
SYSTEMATIC REVIEW 201 
 
 398. One 1. of air under standard conditions weighs 
 1.29 g. ; what is the weight of 2.5 1. when the barome- 
 ter stands at 755 mm. ? 
 
 399. If 72 g. of an aqueous solution of H 2 O 2 , when 
 decomposed, give 2.79 1. of oxygen at C. and 760 
 mm., what is the percentage of H 2 O 2 in the solution? 
 
 400. Sea water contains 0.00475 g. CaCO 3 per 1. ; 
 what quantity of sea water would be needed to prepare 
 56 g. of lime ? 
 
 401. If 21 g. of borax are heated to constant weight, 
 what is the loss and what per cent, of the whole ? 
 
 402. Silicon fluoride was passed into cold water and 
 27 g. of SiO 2 were produced ; how much of the gas 
 was used ? 
 
 403. A gas is composed of 92.3 % of C and 7.7 % H ; 
 how many atoms of hydrogen are united to 2 atoms 
 of carbon ? 
 
 404. If hydrogen sulphide is diluted with 10 times 
 its volume of hydrogen, what volume of it, estimated as 
 pure gas, will be dissolved by 20 volumes of alcohol at 
 C. and 760 mm. ? 
 
 405. A Dumas bulb full of air weighs 13.3125 g. 
 After being filled with the vapor of carbon tetrachloride 
 at 100 C., it weighs 13.7969 g. Filled with water, it 
 weighs 141.3 g. The barometric reading is 755 mm. 
 What is the vapor density referred to air at C. and 
 760 mm. ? 
 
 406. What volume of air is required to oxidize one 
 formula-weight of zinc sulphide to ZnO and SO 2 , and 
 what volume of sulphur dioxide is produced ? Is the 
 
202 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 product more or less diluted with nitrogen than when 
 pure sulphur is burned, and by how much ? 
 
 407. How much chlorine is needed to displace bromine 
 in a solution of NaBr containing 16 g. ? 
 
 408. How many g. of sulphur in 3 1. of SO 2 ; 6 g. 
 of S0 8 ; 10 1. of H 2 S; 16 g. of K 2 SO 4 ? 
 
 409. If 8.132 1. of CO diffuse through an open- 
 ing in the time that .it takes 10.7 1. of marsh gas to 
 pass through, what is the density of marsh gas compared 
 with that of air ? 
 
 410. If 3.804 1. of oxygen diffuse through a certain 
 opening in the time that it takes 4.066 1. of CO to pass 
 through, what is the density of CO compared with that 
 of air ? 
 
 411. Determine the density of oxygen compared with 
 air, given that 5.706 1. of oxygen diffuse through a hole 
 in the time it takes 22.68 1. of hydrogen to pass through. 
 
 412. What volume of HI weighs the same as J 1. of 
 oxygen at C. and 760 mm. ? 
 
 413. A solution of common salt required 6 g. of 
 AgNO 3 to precipitate it completely as AgCl ; how much 
 sodium was present ? 
 
 414. If 150 tons of H 2 SO 4 are made from 110 tons of 
 a crude native sulphur, find the percentage of sulphur 
 in the native product. 
 
 415. One ton of iron pyrites containing 50 % sulphur 
 will make how much H 2 SO 4 ? 
 
 416. A fire extinguisher contains 2 Ib. of NaHCO 3 ; 
 how much H 2 SO 4 is needed to neutralize it ? 
 
SYSTEMATIC REVIEW 203 
 
 417. One g. of coal gave 0.2000 g. of barium sulphate; 
 1 g. of magnesium oxide and 0.50 g. of sodium carbonate 
 were used in the analysis. It was found upon a blank 
 analysis of the reagents that 10 g. of the magnesia and 
 5 g. of sodium carbonate together gave 0.1500 g. of 
 BaSO 4 . What is the percentage of sulphur in the coal ? 
 
 418. In the analysis of a limestone, 1 g. was taken 
 for analysis, and a precipitate of CaSO 4 weighing 0. 812 g. 
 was obtained. A precipitate of magnesium pyrophos- 
 phate weighing 0.385 g. was also obtained. What is 
 the percentage composition of the limestone in CaO 
 and MgO ? 
 
 419. Find the weight and volume of oxygen needed 
 for the complete combustion of 10 g. of C 2 H 4 . 
 
 420. How much CO 2 in a room 10 m. x 6 m. x 4 m., 
 if there is 1 volume CO 2 in 10,000 volumes of air? 
 
 421. How many 1. of CO 2 must be passed over hot 
 charcoal to give 100 g. of CO ? 
 
 422. Sixty 1. of steam require what volume of the 
 component gases ? 
 
 423. What volume of chlorine would be equal to 24 1. 
 of methane at C. and 760 mm. ? 
 
 424. If 200 cc. of oxygen are exploded with 40 cc- 
 of marsh gas, what are the volumes and percentage 
 compositions of the residual gases ? 
 
 425. If 3.36 g. of three different metals liberate 
 respectively 1344 cc., 3136 cc., and 1636 cc. of hydro- 
 gen, what metal was dissolved in each case ? 
 
 426. What weight of alcohol and what volume of 
 CO 2 on fermentation are produced by 21 g. of grape 
 sugar ? 
 
204 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 427. Gunpowder is composed of 75 parts niter, 15 
 parts charcoal and 10 parts sulphur. If all the carbon 
 forms CO 2 and the nitrogen is liberated, find the 
 volume of these gases evolved on the explosion of 1 g. 
 of gunpowder at standard conditions. 
 
 428. At the ordinary temperature and pressure, water 
 absorbs 50 % of its weight of ammonia. Calculate the 
 amount of sal-ammoniac and quicklime needed to pro- 
 duce 10 Kg. of hartshorn. 
 
 429. According to Boussingault, a m. 2 of leaf will 
 decompose in sunlight 1.108 1. of carbon dioxide 
 in an hour. Calculate in tons the amount of car- 
 bon assimilated in an hour by 1,000,000 trees, each 
 possessing 100,000 leaves and each leaf containing 
 25 cm. 2 Calculate the volume of the carbon so 
 assimilated, on the assumption that it possesses a sp. 
 gr. of 2.6. 
 
 430. If sea water contains 0.36 parts MgBr 2 in 1000, 
 how much of it would be needed to give 1 1. of bro- 
 mine (sp. gr. = 3.18)? 
 
 431. lodic acid may be obtained by passing a stream 
 of chlorine through water containing iodine in suspen- 
 sion ; how much iodine and chlorine will be needed to 
 prepare 100 g. of iodic acid ? 
 
 432. What weight of iron sulphide will be needed to 
 yield a 1. of hydrogen sulphide at C. and 760 mm., 
 and how much air will be required to burn this gas com- 
 pletely to water and sulphur dioxide ? 
 
 433. Manchester coal gas contains 35 % by volume of 
 marsh gas ; calculate the weight of this gas in a gas- 
 ometer holding 100,000 ft. 3 of coal gas. 
 
SYSTEMATIC REVIEW 205 
 
 434. If 100 g. of pure silver cyanide are shaken up 
 with 120 g. of hydrochloric acid containing 26.1% of 
 HC1, how much silver chloride is produced and what is 
 the percentage amount of hydrocyanic acid in solution? 
 
 435. A water solution of potassium iodide having 
 20 g. in it is treated with chlorine ; what volume of 
 chlorine will be needed to replace all the iodine ? 
 
 436. Sulphuric ether vapor is exploded with 60 times 
 its volume of air ; find volumes of residual gases. 
 
 437. If 300 cc. of oxygen were added to 200 cc. of a 
 mixture of H, CO and CH 4 , and if, after exploding, the 
 volume was 220 cc., and after washing with KOH so- 
 lution 80 cc., what was the composition of the mixture? 
 
 438. Five volumes of a hydrocarbon, C n H 2ra , are sub- 
 mitted to combustion ; how many volumes of oxygen 
 are required for its complete combustion and how many 
 volumes of CO 2 are generated ? 
 
 43d. Find weight of hydrogen necessary to unite 
 with oxygen in 200 g. of air to form water. 
 
 440. Find volume of oxygen needed to unite with 
 2 1. of hydrogen to form water. What volume with 
 (a) 60 cc. ; (5) 60 dm. 3 ; (c) 60 1. ; (d) 60 qt. ; 
 0) 60 M. 3 ; (/) 700 volumes? 
 
 441. Find the weight of (a) 700 cc. of dry hydrogen 
 at C. and 760 mm. ; (5) of 2000 cc. ; (c) of 13 1.; 
 (d) 16J dm. 3 ; (e) 3 m. 3 
 
 442. One Kg. of water contains hydrogen and oxygen 
 in what proportion by weight and by volume ? 
 
 443. Find the weight of 1200 1. of phosphorus vapor. 
 
 444. Arsenic is burned in oxygen and 103 g. of the 
 oxide are produced ; how much arsenic was used ? 
 
206 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 445. A tank holds 20 g. of oxygen ; what weight (a) 
 of N 2 O and of (6) NO will it hold ? 
 
 446. If potassium is heated in contact with 10 g. of 
 N 2 O and NO separately, what volume of nitrogen will 
 be left in each case? 
 
 447. How much pure HNO 3 in 200 tons of HNO 3 , 
 200 g. of which will neutralize 88.6 g. of pure NaOH ? 
 
 448. What loss in weight should 100 Ib. of gypsum 
 undergo when heated to + 250 C.? 
 
 449. If 0.4 g. of iron dissolved in acid gave 167.4 cc. 
 of hydrogen at -f 12 C. and 750 mm., what is the purity 
 of the iron? 
 
 450. How much coke (90 % pure carbon) would be 
 needed to make 100 m. 3 of CO, measured at + 30 C. 
 and 850 mm.? 
 
 451. If 0.2 g. of a metal yield 77.39 cc. of hydrogen, 
 how much will yield 309 cc.? 
 
 452. If 600 cc. oxygen at + 12 C. and 720 mm. are 
 required, and the materials on hand are bleaching pow- 
 der, cobalt oxide and water, how much bleaching pow- 
 der will be used? 
 
 453. What volume of HI contains 2 g. of iodine at 
 standard conditions? 
 
 454. If 1 cc. HC1 neutralizes 0.0106 g. Na 2 CO 3 , what 
 weight of AgCl will be thrown down when 1 cc. is 
 added to excess of AgNO 3 solution? 
 
 455. A mixed gas consists of hydrogen 46%, CH 4 
 40%, and olefiant gas 14% by volume ; how much air 
 would be needed to burn 100 1. of this gas? 
 
 456. Find the weight of 20 1. of air containing 21 % 
 of oxygen and 79 % of nitrogen at C. and 760 mm. 
 
SYSTEMATIC REVIEW 207 
 
 457. In 300 g. of common alum, find how much alu- 
 minum is present. 
 
 458. A slab of marble weighs 200 Kg. (a) How 
 much lime will it make ? (6) What volume of water 
 will just slake this lime? (c) How many 1. of air will 
 transform it into the carbonate ? (1 volume of CO 2 in 
 10,000 volumes of air.) 
 
 459. When 50 g. of ZnO were made, how much zinc 
 was needed and what volume of oxygen was used? 
 
 460. What weight of HC1 would be needed to dis- 
 solve 200 g. of ZnO? 
 
 461. If 20 cc. of H 2 SO 4 solution yield 2.468 g. of 
 BaSO 4 when precipitated with BaCl 2 , what weight of 
 this acid will be required to neutralize 10 g. of Na 2 CO 3 ? 
 
 462. What volume of sulphuric ether vapor corre- 
 sponds in weight to (a) 11. of nitrogen ; (J) 1 1. of 
 air; (V) 1 1. CO 2 ; (d) 1 1. of chlorine? 
 
 463. What weight of phosphoric acid could be made 
 from 10 Ib. of phosphorus? 
 
 464. On heating sodium phosphate till there is no 
 longer a loss in weight, one gets 100 g. of residue ; 
 what was the original weight? 
 
 465. An unknown volume of hydrogen sulphide re- 
 quired 110.34 cc. of chlorine for complete decomposi- 
 tion ; what was the volume of the hydrogen sulphide ? 
 
 466. One g. of NaCl in solution was mixed with an- 
 other solution containing 2 g. of AgNO 3 . Find weight 
 of residue. Which one was in excess and how much ? 
 
 467. How much CaC 2 will produce enough gas from 
 water to yield on combustion 20 1. of CO 2 , measured at 
 + 10 C. and 730 mm. ? 
 
208 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 468. If 25 g. of sodium acetate yield a certain weight 
 of CH 4 , what volume of air (21 % oxygen) is needed 
 to burn this gas? 
 
 469. If 24 g. of magnesium are heated in a current 
 of nitrogen, what is the weight of the product? 
 
 470. I need 2 1. of CO 2 . What weights of (a) 
 Na 2 CO 3 and (5) NaHCO 3 would have to be treated 
 with acid to give this volume? 
 
 471. What is the weight of 100 1. of SO a , measured 
 at + 31 C. and 721 mm. ? 
 
 472. What volume of CO, at + 800 C. and 700 mm., 
 would be required to reduce 1 Kg. of ferrous oxide to 
 metallic iron ? 
 
 473. A 1. of mineral water yielded 0.0134 g. of Agl ; 
 how much iodine is contained in 1,000,000 cc. of the 
 water ? 
 
 474. From the vapor densities of these gases com- 
 pute their molecular weights : (a) oxygen, 16 ; (5) car- 
 bon dioxide, 22 ; (<?) nitrogen, 14; (<f) nitric oxide, 15; 
 (e) carbon monoxide, 14 ; (/) marsh gas, 8. 
 
 475. Find the vapor densities of these molecules, 
 computing the molecular weights by affixing the atomic 
 weights:' (a) HC1; (5) C 2 H 2 ; (c?) NH 3 ; (d) PH 3 ; 
 0) 2 ; (/) P 4 ; (g) Hg ; (A) CO ; (*) CH 4 . 
 
 476. (a) The vapor density of alcohol is 23. As- 
 certain which of the following is the proper formula 
 for alcohol: (1) C 4 H 12 O 2 ; (2) C 2 H 6 O ; (3) C 8 H 24 O 4 . 
 (7>) The vapor density of acetic acid is 29.7, and the 
 percentage composition indicates one of these symbols. 
 Which is correct: (1) H 2 CO ; (2) H 6 C 3 O 3 ; (3) 
 H 4 C 2 O 2 ? (V) To which of these formulas does the 
 density 33.5 apply: (1) C1O 2 ; (2) C1 2 O 4 ? 
 
SYSTEMATIC REVIEW 209 
 
 477. What weight of calcium carbonate is required 
 to neutralize 400 cc. of hydrochloric acid solution which 
 contains 100 g. of the pure substance ? 
 
 478. The specific heat of phosphorus is 0.189. The 
 vapor density of phosphorus is 62. How many atoms 
 are there in the molecule of phosphorus gas ? 
 
 479. How much nitrogen may be obtained from 22 g. 
 of ammonium nitrite ? What volume would it occupy 
 at + 20 C. and 756 mm. pressure? 
 
 480. In every 100 parts of nitric acid there are 1.58 
 parts of H, 76.19 parts of O, and 22.23 parts of N. 
 Does this fix the formula of the acid? Why do we 
 accept the formula HNO 3 ? 
 
 481. If 100 g. of gypsum are heated, what volume 
 of steam at + 300 C. is given off? 
 
 482. How much carbon dioxide by weight and by 
 volume can be obtained from 53 g. of sodium carbonate? 
 What volume would the gas occupy at + 20 C. and 
 under a pressure of 75 mm. ? 
 
 483. A 1. of a certain gas weighs 7.50 g., while a 
 1. of hydrogen under the same conditions weighs 0.050 g. 
 The atomic weight of the element composing the gas 
 is 75. How many atoms are there in one molecule of 
 the gas? 
 
 484. What volume of oxygen under standard condi- 
 tions can be obtained from 5 g. of potassium chlorate? 
 
 485. What is the atomic weight of silver, if the 
 specific heat is 0.056 and the atomic heat is 5.99 ? 
 
 486. Find the specific heat of silver, if the atomic 
 weight is 107 and the atomic heat is 5.99. 
 
210 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 487. Compute atomic heats from the data that 
 follow: (a) Hg, at. wt. 199, sp. ht. 0.033; (ft) iodine, 
 at. wt. 126, sp. ht. 0.054; (<?) U, at. wt. 238, sp. ht. 
 0.028 ; (d) Br, at, wt. 80, sp. ht. 0.1071. 
 
 488. Take 6.4 as the atomic heat of the following 
 and the specific heats as given, and find the approxi- 
 mate atomic weights: (a) Al, 0.22; (ft) Fe, 0.11; 
 (<?) Zn, 0.094 ; (d) K, 0.17 ; (e) Pb, 0.031. 
 
 489. Hydrogen is passed over hot copper oxide, and 
 the water that is formed is absorbed by calcium chloride 
 and its weight ascertained to be 3 g. ; what has been 
 the loss of weight of the tube containing the copper 
 oxide ? 
 
 490. Two 1. of a gas which is half oxygen and half 
 sulphur weigh 5.76 g. ; what is its formula ? 
 
 491. A compound of nitrogen and hydrogen, of which 
 the nitrogen is \$, weighs 0.765 g. to the 1.; what gas 
 is it? 
 
 492. Two 1. of a compound of oxygen and nitrogen 
 weigh 3.96 g. The nitrogen is ^ of the whole. 
 What is the compound ? 
 
 493. Find the specific heat of each of the following 
 elements from the constant atomic heat 6.4 : (a) Mg, 
 at. wt. 24 ; (ft) Ni, at. wt. 58 ; (c) Pt, at. wt. 193 ; 
 (cf) Na, at. wt. 23. 
 
 494. The atomic weight of copper is either 31.5 or 
 63; find which is correct if the specific heat is 0.094. 
 
 495. If zinc has an atomic weight of either 32.5 or 
 65 or 130, find which is correct if the specific heat of 
 Zn is 0.094. 
 
SYSTEMATIC REVIEW 211 
 
 496. If 1 1. of acetylene is burned, what volume 
 of oxygen is necessary for the combustion and what 
 volume of carbon dioxide will be formed? 
 
 497. What weight of carbon dioxide would be 
 obtained by burning 17 g. of carbon ? 
 
 498. What volume of oxygen will unite with 730 cc. 
 of carbon monoxide to form carbon dioxide and what 
 will be the volume of the carbon dioxide produced? 
 
 499. Supposing standard conditions in each case, 
 find the weight of a 1. of ammonia, NH 3 ; CO 2 ; CO; 
 N 2 ; H 2 S; N 2 O 3 ; C1 2 . 
 
 500. By analysis we find aluminum-methyl to con- 
 tain 37.5 % of Al, 50 % of C, and 12.48 % of H. The 
 vapor density is very nearly 72 at + 160 C., but at 
 + 220 C. it is found to be nearly 36. Can you ac- 
 count for the vapor density varying at the two tem- 
 peratures ? What is the formula of the compound? 
 
 501. Carbon and oxygen form what compounds? If 
 1 1. of oxygen combines with carbon to form each of 
 these compounds, what will be its volume in each case, 
 at the standard temperature and pressure? 
 
 502. What is the sp. gr. referred to air and to hydro- 
 gen of a gas that requires 12 minutes to escape through 
 an opening, while the same volume of air under same 
 conditions of temperature and pressure requires 20 
 minutes ? 
 
 503. If an ore contains 10% of moisture and 12% of 
 copper, what will be the percentage of copper in the ore 
 dried at +105 C.? 
 
 504. If an ore contains 15 % of moisture and 50% of 
 manganese, what will be the percentage of manganese 
 in the dry ore ? 
 
212 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 505. What is the sp. gr. referred to air of a gas that 
 escapes in 14.5 minutes through an opening, through 
 which, at the same temperature and pressure, the same 
 volume of air requires 19.5 minutes ? 
 
 506. What is the vapor density of a gas that escapes 
 in 7 minutes and 30 seconds from an opening, while the 
 same volume of air under the same conditions requires 
 5 minutes and 10 seconds ? 
 
 507. If a sample of coal contains 10% of ash on the 
 dry basis, what is the percentage of ash in the natural 
 coal containing 5 % of moisture ? 
 
 508. A sample of ore contained 20 % of lead, 14 % of 
 zinc and 14% of water; what are the percentages of 
 lead and zinc on the dry basis ? 
 
 509. A clay was partially dried and then contained 
 SiO 2 , 50 %, and water 1 % ; the original clay contained 
 12 % of water ; what is the percentage of the silica in 
 the original sample ? 
 
 510. Find the proportion by weight and by volume 
 in which ethane gas will combine with oxygen. 
 
 511. A quantity of hydrogen measures 76 1. at 
 + 100 C. and 746 mm. pressure; calculate its weight. 
 
 512. The equivalent of mercury is 100, and the for- 
 mula of mercuric chloride is HgCl 2 ; find its specific 
 heat. 
 
 513. The formula of ethane is C 2 H 6 . Calculate the 
 density of its vapor (a) compared with hydrogen; (6) 
 compared with air. 
 
 514. If an ore contains 60% of iron in the dry sample, 
 what is the percentage of iron in the natural ore which 
 contains 10 % of water ? 
 
SYSTEMATIC REVIEW 213 
 
 515. What is the amount of " available oxygen " in 
 a cc. of a solution of potassium permanganate contain- 
 ing 50 g. per 1. ? 
 
 516. Find the weight of 10 cc. of iron when sp. gr. 
 
 is 7.85. 
 
 517. If 100 g. of a solution of hydrogen dioxide in 
 water gave off, when heated, 5 1. of oxygen, what is 
 the percentage of H 2 O 2 in the solution ? 
 
 518. What weight of potassium permanganate, in 
 acid solution, will be reduced by 5000 cc. of hydrogen 
 sulphide at standard conditions ? 
 
 519. Calculate the density (referred to air) of C 2 H 4 . 
 
 520. (#) The vapor density of chlorine is 35, the 
 atomic weight is 35 ; find the number of atoms per 
 molecule. (6) The vapor density of Zn is 32.5, its 
 atomic weight is 65 ; how many atoms in its molecule ? 
 (<?) Phosphorus has atomic weight 31, vapor density 62. 
 compute as before. (d) The atomic weight of ozone 
 is 16, its vapor density is 24 ; compute. 
 
 521. The atomic weight of copper is 63.3 and the 
 formula of copper chloride is CuCl 2 . The atomic weight 
 of silver is 108. Determine the specific heat of silver 
 and copper respectively. 
 
 522. What weight of ammonium chloride would be 
 required in order to prepare 5 Kl. of ammonia ? 
 
 523. How many cc. of nitrogen and of hydrogen 
 would be produced by decomposing 20 cc. of ammonia 
 by means of electric sparks ? 
 
 524. What volume and weight of air would contain 
 enough oxygen to burn exactly 25 1. of hydrogen ? 
 
214 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 525. What volume of chlorine would be required to 
 convert 20 1. of sulphur dioxide dissolved in water into 
 sulphuric acid, and what weight of sulphuric acid would 
 be produced ? 
 
 526. An iron rod 250 cm. long at -f 10 C. is 0.09 
 cm. longer at -f 40 C. ; what will its length be at 
 + 60 C C.? 
 
 527. What volume of chlorine at N.T.P. would be 
 required to convert an acidified solution of 5 g. of crys- 
 tallized ferrous sulphate into a ferric salt? 
 
 528. How many cc. of a solution of potassium dichro- 
 mate, containing 50 g. of the salt per 1., would be re- 
 quired to oxidize 5 g. of ferrous chloride to a ferric salt ? 
 
 529. What are the laws of diffusion of gases ? If 20 
 volumes of hydrogen take 10 minutes to diffuse out of 
 a vessel, how long will 50 volumes of oxygen take to 
 diffuse out under like conditions ? 
 
 530. If 0.428 g. of one of the oxides of manganese, 
 when heated with hydrochloric acid, gave 42 cc. of 
 chlorine, at N.T.P., which oxide of manganese was 
 used ? 
 
 531. Ferric oxide contains 30% of oxygen and its 
 molecule 3 atoms of oxygen ; what is its molecular 
 weight ? 
 
 532. If 1337 g. of copper sulphate yield 317 g. of 
 copper and its molecular weight is 267.4, how many 
 atoms of copper are there in a molecule of the sulphate ? 
 
 533. A sample of silver nitrate weighing 2.40 g. was 
 brought into solution and treated with a soluble chloride 
 (excess). The weight of silver chloride precipitated 
 was 2. 01 g. What was the purity of the sample ? 
 
SYSTEMATIC REVIEW 215 
 
 534. What weight of zinc (98 %) will be required for 
 the liberation of the hydrogen from 10 g. of hydro- 
 chloric acid containing 39.1 % of HC1? 
 
 535. What weight of sulphuric acid containing 
 27.32 % H 2 SO 4 will be required for interaction with 
 2.17 g. of iron wire (99% pure)? 
 
 536. On the top of a mountain the barometer stands 
 at 70 cm. and the temperature is +10 C., while in the 
 valley the barometer stands at 758 mm. and the ther- 
 mometer at + 20 C. ; what are the relative densities of 
 the air in the two places ? 
 
 537. If 0.2815 g. of calcite was dissolved in 30 cc. of 
 normal HNO 3 , and the excess of acid determined by 
 normal NaOH, of which 24.43 cc. were required, what 
 percentage of CO 2 did the sample contain? 
 
 538. If 2.0876 g. of hydrogen, when passed over 
 heated oxide of copper, yielded 18.7406 g. of water, what 
 is the equivalent of oxygen ? 
 
 539. What is the absolute density of hydrogen at 
 + 20 C. and 740 mm. pressure? 
 
 540. What is the absolute density of air at +10 C. 
 and 750 mm. pressure? The absolute density at the 
 standard conditions is 1.293. 
 
 541. If 400 cc. of gas, with the density 16, and 
 measured at +25 C. and 750 mm. pressure, are to 
 be brought to a temperature of + 10 C. and a pressure 
 of 760 mm., what weight of this final gas can be con- 
 tained in a vessel of 100 cc. capacity? 
 
 542. If 10 g. of a gas, measured at -48 C. and 600 
 mm. pressure, were expanded by heating to + 177 C. 
 and reducing the pressure to 480 mm., and the rarefied 
 
216 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 gas, 250 cc., weighed 0.5 g., what was the original volume 
 of gas and what was the density of the gas at its original 
 and final volume ? 
 
 543. If 10 1. of a gas, measured at + 20 C. and 750 
 mm. pressure, weighed 14 g., what weight of this gas 
 could be contained in a smaller vessel holding 4 1. at 
 + 10 C. and 760 mm. pressure? 
 
 544. What volume will 1000 cc. of a gas at -f 300 C. 
 and 740 mm. pressure occupy when reduced to standard 
 conditions ? 
 
 545. A piece of metal weighing 30 g. displaced 20 cc. 
 of water; what is the relative density of this metal 
 referred to water? 
 
 546. A vessel weighing 6.448 g. weighed 7.963 g. 
 when filled with water and 8.266 g. when filled with a 
 salt solution ; what is the relative density of this solu- 
 tion referred to water? 
 
 547. What is the relative density of hydrogen sul- 
 phide referred to air and also to oxygen ? 
 
 548. What is the relative density of hydrogen chloride 
 referred to hydrogen, air, oxygen and chlorine? 
 
 549. If 8 g. of oxygen were mixed with 10.08 g. of 
 hydrogen, and both gases were measured at the stand- 
 ard conditions, what was the relative density of this 
 mixture? 
 
 550. A volume of gas, with the relative density 
 0.8757, was found to measure 1560 cc. when transferred 
 to a vessel over water at + 18 C. and 742.4 mm.; what, 
 is the weight of the dry gas here concerned? 
 
 551. What volume of chlorine, measured at + 10 C. 
 and 770 mm. pressure, would be required to convert 
 5 g. of phosphorus trichloride into the pentachloride ? 
 
SYSTEMATIC REVIEW 217 
 
 552. What weight of pure sulphuric acid should be 
 obtained from 100 tons of "pyrites" containing 35 % of 
 sulphur ? 
 
 553. The coefficient of linear expansion of iron is 
 0.000011 ; how much must an iron rod 40 ft. long be 
 heated to expand 1 in. ? 
 
 554. If 240 cc. of gas at a pressure of 740 mm. were 
 admitted into an empty vessel of 800 cc. capacity, what 
 was the pressure of the gas at this new volume ? 
 
 555. If 500 cc. of oxygen, absolute density 1.429, 
 were compressed to a volume of 125 cc. at constant 
 temperature, what was the density of the gas at this 
 final volume ? What would be the weight of 50 cc. of 
 the compressed gas ? 
 
 556. A volume of gas measured 1 ft. 3 at 4 F. and 
 30 in. pressure ; what will be its volume at -f- 68 F. 
 and 39.4 in. pressure? 
 
 557. What volume of liquid carbon dioxide, measured 
 at C., will be required to give 75 1. of the gas at C. 
 and 760 mm. pressure? 
 
 558. If 0.352 g. of a sample of pyrolusite was heated 
 with hydrochloric acid, and the chlorine which was 
 evolved was passed into a solution of potassium iodide, 
 where it liberated 0.864 g. of iodine, what was the per- 
 centage of pure MnO 2 in the sample ? 
 
 559. If 0.5 g. of pyrolusite containing 92% of pure 
 MnO 2 was heated with strong hydrochloric acid, and 
 the resulting chlorine led into a solution of potassium 
 iodide, what amount of iodine would be liberated ? 
 
 560. If 35 cc. of a solution of potassium perman- 
 ganate containing 15 g. per 1. were required to oxidize 
 
218 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 50 cc. of acidified solution of ferrous sulphate to ferric 
 sulphate, what was the amount of metallic iron in a 1. 
 of the ferrous sulphate solution ? 
 
 561. What volume of chlorine, at + 17 C. and 750 
 mm. pressure, would be required to convert 6 g. of tin 
 into stannic chloride ? 
 
 562. A volume of gas weighing 5 g. was expanded at 
 a constant temperature till the pressure was reduced 
 to | of its former value, and 500 cc. of the rarefied 
 gas weighed 1.25 g. What was the original volume 
 of the gas ? Calculate also the original density, 
 assuming the original observations made at standard 
 conditions. 
 
 563. A volume of gas measuring 600 cc. at 760 mm. 
 pressure was expanded to a volume of 1000 cc. at con- 
 stant temperature ; what was the final pressure of the 
 gas? 
 
 564. A solution contains 48 g. of Pb (NO 3 ) 2 per 1.; 
 how much H 2 SO 4 will 10 cc. of this solution 
 precipitate ? 
 
 565. Calculate the volume of chlorine liberated in the 
 action of 40 g. of potassium dichromate upon a hydro- 
 chloric acid solution. 
 
 566. If 0.535 g. of a sample of pyrolusite, when acted 
 on with a mixture of sulphuric acid and oxalic acid, 
 produce 0.48 g. of carbon dioxide, what was the per- 
 centage of pure MnO 2 in the sample ? 
 
 567. The absolute density of oxygen is 1.429. When 
 a given volume of this gas is warmed from 0C. to 
 + 40 C. under a constant pressure, what will the abso- 
 lute density of the gas become ? 
 
SYSTEMATIC REVIEW 219 
 
 568. A volume of gas with the absolute density 4 and 
 measuring 250 cc. at C. was expanded by warming, 
 under constant pressure, to a volume of 600 cc. What 
 increase in temperature was required, and what would 
 be the weight of 300 cc. of the rarefied gas ? 
 
 569. If 500 cc. of a gas, the absolute density of 
 which is 6, must be reduced to a density of 0. 75 at con- 
 stant temperature, what will be the volume of this rare- 
 fied gas ? Calculate also the weight of 400 cc. of the 
 rarefied gas. 
 
 570. Calculate the relative density of hydrogen 
 chloride, 5 1. of which under standard conditions weigh 
 8.205 g. 
 
 571. Calculate the relative density of chlorine, 100 
 cc. of which at standard conditions weigh 0.322 g. 
 
 572. The sp. gr. of chlorine is 2.449; what is its rel- 
 ative density upon the oxygen standard? 
 
 573. What is the weight of BaO in 1.9327 g. of 
 BaCr0 4 ? 
 
 574. What is the weight of CaO in 2.9478 g. of 
 CaS0 4 ? 
 
 575. What weight of MnCO 3 yields on ignition 
 1.450 g. of Mn 3 O 4 ? 
 
 576. How much arsenic is there in 5 g. of As 2 S 3 ; 
 of As 2 S 5 ; of Mg 2 As 2 O T ? 
 
 577. How much Agl can be made from a Ib. of pure 
 silver ; how much AgBr ; how much AgCl ? 
 
 578. If 1.10 g. of stibnite gave on analysis 0.5987 g. 
 of Sb 2 O 4 , what was the percentage of antimony ? 
 
 579. Air liquefies at 182 C. Express this temper- 
 ature on the Fahrenheit scale. 
 
220 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 580. When water in an open dish boils at -f 209 F., 
 what would be the reading of an accurate barometer 
 placed near by ? 
 
 581. Reduce 12 1. of oxygen, measured at +47 C. 
 and under a pressure of 782 mm. of mercury, to the 
 standard conditions. 
 
 582. What will be the volume of 9 1. of hydrogen 
 when heated to + 120 C. and under a pressure of 423 
 mm.? 
 
 583. Given 27 cc. of nitrogen at + 14 C. and 752.1 
 mm., what will be its volume at -f 20 C. and 767.8 
 mm.? 
 
 584. What is the weight of 77.2 cc. of air, measured 
 over water at + 27 C. and 758 mm. pressure ? 
 
 585. What is the weight of 17 1. of Irydrogen, meas- 
 ured at + 12 C. and 3 atmospheres pressure ? 
 
 586. What is the weight of 85 cc. of NH 3 , measured 
 over mercury at + 140 C. and under a pressure of 770 
 mm.? Given the tension of mercury vapor at + 140 C. 
 = 1.76 mm. 
 
 587. Find the density referred to air of chloroform 
 vapor, given the following data for Dumas' method : 
 weight of bulb and air at + 20.5 C. and 763.9 mm. = 
 34.8451 g. ; weight of bulb and vapor at + 116.5 C. and 
 763.9 mm. = 35.8430 g.; volume of air in bulb at 
 + 20.5 C. = 394.93 cc. 
 
 588. An object, the sp. gr. of which is 3.38, weighed 
 39.7250 g. in air when weighed with brass weights; 
 what is its true weight ? 
 
 589. An object, the sp. gr. of which is 0.95, weighed 
 17.8540 g. in air when weighed with brass weights; 
 what is its true weight ? 
 
SYSTEMATIC REVIEW 221 
 
 590. A bar of gold, sp. gr. = 19.3, weighed 10.73685 
 Kg. when weighed in air with brass weights; what 
 is the true weight ? 
 
 591. A piece of pyrrhotite, sp. gr. = 4.58, weighed in 
 air 47.3854 g. when weighed with platinum weights ; 
 what is its true weight ? 
 
 592. A piece of antimony, sp. gr. =6.71, weighed 
 75 g. in air, the weights used being 50 g. brass, 20 g. 
 and 5 g. platinum ; what is the true weight ? 
 
 593. If 50 cc. of CH 4 , 50 cc. of H 2 , and 50 cc. of 
 C 2 H 2 were mixed with 450 cc. of oxygen and exploded, 
 what would be the resulting volume at the same tem- 
 perature and pressure,? (Assume that the temperature is 
 below + 100 C.) 
 
 594. How many amperes are flowing in a circuit 
 which, in the course of 1 hr. and 15 min., has deposited 
 30.186 g. of silver? 
 
 595. How many g. of lead shot at + 200 F. must be 
 used to raise the temperature of 400 g. of water from 
 + 40F. to +90F.? 
 
 596. How much alcohol at 10 C. must be mixed 
 with 200 g. of chloroform at + 30 C., that the final 
 temperature may be + 10 C.? 
 
 597. If a 50 g. lump of silver, left in ice water until 
 it is cooled to C., is dropped into 100 g. of ether 
 at -h 30 C., what will be the temperature of the mixture ? 
 
 598. We have at our command a waste acid from the 
 nitrating of glycerine, the composition of which is : 
 sulphuric acid, 62.18%; nitric acid, 19.07%; and 
 water, 18.75%. We also have an oil of vitriol contain- 
 ing 97 % by weight of H 2 SO 4 , and a commercial nitric 
 
222 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 acid containing 87% by weight of HNO 3 . What 
 weights of each must be taken to give 1000 Ib. of a 
 mixture containing 60% of H 2 SO 4 , 28% of HNO 3 , 
 and 17 % of water, without adding water ? 
 
 599. Bearing in mind that the molecule of mercury 
 vapor is monatomic, calculate the weight of 500 cc. of 
 that gas. 
 
 600. If we have two alloys, viz., a brass containing 
 65 % of copper and 35 % of zinc, and a German silver 
 containing 56 % of copper, 24 % of zinc, and 20 % of 
 nickel, supposing that there is no loss by oxidation or 
 volatilization during the fusion, what will be the com- 
 position of the alloy formed by melting these two alloys 
 together in such proportion that it contains 30 % of zinc ? 
 
 601. Suppose that we desire to prepare 100 Ib. of an 
 alloy containing 70 % of copper, 20 % of zinc, and 10 % 
 of tin ; we have at our command, pure copper, a brass 
 containing | copper and J zinc, and a solder containing 
 J zinc and J tin : how much of each must be taken ? 
 
 602. Given pure silver and an alloy containing 890 
 parts of silver and 110 parts of copper, how many oz. 
 of each must be taken to form 1000 oz. of an alloy 
 containing 925 parts of silver and 75 parts of copper ? 
 
 603. Given a mixture of silver chloride and silver 
 bromide, the weight of which is 1.5 g., analysis showing 
 the mixture to contain 1 g. of metallic silver, what are 
 the weights of the chlorine and of the bromine in the 
 mixture ? 
 
 604. The analysis of a dolomite gave 2 % of silica, 
 and the remainder was calcium and magnesium carbon- 
 ates. The determination of magnesia gave 10 % of 
 MgO. What was the percentage of carbon dioxide ? 
 
SYSTEMATIC REVIEW 223 
 
 605. How many ft. 3 of air at + 70 C. are needed for 
 the combustion of 1 Ib. of a coal having the analysis : 
 carbon, 90%; hydrogen, 5%; oxygen, 3.5%; nitro- 
 gen, 0.1%; sulphur, 0.5%. Assume the factor for 
 excess as 2. 
 
 606. Calculate the number of ft. 3 of air at + 60 F. 
 needed for the combustion of 1 ton of a coal having 
 the composition: carbon, 74.60 %; hydrogen, 4.89%; 
 oxygen, 6.90%. Assume the factor for excess as 1.5. 
 
 607. How many calories are required to raise 500 g. 
 of a substance of specific heat 0.5 from +15 C. to 
 
 + 37C.? 
 
 608. How many g. of hot water at 4- 100 C. must be 
 poured into 3 1. of cold water at + 4 C. to warm it to 
 + 20 C. ? 
 
 609. When 200 g. of hot water at + 80 C. are poured 
 into a pail of water at + 14 C., the temperature of the 
 mixture becomes + 20 C. How many g. of cold water 
 must there have been in the pail at first ? 
 
 610. If 80 g. of water at + 100 C. are poured into 
 80 g. of water at + 10 C., what will be the tempera- 
 ture of the mixture ? 
 
 611. If 500 g. of water at 4- 90 C. are poured into 
 600 g. of water at + 30 C., what will be the resulting 
 temperature ? 
 
 612. One Kg. of copper at 4- 100 C., when plunged 
 into 600 g. of water at + 10 C., raises the temperature 
 of the water to + 22 C. Find the specific heat of 
 copper. 
 
 613. Find the water equivalent, or thermal capacity, 
 of a brass calorimeter weighing 92 g. 
 
224 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 614. How many g. of mercury at -f- 98 C. must be 
 poured into 100 g. of water to raise its temperature 
 from + 5 C. to + 18 C. ? 
 
 615. How many calories of heat are required to raise 
 the temperature of (a) 5 g. of water + 10 C. ; (5) 8 g. 
 of zinc +20 C.? 
 
 616. How many calories of heat are given out (a) 
 when 2 Kg. of water cools + 90 C. ; (>) when 700 g. 
 of copper cools from -f 250 C. to + 140 C.? 
 
 617. If 500 g. of water at + 5C. and 500 g. of mer- 
 cury at C. are each given the same quantity of heat, 
 how hot will the mercury become when the water has 
 been heated to + 10C.? 
 
CHAPTER XIV 
 
 A Progressive Series of Problems based on Equa- 
 tions taken from a recent text-book on 
 General Inorganic Chemistry 
 
 1. If 63 g. of sodium react with hydrogen monox- 
 ide, what is the weight of gas evolved? 
 
 2. If 32 g. of muriatic acid are treated with zinc, 
 how many g. of salt are produced ? 
 
 3. Zinc is boiled with caustic soda solution and 10 1. 
 of a gas are given off. Find weight of zinc and caustic 
 soda used. 
 
 4. A solution containing 27 g. NaOH is heated with 
 an excess of zinc. Find weight and volume of gas 
 produced. 
 
 5. What weight of oxygen and what other compo- 
 nent is required to make 100 g. of BaO 2 ? 
 
 6. Sodium peroxide, when added to water, liberates 
 10 1. of oxygen at + 6 C. and 662 mm. Find weight 
 of NaOH produced. 
 
 7. What volume of ozone can be made from 300 g. 
 of oxygen ? 
 
 8. What weight of water is required to decompose 
 completely 23 g. of Na 2 O 2 ? 
 
 9. What weight of NaOH can be made from 200 g. 
 of sodium monoxide ? 
 
 225 
 
226 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 10. On heating 392 g. of copper hydroxide, what 
 weights of products do you get ? 
 
 11. Into how many g. of the resultant gases do 222 1. 
 of HC1 decompose ? 
 
 12. In the synthesis of 100 g. of table salt, what 
 weights of the components are used and what volume of 
 the gaseous constituent is needed at | atmospheric 
 pressure and a temperature of + 10 C. ? 
 
 13. What volume of HC1 is needed to produce 30 g. 
 of MnCl 2 ? 
 
 14. What weight and volume of oxygen will be 
 needed to liberate 102 m. 3 of chlorine from muriatic 
 acid? 
 
 15. We need 2 tons of bromine. What weight of 
 chlorine is required and how much NaCl will be pro- 
 duced? 
 
 16. If 110 g. of Nal are decomposed by chlorine, 
 what are the weights of the products, and what is the 
 volume of chlorine at + 300 C. and 663 mm.? 
 
 17. If 222 1. of chlorine are dissolved in water and 
 exposed to the sun, what weights of materials will be 
 left after complete decomposition? 
 
 18. How much KOH would be needed to make 79 g. 
 of KC1? 
 
 19. Fluorine and water gave 63 1. of HF at C. 
 and 771 mm. Find volume of fluorine used at 10 C. 
 and 621 mm. 
 
 20. NaCl + H 2 SO 4 will give either sodium sulphate 
 or sodium hydrogen sulphate according to the tempera- 
 ture. If 100 g. of H 2 SO 4 are used in either case, what 
 weight of salt will be required? 
 
PROBLEMS BASED ON EQUATIONS 227 
 
 21. NaBr will give what volume and weight of HBr 
 when treated with 16 g. of H 3 PO 4 ? 
 
 22. PBr 3 with 100 g. of H 2 O will give what weights 
 and what volume of gaseous product? 
 
 23. Of phosphorus 10 lb., of bromine 6 lb., and of 
 water 1 lb. are mixed. After complete reaction, what 
 weights of products and of excess do you get? 
 
 24. If 20 g. of HKF 2 decompose, what weights of 
 w r hat substances result? 
 
 25. What weight of fluorspar will give 10 lb. of CaSO 4 
 when treated with oil of vitriol? What volume of gas 
 will result at 40 C. and 2 atmospheres pressure? 
 
 26. An iron ore is 60 % silica. What weight of sam- 
 ple was taken if it requires 20 1. of HF to decompose it? 
 
 27. The decomposition of 2 lb. LiCl will give how 
 many 1. of chlorine at 1 C. and 600 mm. ? 
 
 28. To make 1 Kg. of potassium, what weight of car- 
 bon and K 2 CO 3 will be needed, and what volume of gas 
 will be evolved? 
 
 29. What weight of ammonium salt is required by 
 13 1. of nitrogen at +112 C. and 300 mm. ? 
 
 30. What weight of NH 4 NO 3 will yield 21 1. of 
 laughing gas at standard conditions? 
 
 31. In the synthesis of 30 g. of ammonia, what vol- 
 ume of the components will be needed at + 13 C. and 
 900 mm. ? 
 
 32. What weight of water is required by 10 g. of 
 Mg 3 N 2 for complete decomposition, and what volume 
 of gas will be evolved ? 
 
 33. NH 4 OH, on breaking up, gives 3 1. of NH 3 at 
 C. and 760 mm. Find weight of hydroxide used. 
 
228 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 34. Sal-ammoniac is treated with 10 g. of KOH. 
 Find weights of resulting compounds. 
 
 35. If 20 g. of potassium and enough ammonia inter- 
 act, what weight and volume of hydrogen is produced? 
 
 36. What weight of salt is given by 300 cc. of HC1 
 + NH 3 ? 
 
 37. Lime water treated with 10 1. of CO 2 at standard 
 conditions will give what weight of precipitate ? 
 
 38. How much acid calcium carbonate can be pro- 
 duced from 1 Ib. of slaked lime and sufficient CO 2 ? 
 
 39. A1 4 C 3 on treatment with 12 Kg. of water will 
 give what volume of CH 4 and what weight of precipi- 
 tate? 
 
 40. To produce 3000 cc. of CH 4 , what weight of 
 sodium acetate would be needed ? 
 
 41. What volume of oxygen would be needed to burn 
 300 cc. of marsh gas ? 
 
 42. If 2 1. of oxygen are heated with carbon, what 
 volume of gas is produced at | atmospheric conditions ? 
 
 43. If 100 Ib. of chalk are treated with HC1, what 
 weight of water will be produced ? 
 
 44. Magnesium is burned in a flask containing 20 1. 
 of choke damp at C. and 760 mm. Find weight of 
 magnesium used and of carbon liberated. 
 
 45. To produce 20 1. of CO," what weights of sub- 
 stances are needed ? 
 
 46. Carbon is heated with 100 g. of oxygen. Find 
 the weight of the product. 
 
 47. How much H 2 O and CO 2 will be needed to pro- 
 duce a gram molecule of formic acid ? 
 
PROBLEMS BASED ON EQUATIONS 229 
 
 48. One ton of coke and steam reacting will give 
 what volume of gas at -f- 10 C. and 777 mm. ? 
 
 49. If 800 cc. of CO are passed over heated CuO, 
 what weight of copper is left ? 
 
 50. In the reduction of 100 tons of hematite, what 
 weight of CO will be needed and what weight of metal 
 will result ? 
 
 51. K 2 S 5 + 100 g. of HC1 will give what weight of 
 sulphur; what volume of gas ? 
 
 52. Ca 3 (PO 4 ) 2 + 3 SiO 2 + 5 C = 3 CaSiO 3 + 5 CO + 
 2 P. Find weights of products when 3 Kg. of C. are 
 used ; find volume of CO at - 40 C. and 1000 mm. 
 
 53. Arsenopyrite is roasted with 10 g. of oxygen. 
 Find volume of gas evolved and As 2 O 3 produced. 
 
 54. In the reduction of 200 g. of poisonous flour, 
 wkat weight of metal is produced ? 
 
 55. What weights of materials will be needed to 
 produce 100 Ib. of antimony ? 
 
 56. One Kg. sodium reacts on BaCl 2 . Find weight 
 of common salt produced. 
 
 57. We need 200 g. of boron; what weight of the 
 oxide and sodium will be needed ? 
 
 58. What weight of magnesium must be used to re- 
 duce 10 Kg. of B 2 O 3 ? 
 
 59. What weight of aluminum can be made from the 
 double halogen salt of aluminum when treated with 
 100 g. of sodium? 
 
 60. In the Goldschmidt alumino-thermic process, 
 what weight of materials must be used to give 100 Ib. 
 of iron ? 
 
230 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 61. If 10 g. of aluminum are treated (a) with HC1 ; 
 () with NaOH ; (<?) with KOH, what is the weight of 
 products in each case ? 
 
 62. If 300 Ib. of sand are heated with carbon, how 
 much silicon will result ; what volume of gas at +81 C. 
 and | atmosphere ? 
 
 63. If 100 1. of CO are produced in the reduction of 
 SiO 2 with C, what is the weight of metal freed ? 
 
 64. What volume of hydrogen at 2 atmospheres and 
 - 10 C. can be made from 300 g. of tin, and HC1 ? 
 
 65. What weight of tin oxide can be made by heating 
 20 g. of tin in air ? 
 
 66. If 400 g. K 2 SnO 8 are made from tin, H 2 O and 
 KOH, what is the weight of each substance used ? 
 
 67. What volume of chlorine is needed to make 300 
 g. of SnCl 4 from SnCl 2 ? 
 
 68. Galena heated with 1 Kg. of oxygen will give 
 what volume of SO 2 ; what weight of litharge ? 
 
 69. What weight of lead heated with air will produce 
 10 Ib. of lead monoxide? Find volume of air used. 
 
 70. When 30 g. of litharge and sufficient galena are 
 heated together to produce the metal, what weight of 
 products will they give? 
 
 71. If 10 g. of HC1, 20 g. of NaOH and 30 g. of 
 KOH each react on zinc, what in each case is the weight 
 of the product ? 
 
 72. Hematite is reduced by hydrogen. What weight 
 of iron can be made from 100 g. of ore ? 
 
 73. If 100 g. of cinnabar are roasted in air, what 
 weight of quicksilver results ? 
 
PROBLEMS BASED ON EQUATIONS 231 
 
 74. Iron and CO interact. Find weight of iron 
 needed to give 100 1. of oxygen. 
 
 75. If 600 g. of H 2 O 2 are made from Ba 2 O 2 , what 
 weight of oil of vitriol is needed ? 
 
 76. One 1. of ozone with H 2 O 2 gives what volume of 
 oxygen ? 
 
 77. Ag 2 O and 100 g. of H 2 O 2 will liberate what 
 weight of oxygen and of silver ? 
 
 78. What weight of iron sulphide will make 20 1. of 
 H 2 S? 
 
 79. Calcium phosphide treated with 100 g. of muri- 
 atic acid will liberate what volume of phosphine at 
 + 1C. and 766 mm.? 
 
 80. KOH + P 4 + 3 H 2 O = 3 KH 2 PO 2 + PH 3 . What 
 weight of KOH and of P are needed to give (a) 100 
 g. of PH 3 ; (6) 31 1. of PH 3 at +8 C. and 861 mm.? 
 
 81. 5 P 2 H 4 = 6 PH 3 + P 4 H 2 . Find weight of P 4 H 2 
 produced when 17 g. of PH 3 is liberated at -f 13 C. 
 and 750 mm.? 
 
 82. Arsenic is made from 3 g. of As 2 O 3 and carbon. 
 How much carbon is needed? 
 
 83. SiMg 2 + 4HCl=2MgCl 2 + SiH 4 . If 30 g. of 
 HC1 are used, find weights of the other factors in the 
 equation. 
 
 84. If 30 g. ZnCl 2 are made from ZnO, what is its 
 weight ? 
 
 85. 3 C1 2 + A1 2 O 3 + 3 C react. Find weight of A1C1 8 
 and volume of carbon monoxide if 10 g. of Cl are used. 
 
 86. Zinc is acted on by 20 1. of chlorine. What 
 weight of salt is produced ? 
 
232 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 87. A lunar caustic solution containing 20 g. is treated 
 with a " salt " solution. Find weight of residue left in 
 solution after filtering. 
 
 88. If 100 g. of iron are treated with 600 g. of iodine, 
 what weight of the iron iodide is made ? 
 
 89. In the following equation, if 1 Kg. of AgBr is 
 used, find the weight of the missing compound: 
 3FeCr 2 4 + 2 AgBr + Ag 2 Br = Fe 2 (Cr 2 O 4 ) 3 + ? + 4 Ag. 
 
 90. NaAuCl 4 + 3 Ag = NaCl + 3 AgCl -f- Au. In this 
 equation calculate the weight of gold when 100 g. of 
 silver are used. 
 
 91. 1 g. BC1 3 + water = what volume of gas and what 
 weight of B(OH) 3 ? 
 
 92. Fire damp and chlorine interact, producing tetra- 
 chlormethane and 10 1. of ,HC1. Find weights of the 
 first two substances. 
 
 93. 100 g. CC1 4 + H 2 O = what volume of CO 2 at 
 + 33C. and 555 mm.? 
 
 94. ' SiCl 4 + 4 H 2 = 4 HC1 + Si(OH) 4 . 
 
 30 g. + 80 g. ? ? 
 
 Find weights of the products and excess. 
 
 95. SiO 2 and HF interact. If 30 g. of H 2 O are pro- 
 duced, find the volume of HF used at -f 60 C. and 
 760 mm. 
 
 96. 1 g. silicon fluoride is passed into an excess of 
 water. What volume of gas and weight of solid is left ? 
 
 97. What weight of metastannic acid is given by 3 g. 
 of stannic chloride with water ? 
 
 98. What weights of SiF 4 and water result in the 
 production of 90 g. of H 2 SiF 6 ? 
 
PROBLEMS BASED ON EQUATIONS 233 
 
 99. TiCl 4 + water = what weight of TiOC] 2 when 
 2 1. of HC1 are given off ? 
 
 100. To produce 30 g. of H 2 SnO 3 , what weight of 
 SnCl 4 was used ? 
 
 101. One 1. of lead nitrate solution is treated with 
 20 g. of salt and a complete precipitation occurs. Find 
 the percentage of lead salt in the solution. 
 
 102. What weight and what volume of chlorine is 
 liberated by 100 g. of PbO 2 + HC1 ? 
 
 103. PC1 3 , AsCl 3 , BiCl 3 and SbCl 3 + excess of water 
 = what weight of the oxy chlorides when 4 1. of HC1 
 are liberated in each case ? 
 
 104. 10 g. PC1 3 + 3 H 2 O = 3 HC1 + ? 
 10 g. PC1 5 + H 2 = 2 HC1 + ? 
 10 g. POC1 3 + 3 H 2 O = 3 HC1 + ? 
 10 g. PC1 6 + 4 H 2 O = 5 HC1 + ? 
 
 In these equations find the weight of the compound 
 formed in each case. 
 
 105. 2 CuSO 4 + K 4 Fe(CN) 6 = Cu 2 Fe(CN) 6 + ? 
 
 If 100 g. of K 4 Fe(CN) 6 are taken, what weight of 
 bluestone is used, and what weight of the missing term 
 is produced? 
 
 106. Copper heated with 1 m. 3 of air will yield what 
 weight of oxide ? 
 
 107. 2 Kg. of P 2 O 6 contain what weight of P and 
 what volume oxygen ? 
 
 108. A 3 1. flask of O acts on ZnS. Find the weight 
 of products. 
 
 109. On roasting 800 g. of As 2 S 3 , what volume of O 
 is needed and what volume of gas is produced ? 
 
234 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 110. If 100 g. of CuSO 4 in solution are treated with 
 a solution of KOH and the precipitate is heated, what 
 weight of products results ? 
 
 111. Limestone is heated till all the gas is driven off. 
 It measures 109 1. Calculate the weight of gas and of 
 oxide produced. 
 
 112. What weight of oxide and of water is formed 
 by 20 g. of B(OH) 3 ? 
 
 113. Lime -f- 300 Ib. of water = what weight of cal- 
 cium hydroxide ? 
 
 114. P 2 O 5 and H 2 O interact and form 100 g. of ortho- 
 phosphoric acid. Find weight of P 2 O 5 and volume of 
 H 2 O at C. and 760 mm. 
 
 115. What weight and volume of H are liberated by 
 2 Kg. of sodium thrown on water ? 
 
 116. Ferric chloride + 30 cc. of NaOH solution (50 % ) 
 will yield what weight of precipitate ? 
 
 117. Sulphuric anhydride + a ton of water produce 
 what weight and volume of acid ? (Sp. gr. of H 2 SO 4 
 = 1.84.) 
 
 118. What weight of Na 2 O and of H 2 O are required 
 to produce 100 g. of NaOH ? 
 
 119. What weight of NaOH will be required to 
 neutralize 300 cc. N/2 H 2 SO 4 solution? 
 
 120. Na 2 O 4- 100 g. of water will form what weight 
 of caustic soda ? 
 
 121. What weight of CuS will be precipitated by 
 27 1. of H 2 S at + 20 C. and 667 mm. from excess of 
 copper solution ? 
 
 122. Green vitriol -f (NH 4 ) 2 S give 100 g. of FeS. 
 Find weights of substances used. 
 
PROBLEMS BASED ON EQUATIONS 235 
 
 123. Muriatic acid in excess reacts on 100 g. of FeS. 
 Find volume of gas evolved at 13 C. and 500 mm. 
 
 124. To slake 1 ton of lime what volume of water at 
 C. would be needed, and what weight of Ca(OH) 2 
 would be produced ? 
 
 125. From 1000 Kg. of Na 2 CO 3 , what weight of NaOH 
 can be made ? 
 
 126. To produce 100 1. of oxygen what weight of 
 Na 2 O 2 would be needed and what volume of H 2 O in 
 cc. would be used ? 
 
 127. Na 2 SO 4 + C = what weight of products, if 3 Kg. 
 of carbon are used ? 
 
 128. H 2 S and 3 g. of potassium will liberate what 
 volume of gas at + 20 C. and 777 mm. ? 
 
 129. CuO + 100 g. of H 2 SO 4 will yield what weight 
 of water ? 
 
 130. CuCl 2 with caustic soda solution containing 50 
 g. yields what weight of Cu(OH) 2 ? 
 
 131. On boiling 300 g. of copper hydroxide with 
 water, what weights of materials result ? 
 
 132. CuOH on being heated yields 10 g. of Cu 2 O ; 
 what weight of water will be formed ? 
 
 133. AuO,OH + NaOH = H 2 O + NaAuO 2 . If 41 
 g. of NaOH are used, what weight of NaAuO 2 will 
 result ? 
 
 134. A bin of lime is treated with 10 tons of water, 
 which just slakes it. A house is plastered with this 
 lime made into mortar. Find the volume of CO 2 
 needed to convert all the mortar into CaCO 3 . 
 
 135. CaSO 4 on being heated with 2 Kg. of carbon 
 yields what weights of materials ? 
 
236 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 136. When 30 g. of ZnSO 4 are treated with NaOH 
 solution, they will yield (a) what weight of Zn(OH) 2 ; 
 (6) what weight of compound when NaOH is used in 
 excess ? 
 
 137. Mercurous nitrate with 30 g. of NaOH gives 
 what weight of Hg 2 O ? 
 
 138. Hg 2 O on exposure to light yields 30 g. of mer- 
 cury. Find weight of Hg 2 O used and of residue other 
 than Hg left. 
 
 139. H 2 S is passed into a solution containing 100 g. 
 of HgCl 2 . What volume of gas is used to bring about 
 complete precipitation ? 
 
 140. KI solution containing 30 g. reacts on (a) HgNO 3 
 solution ; (b) Hg(NO 3 ) 2 solution. Find weight of re- 
 sulting salt in each case. 
 
 141. NH 4 OH, when mixed with 20 g. of A1 2 (SO 4 ) 3 in 
 solution, yields how many g. of residue ? 
 
 142. A1 2 (SO 4 ) 3 + 100 g. (NH 4 ) 2 S will produce what 
 weight of the sulphide of the metal? 
 
 143. A1 2 S 3 + excess of water gives 200 g. of A1(OH) 3 . 
 Find weight of A1 2 S 3 . 
 
 144. In the Le Blanc process what weight of mate- 
 rials can be made from 300 Kg. of common salt? 
 
 145. Sodium sulphide with 200 Kg. of powdered 
 limestone produces what weight of CaS? 
 
 146. From 10,000 1. of NH 3 -f sufficient CO 2 and 
 water, how many Kg. of sodium dicarbonate may be 
 produced? 
 
 147. Washing soda + water and 3000 1. of CO 2 at 
 8 C. and 900 mm. will produce what weight of the 
 dry product? 
 
PROBLEMS BASED ON EQUATIONS 237 
 
 148. Bicarbonate of soda with 30 1. of HC1 will gener- 
 ate what volume of gaseous product? 
 
 149. Silver nitrate with 21 g. of Na 2 CO 3 gives what 
 weight of precipitate ? 
 
 150. Washing soda reacting on 1 Kg. of sugar of lead 
 will throw down what weight of residue in solution ? 
 
 151. 3 PbC0 3 + H 2 = Pb 3 (C0 3 ) 2 (OH) 2 + C0 2 . If 
 500 1. of CO 2 are liberated, what is the weight of basic 
 salt produced? 
 
 152. What volume of HF will be needed to use up 
 20 g. of quartz, and what weight of gas will be pro- 
 duced? 
 
 153. Na 4 SiO 4 is made from SiO 2 and 300 g. of Na 2 O. 
 What weight of Na 4 SiO 4 was produced ? 
 
 154. K 4 SiO 4 , on treatment with 200 1. of HC1, pro- 
 duces what weight of orthosilicic acid and of KC1? 
 
 155. Sodium sulphide + 100 g. of SnS 2 = Na 2 SnS 3 . 
 Find weight of Na 2 S. 
 
 156. Copper + 2 Kg. of aqua fortis will yield what 
 weight of Cu(NO 3 ) 2 , and what volume of nitric oxide 
 at + 30 C. and 900 mm. ? 
 
 157. As 2 3 + 2HN0 3 + 2H 2 = 2H 3 As0 4 + ? 
 
 If 100 g. of As 2 O 3 are used, find weight and volume of 
 gas not given in equation. 
 
 158. To make 10 g. of nitrous acid, what weights of 
 N 2 O 3 and H 2 O are needed? 
 
 159. If 37 1. of oxygen are mixed with 39 1. of nitric 
 oxide, what volume of a new gas results and what 
 volume of residue is left ? 
 
 160. Lead nitrate on being heated yields 30 1. of 
 oxygen. Find weight of lead nitrate heated. 
 
238 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 161. How much HNO 3 would 100 Kg. of N 2 O 5 make 
 with water? 
 
 162. Chili saltpeter treated with 300 Kg. of H 2 SO 4 
 will yield what weight of HNO 3 ? 
 
 163. What volume of chlorine will be liberated from 
 100 g. of HC1 and enough HNO 3 to make aqua regia ; 
 and with what weight of gold will this unite ? 
 
 164. Given 300 g. of AuCl 3 , what weight of SnCl 2 
 will be required to precipitate all the gold? 
 
 165. What volume of HNO 3 (sp. gr. 1.42) will be 
 needed to dissolve 31 g. of silver and what volume of 
 gas will be evolved? 
 
 166. KC1 and NaNO 3 are allowed to act on each 
 other ; 300 Kg. of KNO 3 result. What weights of the 
 salts were used? 
 
 167. What weight of H 3 PO 3 will yield 17 1. of PH 3 ? 
 
 168. From 75 g. of P 2 O 5 + water, what weight of 
 orthophosphoric acid results? 
 
 169. A mass of apatite is treated with 100 tons of 
 H 2 SO 4 ; what weight of CaH 4 (PO 4 ) 2 will be formed? 
 
 170. One ton of Ca 3 (PO 4 ) 2 on treatment with acid 
 will produce what weight of CaSO 4 and of CaHPO 4 ? 
 
 171. P 4 + 3NaOH + 3H 2 = 3NaH 2 P0 2 + PH 3 . If 
 300 g. of phosphorus are used, what are the weights of 
 the other members of the above equation, and what is 
 the volume of the gas at 31 C. and 599 mm.? 
 
 172. H 3 AsO 4 is made from As 2 O 5 and 10 g. of water. 
 Find weight of materials used and produced. 
 
 173. Na 2 S 2 O 3 -f- 1 Kg. HC1 = what weight of sulphur 
 and what volume of SO 9 ? 
 
PROBLEMS BASED ON EQUATIONS 239 
 
 174. CuO and 750 g. of H 2 SO 4 produce what weights 
 of products? 
 
 175. One g. of Na 2 CO 3 and 1 g. of BaCl 2 are sepa- 
 rately treated with H 2 SO 4 . Find weights of products. 
 
 176. PbS is roasted with oxygen. If a ton of PbSO 4 
 is produced, what volume of oxygen has been used at 
 1 atmosphere pressure and + 26 C. ? 
 
 177. Se + 3 C1 2 + 4 H 2 = 1 Kg. of H 2 SeO 4 + 6 HC1. 
 Find weights of members on left side of equation and 
 volume of HC1 produced. 
 
 178. 2Cr(OH) 2 =21g.ofCr 2 3 + H 2 + H 2 . Cal- 
 culate the weights of solids in equation and volume of 
 gas. 
 
 179. CrCl 3 + 20 g. of caustic soda produce what 
 weight of salt and of Cr(OH) 3 ? 
 
 180. One Kg. of Cr(OH) 3 = what weight of CrO, OH 
 and of H 2 ? 
 
 181. On heating 100 g. CrO 3 , what weight of Cr 2 O 3 
 do you get and how many m. 3 of O ? 
 
 182. K 2 CrO 4 is decomposed with 1 Kg. of H 2 SO 4 . 
 Find weight of K 2 CrO 4 used and of K 2 Cr 2 O 7 produced. 
 
 183. K 2 Cr 2 O 7 is treated with 30 g. of KOH in solu- 
 tion. Find weight of material used and produced. 
 
 184. Na 2 Cr 2 O 7 is changed by 10 g. of KC1 into 
 K 2 O 2 O 7 . Find weight of NaCl produced. 
 
 185. On heating 1 Kg. of K 2 Cr 2 O 7 , what weights of 
 normal chromate, Cr 2 O 3 , and volume of oxygen do you 
 get? 
 
 186. Oil of vitriol with 376 g. of K 2 Cr 2 O 7 produces 
 what weights of materials and what volume of gas at 
 -22C. and941mrn.? 
 
240 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 187. Cr 2 (SO 4 ) 3 + 23 g. of (NH 4 ) 2 S will produce what 
 weight of Cr 2 S 3 and of ammonium sulphate ? 
 
 188. Cr 2 S 3 , on treatment with 99 cc. of H 2 O at C. 
 and 760 mm., yields what weight of substances? 
 
 189. Sugar of lead + 10 g. of K 2 Cr 2 O 7 = how much 
 precipitate ? A lead salt + 32 g. of K 2 CrO 4 produces 
 what weight of lead chromate ? 
 
 190. One Kg. of corrosive sublimate is made from 
 what weights of HgO and chlorine? 
 
 191. To make 30 g. of HOC1, how much C1 2 O and 
 H 2 O must be used ? 
 
 192. C1 2 + H 2 O = HC1 + HOC1. If 21 1. of chlorine 
 at + 8 C. and 600 mm. are used, find volume of HC1 
 produced at standard conditions. 
 
 193. HgO, water, and 333 1. of chlorine are placed in 
 a vessel. How many g. of HgCl 2 and of HOC1 were 
 produced ? 
 
 194. Through a KOH solution is passed 13 1. of 
 chlorine. Find the weight of KOC1 made. 
 
 195. If 3 tons of slaked lime are treated with chlorine, 
 what is the weight of bleaching powder produced? 
 
 196. Given 25 g. of HOC1, what volumes of HC1 and 
 of O are produced when it is exposed to sunlight ? 
 
 197. HOC1+ 3 g. of HC1 give what weight of chlo- 
 rine and of water? 
 
 198. CaCl(OCl) 4- 8 g. of H 2 SO 4 = what weight of 
 CaSO 4 and of HOC1? 
 
 199. 2 CaCl(OCl) + H 2 O + CO 2 = CaCO 3 + CaCl 2 -h 
 2 HOC1. If 13 1. of CO 2 are used, find weight in g. of 
 resulting substances. 
 
PROBLEMS BASED ON EQUATIONS 241 
 
 200. When 13 g. of NH 3 react on NaBrO, what vol- 
 ume of nitrogen is given off? 
 
 201. 3 NaBrO + 100 g. CO(NH 2 ) 2 = what weight of 
 NaBr, H 2 O, N, and CO 2 ? 
 
 202. 3 HOC1 = HOC1O 2 + 2 HC1. If 41 1. of HC1 
 are produced, what is the weight of HOC1 used? 
 
 203. Should 30 g. of KOC1 break up, find weight of 
 KOC1O 2 and of KC1 produced. 
 
 204. In the making of KC1O 3 , 100 1. of chlorine were 
 passed through a solution containing 300 g. of KOH. 
 Find the weight of KC1O 3 made and of the substance in 
 excess. 
 
 205. Ca(ClO 3 ) 2 + 100 g. of KC1 = what weight of 
 CaCl 2 and of KC1O 8 ? 
 
 206. One Kg. of barium chlorate is treated with H 2 SO 4 
 in excess. Find weight of precipitate and of HC1Q 3 . 
 
 207. HC1O 3 + 5 g. of HC1 = what weight of H 2 O 
 and of chlorine ? 
 
 203. To make 100 g. of HC1O 3 , what weights of C1 2 O 5 
 and of water are needed? 
 
 209. C1 2 O 4 + 30 g. H 2 O = how many g. of HC1O 3 and 
 ofHC10 2 ? 
 
 210. We need 80 g. of HC1O 2 . How much C1 2 O 3 
 must be dissolved in water to produce it ? 
 
 211. Should one need to make 30 g. of HIO 3 , what 
 weight of I 2 O 5 and of H 2 O are needed ? 
 
 212. 2HI0 3 +5S0 2 + 4H 2 = 5H 2 S0 4 + I 2 . To 
 produce 30 g. of iodine what volume of SO 2 at 9 C. 
 and 861 mm. should be used ? 
 
 213. 2 HC1O 3 =HC1O 2 + HC1O 4 . Should 20 g. of 
 HC1O 3 be used, what weight of HC10 2 will result ? 
 
242 PROGRESSIVE PROBLEMS IN CHEMISTRY 
 
 214. Ba(ClO 4 ) 2 + 10 cc. of H 2 SO 4 (sp. gr. = 1.84) 
 will produce what weight of residue and of HC1O 4 ? 
 
 215. If 77 g. of KC1O 3 are heated just to fusion, 
 what weights of KC1O 4 , KC1, and O will result ? 
 
 216. 1 g. HC1O 4 on treatment with iodine yields how 
 manyg. of HIO 4 andCl? 
 
 217. To make 39 g. of Mn(OH) 2 what weight of 
 MnCl 2 must be taken and how many cc. of a 40 % 
 NaOH solution will be needed ? 
 
 218. Mn 2 (SO 4 ) 3 + 90 cc. of NaOH (25 % solution) 
 will yield how many g. of Mn(OH) 3 and of Na 2 SO 4 ? 
 
 219. To produce 21 1. of oxygen, what weights of 
 KMnO 4 and of H 2 SO 4 are required ? 
 
 220. 2 KMnO 4 + 10 FeSO 4 + 8 H 2 SO 4 
 
 = K 2 SO 4 + 2 MnSO 4 + ? + ? 
 
 Should 800 g. of KMnO 4 be used, find weights of 
 missing terms in the above equation. 
 
 221. To make 31 g. of H 2 SO 4 what weights of 
 KMnO 4 , SO 2 , and H 2 O are required ? 
 
 222. 2 KMn0 4 + 5 H 2 O 2 + 3 H 2 SO 4 
 
 == ? + ? + 8H 2 + 5O 2 . 
 
 If 13 g. of H 2 O 2 are used, what weights of missing 
 members of equation and 1. of oxygen are produced ? 
 
 223. 2 KMnO 4 + 5 C 2 H 2 O 4 + 3 H 2 SO 4 
 
 = ? + ? + 10 CO 2 + 8 H 2 O. 
 
 If 20 g. of CO 2 are produced, calculate the weight of 
 KMnO 4 used and of missing factors in equation. 
 
 224. 10 g. manganese chloride with (NH 4 ) 2 S yields 
 how many g. of NH 4 C1 and of MnS ? 
 
 225. Ferric sulphate with 300 g. of caustic soda in 
 solution produces what mass of ferric hydroxide ? 
 
PROBLEMS BASED ON EQUATIONS 243 
 
 226. From 80 g. of ferrous sulphate + (NH 4 ) 2 S what 
 mass of FeS will result ? 
 
 227. To make 3 tons of CaC 2 what weights of lime 
 and C are needed? 
 
 228. A million m. 3 of C 2 H 2 are required. How 
 many Kg. of materials will be used and what weight 
 of residue will be left? 
 
 229. BN + 3 H 2 O = B(OH) 3 + NH 3 . To produce 
 80 cc. of NH 3 what weight of BN must be taken ? 
 
 230. NaNH 2 + 31 cc. of H 2 O will give what weight 
 of NaOH and what volume in 1. of NH 3 at + 31 C. 
 and 800 mm. pressure? 
 
 231. Mercuric cyanide on being heated breaks up 
 into 3 g. of Hg and (CN) 2 ; what weight was heated ? 
 
 232. Potassium cyanide on treatment with 2 g. H 2 SO 4 
 gives what volume of HCN at + 17 C. and 770 mm. ? 
 
 233. From 2 Kg. of CaCN 2 + H 2 O how many g. of 
 Ca(OH) 2 andof H 2 CN 2 ? 
 
 234. K 4 Fe(CN) 6 is reduced with 30 g. of K. What 
 weight of Fe and of KCN are left ? 
 
 235. Litharge + 1 g. of KCN = what weight of Pb 
 and of KCNO ? 
 
 236. KCN and 3 g. of AgNO 3 will give what mass of 
 saltpeter and of AgCN? 
 
 237. 3 K 4 Fe(CN) 6 + 4 FeCl 3 = Prussian blue + 12 
 KC1. Should 8 g. of FeCl 3 be used, find the weight 
 of Prussian blue produced. 
 
 238. 2 K 3 Fe(CN) 6 + 3 FeSO 4 = 3 K 2 SO 4 + Turnbull's 
 blue. What weight of Turnbull's blue can be made 
 from 81 g. of FeSO 4 ? 
 
APPENDIX 
 
 I. INTERNATIONAL ATOMIC WEIGHTS, 1911 
 
 Aluminium 
 Antimony 
 
 Symbol 
 . . . . Al 
 Sb 
 
 Atomic 
 Weight 
 27.1 
 120.2 
 
 Molybdenum . . . 
 Neody mi um 
 
 Symbol 
 . Mo 
 . Nd 
 
 Atomic 
 Weight 
 96.0 
 144 3 
 
 Argon 
 
 A. 
 
 39 88 
 
 Neon ... . 
 
 Ne 
 
 20 2 
 
 Arsenic 
 
 As 
 
 74 96 
 
 Nickel 
 
 Ni 
 
 58 68 
 
 
 Ba 
 
 137 37 
 
 
 N 
 
 14 01 
 
 Bismuth 
 
 . . . . Bi 
 
 208.0 
 
 Osmium 
 
 . Os 
 
 190.9 
 
 Boron 
 
 ... B 
 
 11.0 
 
 Oxvsren 
 
 . O 
 
 16 00 
 
 Bromine 
 
 Br 
 
 79 92 
 
 Palladium . 
 
 Pd 
 
 106 7 
 
 Cadmium . 
 
 . . . . Cd 
 
 112.40 
 
 Phosphorus 
 
 . p 
 
 31.04 
 
 
 Cs 
 
 132 81 
 
 
 Pt 
 
 195 2 
 
 Calcium . 
 
 . . . . Ca 
 
 40.09 
 
 Potassium . . . . 
 
 . K 
 
 39.10 
 
 Carbon 
 
 . . C 
 
 12 
 
 Praseodymium 
 
 . Pr 
 
 140 6 
 
 
 Ce 
 
 140 25 
 
 Radium 
 
 Ra 
 
 226 4 
 
 
 Cl 
 
 35 46 
 
 
 Rh 
 
 102 9 
 
 Chromium 
 
 . . . Cr 
 
 52.0 
 
 Rubidium . 
 
 . Rb 
 
 85.45 
 
 Cobalt 
 
 . Co 
 
 58.97 
 
 Ruthenium 
 
 Ru 
 
 101 7 
 
 Columbium . 
 
 . . . . Cb 
 
 93.5 
 
 Samarium .... 
 
 . Sa 
 
 150.4 
 
 Copper 
 
 . . . . Cu 
 
 63.57 
 
 Scandium . . . . 
 
 . Sc 
 
 44.1 
 
 Dysprosium 
 
 . Dy 
 
 162.5 
 
 Selenium .... 
 
 . Se 
 
 79.2 
 
 Erbium 
 
 . . . . Er 
 
 167.4 
 
 Silicon 
 
 . Si 
 
 28.3 
 
 Europium 
 
 . Eu 
 
 152.0 
 
 Silver 
 
 As 
 
 107 88 
 
 Fluorine . . 
 
 . . . . F 
 
 19.0 
 
 Sodium 
 
 . Na 
 
 23.00 
 
 Gadolinium 
 
 . . . . Gd 
 
 157.3 
 
 Strontium . 
 
 . Sr 
 
 87.63 
 
 Gallium . 
 
 . . . . Ga 
 
 69.9 
 
 Sulphur 
 
 . S 
 
 32.07 
 
 Germanium 
 
 ... Ge 
 
 72 5 
 
 
 Ta 
 
 181 
 
 Glucinum 
 
 Gl 
 
 9 1 
 
 Tellurium 
 
 Te 
 
 127 5 
 
 Gold 
 
 Au 
 
 197 2 
 
 Terbium 
 
 Tb 
 
 159 2 
 
 Helium . 
 
 .... He 
 
 3 99 
 
 Thallium 
 
 . Tl 
 
 204.0 
 
 Hydrogen 
 
 . . H 
 
 1 008 
 
 
 Th 
 
 232 4 
 
 Indium . 
 
 In 
 
 114 8 
 
 Thulium 
 
 Tm 
 
 168 5 
 
 Iodine 
 
 I 
 
 126 92 
 
 Tin 
 
 Sn 
 
 119 
 
 Iridium . 
 
 . . . . Ir 
 
 193.1 
 
 Titanium .... 
 
 . Ti 
 
 48.1 
 
 Iron . . . 
 
 . . . . Fe 
 
 55 85 
 
 Tungsten 
 
 . W 
 
 184.0 
 
 Krypton 
 
 ... Kr 
 
 82 92 
 
 
 . U 
 
 238.5 
 
 Lanthan um 
 
 . . . La 
 
 1390 
 
 Vanadium .... 
 
 . V 
 
 51.06 
 
 Lead 
 
 . . Pb 
 
 207 10 
 
 
 . Xe 
 
 130.2 
 
 Lithium 
 
 Li 
 
 6 94 
 
 
 
 
 
 Lu 
 
 1740 
 
 (Neo-ytterbium) 
 
 . Yb 
 
 1720 
 
 Magnesium . 
 
 . Mg 
 
 24.32 
 
 Yttrium 
 
 . Yt 
 
 89.0 
 
 Manganese 
 
 . . . . Mn 
 
 54.93 
 
 Zinc 
 
 . Zn 
 
 65.37 
 
 Mercury . 
 
 . Hff 
 
 200.0 
 
 Zirconium . 
 
 . Zr 
 
 90.6 
 
 245 
 
246 
 
 APPENDIX 
 
 > 
 
 I o 
 o w 
 
 ~ 
 
 pou9< 
 
 * I 1 s S 3 
 
 oil* I I 
 
 ^ , S w 2 s. ' 
 
 i ? s i si i 
 
 5 is 
 
 !!?! 11 f 
 
 US 
 
 en 
 
 ^ ii 
 
 a ' 
 
 I 
 
 7 
 
 <D II 
 
 W M 
 
 i i 
 
APPENDIX 
 
 247 
 
 III. THE METRIC SYSTEM 
 
 The fundamental unit of the metric system is the Meter (the unit of 
 length). From this the units of mass (Gram) and capacity (Liter) are 
 derived. All other units are the decimal subdivisions or multiples of 
 these. These three units are simply related, so that for all practical 
 purposes the volume of one kilogram of water (one liter) is equal to 
 one cubic decimeter. 
 
 PREFIXES 
 
 
 MEANING 
 
 
 UNITS 
 
 Milli- 
 
 = one thousandth 
 
 T^OlT 
 
 .001 
 
 
 Centi- 
 
 = one hundredth 
 
 TtfTF 
 
 .01 
 
 
 Deci- 
 
 = one tenth 
 
 A 
 
 .1 
 
 Meter for length 
 
 unit 
 
 = one 
 
 
 1. 
 
 Gram for mass 
 
 Deka- 
 
 = ten 
 
 
 
 10. 
 
 Liter for capacity 
 
 Hecto- 
 
 = one hundred 
 
 10.Q 
 
 100. 
 
 
 Kilo- 
 
 = one thousand 
 
 io T <m 
 
 1000. 
 
 
 The metric terms are formed by combining the words "Meter," 
 Liter " with the six numerical prefixes. 
 
 Length 
 
 10 milli-meters mm. = 1 centi-meter 
 
 10 centi-meters 
 10 deci-meters 
 10 meters 
 10 deka-meters 
 10 hecto-meters 
 
 = 1 deci-meter 
 
 = 1 Meter (about 40 inches) 
 
 = 1 deka-meter 
 
 = 1 hecto-meter 
 
 = 1 kilo-meter (about f- mile) 
 
 ; Gram," and 
 
 em. 
 
 dm. 
 
 m. 
 
 dkm. 
 hm. 
 km. 
 
 Mass 
 
 mg. = 1 centi-gram eg. 
 
 = 1 deci-gram dg. 
 
 = 1 Gram (about 15 grains) g. 
 
 = 1 deka-gram dkg. 
 
 = 1 hecto-gram hg. 
 
 = 1 kilo-gram (about 2 pounds) kg. 
 
 Capacity 
 
 = 1 centi-liter cl. 
 
 = 1 deci-liter dl. 
 
 = 1 Liter (about 1 quart) 1. 
 
 = 1 deka-liter dkl. 
 
 = 1 hecto-liter (about a barrel) hi. 
 
 = 1 kilo-liter kl. 
 The square and cubic units are the squares and cubes of the linear units. 
 The ordinary unit of land area is the " Hectare " (about 2 acres). 
 
 10 milli-grams 
 10 centi-grams 
 10 deci-grams 
 10 grams 
 10 deka-grams 
 10 hecto-gram s 
 
 10 milli-liters 
 10 centi-liters 
 10 deci-liters 
 10 liters 
 10 deka-liters 
 10 hecto-liters 
 
 ml. 
 
248 
 
 APPENDIX 
 
 EQUIVALENTS 
 1 Meter = 39.37 Inches 
 
 Legal equivalent adopted by Act of Congress, July 28, 1866 
 
 Length 
 
 Centimeter 
 
 = 0.3937 
 
 inch 
 
 Meter 
 
 = 3.28 
 
 feet 
 
 Meter 
 
 = 1.094 
 
 yards 
 
 Kilometer 
 
 = 0.621 
 
 statute mile 
 
 Kilometer 
 
 = 0.5396 
 
 nautical mile 
 
 Inch 
 
 = 2.540 
 
 centimeters 
 
 Foot 
 
 = 0.305 
 
 meter 
 
 Yard 
 
 = 0.914 
 
 meter 
 
 Statute mile 
 
 = 1.61 
 
 kilometers 
 
 Nautical mile 
 
 = 1.853 
 
 kilometers 
 
 Area 
 
 Sq. centimeter 
 Sq. meter 
 Sq. meter 
 Hectare 
 Sq. kilometer 
 
 Sq. inch 
 Sq. foot 
 Sq. yard 
 Acre 
 Sq. mile 
 
 0.155 sq. inch 
 
 10.76 sq. feet 
 
 1.196 sq. yards 
 
 2.47 acres 
 
 0.386 sq. mile 
 
 6.45 sq. centimeters 
 
 0.0929 sq. meter 
 
 0.836 sq. meter 
 
 0.405 hectare 
 
 2.59 sq. kilometers 
 
 Volume 
 
 Cu. centimeter = 0.0610 cu. inch 
 Cu. meter = 35.3 cu. feet 
 Cu. meter = 1.308 cu. yards 
 
 Cu. inch = 16.39 cu. centimeter 
 
 Cu. foot = 0.0283 cu. meter 
 
 Cu. yard = 0.765 cu. meter 
 
APPENDIX 
 
 249 
 
 EQUIVALENTS Continued 
 Capacity 
 
 Milliliter 
 
 = 0.0338 U. S. liq. ounce 
 
 Milliliter 
 
 = 0.2705 U. S. apoth. dram 
 
 Liter 
 
 = 1.057 U. S. liq. quarts 
 
 Liter 
 
 = 0.2642 U. S. liq. gallon 
 
 Liter 
 
 .= 0.908 U. S. dry quart 
 
 Dekaliter 
 
 = 1.135 U. S. pecks 
 
 Hectoliter 
 
 = 2.838 U. S. bushels 
 
 U. S. liq. ounce 
 
 = 29.57 milliliters 
 
 U. S. apoth. dram 
 
 = 3.70 milliliters 
 
 U. S. liq. quart 
 
 = 0.946 liter 
 
 U. S. dry quart 
 
 = 1.101 liters 
 
 U. S. liq. gallon 
 
 = 3.785 liters 
 
 U. S. peck 
 
 = 0.881 dekaliter 
 
 U. S. bushel 
 
 = 0.3524 hectoliter 
 
 Weight 
 
 Gram 
 
 = 15.43 grains 
 
 Gram 
 
 = 0.772 U. S. apoth. scruple 
 
 Gram 
 
 = 0.2572 U. S. apoth. dram 
 
 Gram 
 
 = 0.0353 avoir, ounce 
 
 Gram 
 
 = 0.03215 troy ounce 
 
 Kilogram 
 
 = 2.205 avoir, pounds 
 
 Kilogram 
 
 = 2.679 troy pounds 
 
 Metric ton 
 
 = 0.984 gross or long ton 
 
 Metric ton 
 
 = 1.102 short or net tons 
 
 Grain 
 
 = 0.0648 gram 
 
 U. S. apoth. scruple 
 
 = 1.296 grams 
 
 U. S. apoth. dram 
 
 = 3.89 grams 
 
 Avoir, ounce 
 
 = 28.35 grams 
 
 Troy ounce 
 
 = 31.10 grams 
 
 Avoir, pound 
 
 = 0.4536 kilogram 
 
 Troy pound 
 
 = 0.373 kilogram 
 
 Gross or long ton 
 
 = 1.016 metric tons 
 
 Short or net ton 
 
 = 0.907 metric ton 
 
250 
 
 APPENDIX 
 
 Area of triangle 
 Area of triangle 
 
 Mensuration Rules 
 
 = \ (base x altitude). 
 
 Area of parallelogram 
 Area of trapezoid 
 Circumference of circle 
 
 Diameter of circle 
 
 Area of circle 
 
 Area of ellipse 
 Area of regular polygon 
 Lateral surface of cylinder 
 Volume of cylinder 
 
 Surface of sphere 
 
 Volume of sphere 
 
 Surface of pyramid \ 
 Surface of cone J 
 Volume of cone 
 
 = Vs (s a) (s 6) (s - c) , where 
 
 s= i( + & + C ). 
 = base x altitude. 
 
 = altitude x | sum of parallel sides. 
 = diameter x 3.1416. 
 _ ( circumference -=-3.1416. 
 ~ I circumference x 0.3183. 
 
 ( diameter squared x 0.7854. 
 ~ I radius squared x 3.1416. 
 = product of diameters x 0.7854. 
 = (sum of sides x apothem). 
 
 circumference of base x altitude. 
 
 area of base x altitude. 
 
 f diameter x circumference. 
 
 \4 x 3.1416 x square of radius. 
 
 f diameter cubed x 0.5236. 
 
 A | of radius cubed x 3.1416. 
 
 I (circumference of base x slant 
 
 height) . 
 
 \ (area of base x altitude) . 
 
APPENDIX 
 
 251 
 
 IV. SPECIFIC GRAVITY OF GASES* 
 
 Name 
 
 Formula 
 
 Molecu- 
 lar 
 Weight 
 
 Specific Gravity, 
 Air = 1 
 
 Weight in 
 Grams of 1 
 Liter at 0, 
 760 mm. at 
 Sea Level, 
 lat. 45. 
 
 Calcu- 
 lated 
 
 Observed 
 
 Acetylene .... 
 Air 
 Ammonia .... 
 
 C 2 H 2 
 
 NH 3 
 A 
 AsH 3 
 Br 2 
 C 4 H 10 
 C0 2 
 CO 
 COS 
 C1 2 
 C 2 N 2 
 C 2 H 6 
 C 2 H 4 
 F 2 
 He 
 HBr 
 HC1 
 HF 
 HI 
 H 2 
 H 2 Se 
 H 2 S 
 H 2 Te 
 Kr 
 CH 4 
 Ne 
 NO 
 N 2 
 N 2 
 N 2 +A etc. 
 N0 2 
 N 2 4 
 NOC1 
 2 
 PH 3 
 C 3 H 6 
 SiF 4 
 S0 2 
 X 
 
 26.016 
 
 17.064 
 39.9 
 78.024 
 159.92 
 58.08 
 44.00 
 28.00 
 60.06 
 70.90 
 52.08 
 30.048 
 28.032 
 38.0 
 4 
 80.968 
 36.458 
 20.008 
 127.98 
 2.016 
 81.216 
 34.076 
 129.62 
 81.8 
 16.032 
 20 
 30.04 
 44.08 
 28.08 
 
 46.04 
 92.08 
 65.49 
 32.00 
 34.024 
 42.048 
 104.4 
 64.06 
 128 
 
 0.8988 
 1.0000 
 0.5895 
 1.379 
 2.696 
 5.5249 
 2.0065 
 1.5201 
 0.9673 
 2.0749 
 2.489 
 1.7993 
 1.0381 
 0.9784 
 1.313 
 0.1382 
 2.7973 
 1.2595 
 0.691 
 4.4172 
 0.06965 
 2.806 
 1.1773 
 4.478 
 2.826 
 0.5539 
 0.691 
 1.0378 
 1.5229 
 0.9701 
 
 1.5906 
 3.1812 
 2.2625 
 1.1055 
 1.175 
 1.4527 
 3.607 
 2.2131 
 4.422 
 
 0.92 
 
 0.5971 
 1.379 
 2.695 
 5.524(227.9) 
 2.01 
 1.52909 
 0.96716 
 2.1046 
 2.491 
 1.8064 
 1.075 
 0.9852 
 1.26 
 0.1368 
 2.71 
 1.2692 
 0.7126 
 4.3757 
 0.06960 
 2.795 
 1.1895 
 4.489 
 2.818 
 0.5576 
 0.674 
 1.0367 
 1.5301 
 0.96737 
 0.97209 
 1.60 (135) 
 2.65 (26.7) 
 2.31 
 1.10535 
 1.214 
 1.498 
 3.60 
 2.2639 
 4.422 
 
 1.1620 
 1.29330 
 0.7621 
 1.7828 
 3.485 
 7.1426 
 2.594 
 1.9652 
 1.2506 
 2.6825 
 3.1666 
 2.3261 
 1.3421 
 1.2520 
 1.697 
 0.1787 
 3.6163 
 1.6283 
 0.894 
 5.7106 
 0.089873 
 3.627 
 1.5230 
 5.789 
 3.654 
 0.7160 
 0.893 
 1.3402 
 1.9688 
 1.2542 
 1 .25718 
 2.0563 
 4.1126 
 2.925 
 1.4290 
 1.520 
 1.8780 
 4.663 
 2.8611 
 5.717 
 
 Arsine 
 
 Bromine .... 
 
 Carbon dioxide . . 
 Carbon monoxide . 
 Carbon oxysulphide 
 Chlorine .... 
 Cyanogen .... 
 Ethane . . . 
 
 Ethylene .... 
 Fluorine .... 
 Helium 
 
 Hydrobromic acid . 
 Hydrochloric acid . 
 Hydrofluoric acid . 
 Hydroiodic acid . . 
 Hydrogen .... 
 Hydrogen selenide . 
 Hydrogen sulphide . 
 Hydrogen telluride . 
 Krypton .... 
 Methane .... 
 Neon 
 
 Nitric oxide . . . 
 Nitrous oxide . . . 
 Nitrogen .... 
 atmospheric . . 
 Nitrogen dioxide 
 Nitrogen dioxide 
 Nitrosyl chloride 
 Oxvfiren 
 
 Phosphine .... 
 Propylene .... 
 Silicon fluoride . . 
 Sulphur dioxide . . 
 Xenon . . 
 
 
 * Quoted from Landolt-Bornstein. Phys.-Chem. Tabellen, 1905, p. 
 with revisions by Olsen. 
 
 222, 
 
252 
 
 APPENDIX 
 
 V. PHYSICAL CONSTANTS 
 
 [ Number j ] 
 
 Name 
 
 Sym- 
 bol 
 
 Atomic 
 Weight 
 O = 16 
 
 Molec- 
 ular 
 Weight 
 
 Specific 
 Gravity 
 Water =1 
 Air=l (A) 
 Hydrogen = 
 1 (D) 
 
 \tomic 
 Vol. 
 At.Wt. 
 
 Specific 
 Heat 
 at C. 
 
 8p. Gr. 
 
 1 
 
 Aluminium . . 
 
 Al 
 
 27.1 
 
 
 2.5834 
 
 10.5 
 
 .2220 
 
 2 
 
 Antimony . . . 
 
 Sb 
 
 120.2 
 
 
 6.62 
 
 18.2 
 
 .0495 
 
 8 
 
 Argon, gas . . 
 
 A 
 
 39.9 
 
 39.9 
 
 (1.379 A 
 I 19.96 D 
 
 
 .1233 
 
 4 
 
 liquid .... 
 
 A 
 
 39.9 
 
 
 1.4046-1860 
 
 28.5 
 
 
 5 
 
 Arsenic, amorph. 
 
 As 
 
 75.0 
 
 300 
 
 4.7161 40 
 
 15.9 
 
 .0758 { 21- 
 
 6 
 
 cryst 
 
 As 
 
 75.0 
 
 300 
 
 5.727 140 
 
 13.2 
 
 .0830 I 65 
 
 7 
 
 Barium .... 
 
 Ba 
 
 137.4 
 
 
 3.75 
 
 36.7 
 
 
 8 
 
 Bismuth . . . 
 
 Bi 
 
 208.5 
 
 
 9.7474 
 
 21.4 
 
 .03013 
 
 9 
 
 Boron, amorph. . 
 
 B 
 
 11.0 
 
 
 2.45 
 
 4.5 
 
 .3066 
 
 10 
 
 cryst 
 
 B 
 
 11.0 
 
 
 2.53-2.68 
 
 4.2 
 
 
 11 
 
 Bromine, gas . . 
 
 Br 2 
 
 79.96 
 
 159.92 
 
 5.869160 A 
 
 
 .0555(83) 
 
 12 
 
 liquid. . . . 
 
 Br 2 
 
 79.96 
 
 159.92 
 
 3.18830 
 
 25 
 
 .1071 
 
 13 
 
 Cadmium . . . 
 
 Cd 
 
 112.4 
 
 112.4 
 
 8.64217 
 
 13 
 
 .0548 
 
 14 
 
 Caesium .... 
 
 Cs 
 
 132.9 
 
 
 2.366 
 
 56 
 
 .04817 
 
 in 
 
 CalSium . . . 
 
 Ca 
 
 40.1 
 
 
 1.544629.20 
 
 26 
 
 .1804 
 
 1(5 
 
 Carbon, amorph. 
 
 C 
 
 12.00 
 
 
 1.75-2.10 
 
 6.0 
 
 .241 
 
 17 
 
 graphite . . . 
 
 C 
 
 12.00 
 
 
 2.10-2.585 
 
 5 
 
 .202 
 
 IS 
 
 diamond . . . 
 
 C 
 
 12.00 
 
 
 3.47-3.5585 
 
 3.4 
 
 .1469 
 
 19 
 
 Cerium .... 
 
 Ce 
 
 140.25 
 
 
 7.0424 
 
 20 
 
 .04479 
 
 20 
 
 Chlorine, gas . . 
 
 Cl 
 
 35.45 
 
 70.90 
 
 2.491A 
 
 
 .1241 
 
 21 
 
 liquid .... 
 
 Cl 
 
 35.45 
 
 
 1.44050 
 
 24.6 
 
 .2262 
 
 22 
 
 Chromium . . . 
 
 Cr 
 
 52.1 
 
 
 6.9220 
 
 7.6 
 
 .10394 
 
 23 
 
 Cohalt . [bium) 
 
 Co 
 
 59.0 
 
 
 8.718H 
 
 6.8 
 
 .1030 
 
 24 
 
 Columbium (Nio- 
 
 Cb 
 
 94.0 
 
 
 7.06i| 
 
 13.3 
 
 
 25 
 
 Copper .... 
 
 Cu 
 
 63.6 
 
 
 8.91-8.96 
 
 7.1 
 
 .0936 
 
 21 i 
 
 Erbium .... 
 
 Er 
 
 166 
 
 
 4.77 
 
 34.8 
 
 
 27 
 
 Fluorine, gas . . 
 
 F 
 
 19 
 
 38 
 
 1.31i5A 
 
 
 
 28 
 
 liquid .... 
 
 F 
 
 19 
 
 38 
 
 1.14-1870 
 
 16.7 
 
 
 2<> 
 
 Gadolinium . . 
 
 Gd 
 
 156 
 
 
 1.31 
 
 119.1 
 
 
 ;io 
 
 Gallium . . . 
 
 Ga 
 
 70 
 
 
 5.9524 
 
 11.8 
 
 .079 
 
 31 
 
 Germanium . . 
 
 Ge 
 
 72.5 
 
 
 5.469| 
 
 13.3 
 
 .0737 
 
 :52 
 
 Glucinum (Beryl- 
 
 Gl 
 
 9.1 
 
 
 1.85 20 A 
 
 4.9 
 
 
 x; 
 
 Gold . . [Hum) 
 
 Au 
 
 197.2 
 
 
 19.32 
 
 10.2 
 
 .0316 
 
 ;u 
 
 Helium, gas . . 
 
 He 
 
 4 
 
 4 
 
 C 0.1368 A 
 1 1.98 D 
 
 
 
 *From Van Nost rand's Chemical Annual Olsen. 
 f K = the number of grams of water which can be raised from to 1 C. 
 by the heat which passes through a cubic centimeter of the substance in 
 
APPENDIX 
 
 253 
 
 OF THE ELEMENTS* 
 
 Number 
 
 ||? 
 
 Electrical 
 Conduc- 
 tivity 
 at C. 
 
 Thermal 
 Conduc- 
 tivity 
 Kt at C. 
 Ag- = 1.00 
 
 Linear 
 Coefficient of 
 Expansion 
 
 Melting 
 Point, 
 
 Boiling 
 Point, 
 
 1 
 
 6.02 
 
 324000 
 
 .3435 
 
 .0 4 2313 
 
 AtC. 
 40 
 
 657 
 
 1470-1700 
 
 2 
 
 5.95 
 
 27100 
 
 .0442 
 
 .0 4 1152 
 
 40 
 
 630 
 
 1500-1700 
 
 3 
 
 4.92 
 
 
 .0 4 3894 
 
 
 
 187.9 
 
 - 186.1 
 
 4 
 
 
 
 
 
 
 
 
 6 
 
 5.69 
 
 28600 
 
 
 .0 4 0559 
 
 40 
 
 
 <360 
 
 6 
 
 6.23 
 
 
 
 
 
 sublimes at 
 
 449* 
 
 7 
 
 
 
 
 
 
 850 
 
 vol. 950 
 
 8 
 
 6.28 
 
 9260 
 
 .0177 
 
 .0 4 1346 
 
 40 
 
 269 
 
 1435 
 
 1) 
 
 3.37 
 
 
 
 
 
 infusible 
 
 sublimes at 
 
 10 
 
 
 
 
 
 
 infusible 
 
 3500 
 
 11 
 
 4.44 
 
 
 
 
 
 
 
 12 
 
 8.57 
 
 
 
 
 
 -7.3 
 
 59 
 
 13 
 
 6.16 
 
 146000 
 
 .2213 
 
 .0 4 3069 
 
 40 
 
 321.7 
 
 778 
 
 14 
 
 6.41 
 
 25400 
 
 
 .0 3 39482 
 
 27-100 
 
 26.37 
 
 670 
 
 15 
 
 7.23 
 
 95000 
 
 
 
 
 780-810 
 
 
 16 
 
 2.89 
 
 
 
 .0 4 054 
 
 40 
 
 sublimes 
 
 3500 
 
 17 
 
 2.22 
 
 
 
 .0 4 0786 
 
 40 
 
 sublimes 
 
 3500 
 
 18 
 
 1.76 
 
 
 
 .0 4 0118 
 
 40 
 
 sublimes 
 
 3500 
 
 19 
 
 6.28 
 
 
 
 
 
 623 
 
 
 20 
 
 4.40 
 
 
 
 
 
 -102 
 
 - 33.6 
 
 21 
 
 8.02 
 
 
 
 2 1978 
 
 0-10 
 
 
 
 22 
 
 5.42 
 
 
 
 
 
 1515 
 
 
 23 
 
 6.08 
 
 83200 
 
 
 .0 4 1236 
 
 40 
 
 1530 
 
 
 24 
 
 
 
 
 
 
 1950 
 
 
 25 
 
 5.95 
 
 640600 
 
 .7198 
 
 .0 4 1678 
 
 40 { 
 
 1084 
 1065(inair) 
 
 2100 
 
 27 
 
 
 
 
 
 
 223 
 
 187 
 
 28 
 
 
 
 
 
 
 223 
 
 187 
 
 29 
 
 
 
 
 
 
 
 
 30 
 
 5.53 
 
 
 
 
 
 30.15 
 
 
 31 
 
 5.34 
 
 
 
 
 
 900 
 
 vol. 1350 
 
 32 
 
 
 
 
 
 
 >960 
 
 
 33 
 
 6.23 
 
 468000 
 
 .7003 
 
 .0 4 1470 
 
 0-100 
 
 1065 
 
 
 34 
 
 
 
 .0 3 3386 
 
 
 
 < - 271.3 
 
 -267 
 
 one second when the temperatures of the opposite sides of the cube are 
 maintained at a difference of 1 C. 
 
254 
 
 APPENDIX 
 
 Number || 
 
 Name 
 
 Sym- 
 bol 
 
 Atomic 
 Weight 
 O = 16 
 
 Molec- 
 ular 
 Weight 
 
 Specific 
 Gravity 
 Water=l 
 Air=l (A) 
 Hydrogen = 
 1(D) 
 
 Atomic 
 Vol. 
 At.Wt. 
 
 Specific 
 Heat 
 at C. 
 
 Sp. Gr. 
 
 1 
 
 Hydrogen, gas . 
 
 H 
 
 1.008 
 
 2.016 
 
 0.06949 A 
 
 
 3.410 
 
 2 
 
 liquid .... 
 
 H 
 
 1.008 
 
 2.016 
 
 0.700-252.60 
 
 1.4 
 
 6. 
 
 3 
 
 Indium .... 
 
 In 
 
 115 
 
 
 7.12?- 
 
 16.1 
 
 .05695 
 
 4 
 
 Iodine, gas . . . 
 
 I 
 
 126.97 
 
 
 8.72 A 
 
 
 .0336206 
 
 K 
 
 solid ..... 
 
 I 
 
 126.97 
 
 253.94 
 
 4.94817 
 
 25.7 
 
 .05412 
 
 6 
 
 Iridium, spongy . 
 
 Ir 
 
 193.0 
 
 
 15.86 
 
 12.2 
 
 
 7 
 
 crystalline . . 
 
 Ir 
 
 193.0 
 
 
 22.42 
 
 8.6 
 
 .0323 
 
 8 
 
 Iron, pure . . 
 
 Fe 
 
 55.9 
 
 
 7.85-7.88 
 
 7.1 
 
 .1162 
 
 a 
 
 wrought . . . 
 
 Fe 
 
 55.9 
 
 
 7.86 
 
 7.1 
 
 .1130 
 
 10 
 
 steel .... 
 
 Fe 
 
 55.9 
 
 
 7.60-7.80 
 
 7.3 
 
 .1066 
 
 11 
 
 gray pig . . . 
 
 Fe 
 
 55.9 
 
 
 7.03-7.13 
 
 7.9 
 
 
 12 
 
 white pig . . 
 
 Fe 
 
 55.9 
 
 
 7.58-7.73 
 
 7.3 
 
 .1050 
 
 13 
 
 Krypton, gas . . 
 
 Kr 
 
 81.8 
 
 81.8 
 
 ( 2.818 A 
 I 40.78 D 
 
 
 
 14 
 
 liquid .... 
 
 Kr 
 
 81.8 
 
 
 2.155-152 
 
 37.9 
 
 
 15 
 
 Lanthanum . . 
 
 La 
 
 138.9 
 
 
 6.1545 
 
 22.6 
 
 .04485 
 
 K; 
 
 Lead 
 
 Pb 
 
 206.9 
 
 
 11.34 
 
 18.2 
 
 .0310 
 
 17 
 
 Lithium. . . . 
 
 Li 
 
 7.03 
 
 
 0.5936 
 
 12 
 
 .9408 
 
 IS 
 
 Magnesium . . 
 
 Mg 
 
 24.36 
 
 
 1.69-1.75 
 
 14.3 
 
 .2456 
 
 1!) 
 
 Manganese . . 
 
 Mn 
 
 55.0 
 
 
 7.42 
 
 7.4 
 
 .1217 
 
 20 
 
 Mercury . . . 
 
 Hg 
 
 200.0 
 
 200.00 
 
 13.59532 
 
 14.7 
 
 .03346 
 
 21 
 
 Molybdenum . . 
 
 Mo 
 
 96.0 
 
 
 8.6-9.01 
 
 10.9 
 
 .0659 
 
 22 
 
 Neodymium . . 
 
 Nd 
 
 143.6 
 
 
 6.9563 
 
 20.6 
 
 
 i:\ 
 
 Neon 
 
 Ne 
 
 20 
 
 
 | 0.674 A 
 
 
 
 
 
 
 
 
 1 9.96 D 
 
 
 
 24 
 
 Nickel .... 
 
 Ni 
 
 58.7 
 
 
 8.6-8.93 
 
 6.7 
 
 .1084 
 
 25 
 
 Nitrogen, gas . . 
 
 N 
 
 14.04 
 
 28.08 
 
 0.96737 A 
 
 
 .2438 
 
 2<; 
 
 liquid .... 
 
 N 
 
 14.04 
 
 
 0.8042-195.50 
 
 17.5 
 
 
 27 
 
 Osmium . . . 
 
 Os 
 
 191 
 
 
 22.48 
 
 8.5 
 
 .03113 
 
 28 
 
 Oxygen, gas . . 
 
 
 
 16 
 
 32 
 
 1.10535 A 
 
 
 .2175 
 
 29 
 
 liquid .... 
 
 
 
 16 
 
 32 
 
 1.1181-182.5 
 
 14.3 
 
 
 30 
 
 Ozone .... 
 
 3 
 
 
 48 
 
 1.658 A 
 
 
 
 31 
 
 Palladium . . . 
 
 Pd 
 
 106.5 
 
 
 11.4-11.9 
 
 9.2 
 
 .0592 
 
 32 
 
 Phosphorus, yel. 
 
 P 
 
 31 
 
 124 
 
 1.823220 
 
 17.2 
 
 .202 
 
 33 
 
 red 
 
 P 
 
 31 
 
 124 
 
 2.11 
 
 14.7 
 
 .16981 
 
 34 
 
 liquid .... 
 
 P 
 
 31 
 
 
 1.76444.30 
 
 
 
 35 
 
 Platinum . . . 
 
 Pt 
 
 194.8 
 
 
 21. 481* 
 
 9.2 
 
 .0323 
 
 3<> 
 
 Potassium . . . 
 
 K 
 
 39.15 
 
 
 0.87513 
 
 44.7 
 
 .1662 
 
 37 
 
 Praseodymium . 
 
 Pr 
 
 140.5 
 
 
 6.4754 
 
 21.6 
 
 
 38 
 
 Radium .... 
 
 Ra 
 
 225 
 
 
 
 
 
 39 
 
 Rhodium . . . 
 
 Rh 
 
 103.0 
 
 
 12.1 
 
 8.5 
 
 .05803 
 
 40 
 
 Rubidium . . . 
 
 Rb 
 
 85.5 
 
 
 1.52215 
 
 56.3 
 
 
APPENDIX 
 
 255 
 
 | Number II 
 
 11* 
 
 Effi~ 
 
 41-x 
 
 Electrical 
 Conduc- 
 tivity 
 at 0"C. ' 
 
 Thermal 
 Conduc- 
 tivity 
 Kt at C. 
 Ag = 1.00 
 
 Linear 
 Coefficient of 
 Expansion 
 
 Melting 
 Point, 
 C. 
 
 Boiling 
 Point, 
 C. 
 
 1 
 
 3.44 
 
 
 .0 3 3270 
 
 
 AtC. 
 
 256.5 
 
 - 252.5 
 
 2 
 
 6.05 
 
 
 
 
 
 
 
 o 
 
 6.56 
 
 119500 
 
 
 .0 4 417 
 
 40 
 
 115 
 
 red heat 
 
 4 
 
 4.27 
 
 
 
 
 
 
 
 5 
 
 6.86 
 
 
 
 .0 4 837 
 
 -190-17 
 
 114.2 
 
 184.35 
 
 6 
 
 
 
 
 
 
 
 
 7 
 
 6.23 
 
 
 
 .0 4 0700 
 
 40 
 
 1950 
 
 
 8 
 
 6.50 
 
 131000 
 
 .1665 
 
 .0 4 1182 
 
 0-100 
 
 1804 
 
 
 9 
 
 6.32 
 
 
 .2070 
 
 .0 4 11 
 
 0-100 
 
 1600 
 
 
 10 
 
 5.96 
 
 63000 
 
 .1300 
 
 .0 4 11 
 
 0-100 
 
 1375 
 
 
 11 
 
 
 { 10200- 
 
 
 .0 4 1061 
 
 40 
 
 1275 
 
 
 1L> 
 
 5.87 
 
 (11300 
 
 .1490 
 
 
 
 1075 
 
 
 13 
 
 
 
 
 
 
 169 
 
 151.7 
 
 14 
 
 
 
 
 
 
 
 
 15 
 
 6.23 
 
 
 
 
 
 810 
 
 
 1(5 
 
 3.52 
 
 504CO 
 
 .0836 
 
 .0 4 2924 
 
 40 
 
 327 
 
 1400-1600 
 
 17 
 
 6.62 
 
 119000 
 
 
 
 
 186 
 
 >1400 
 
 IS 
 
 5.98 
 
 230000 
 
 .3760 
 
 .0 4 2694 
 
 40 
 
 632.6 
 
 1100 
 
 19 
 
 6.70 
 
 
 
 
 
 1245 
 
 
 20 
 
 6.69 
 
 10630 
 
 .0148 
 
 .0 3 182 
 
 0-100 
 
 38.85 
 
 357.33 
 
 21 
 
 6.33 
 
 
 
 
 
 
 
 22 
 
 
 
 
 
 
 840 
 
 
 23 
 
 
 
 
 
 
 
 f 243 to 
 
 
 
 
 
 
 
 
 1 - 233 
 
 24 
 
 6.36 
 
 144200 i 
 
 .1420 
 
 .0 4 1279 
 
 40 
 
 1484 
 
 
 25 
 
 3.42 
 
 
 .0 4 524 
 
 
 
 210.5 (84 
 
 - 195.5 
 
 2<; 
 
 
 
 
 
 
 [mm.) 
 
 
 27 
 
 5.95 
 
 105300 
 
 
 .0 4 0657 
 
 40 
 
 2500 
 
 
 28 
 
 3.48 
 
 
 .0 4 563 
 
 
 
 < 230 
 
 182.5 
 
 29 
 
 
 
 
 
 
 
 
 30 
 
 
 
 
 
 
 decomp. 270 
 
 -119 
 
 31 
 
 6.30 
 
 97900 
 
 .1683 
 
 .0 4 1176 
 
 40 
 
 1535-1586 
 
 
 32 
 
 6.26 
 
 
 
 .0 3 124 
 
 0-44 
 
 44.2 
 
 290 
 
 33 
 
 5.26 
 
 
 
 
 
 350 (yel.) 
 
 
 34 
 
 
 
 
 
 
 
 
 35 
 
 6.29 
 
 91200 
 
 .1664 
 
 .0 4 0899 
 
 40 
 
 1710-1780 
 
 
 36 
 
 6.51 
 
 150500 
 
 
 .0 4 83 
 
 0-50 
 
 62.5 
 
 757.5 
 
 37 
 
 
 
 
 
 
 940 
 
 
 38 
 
 
 
 
 
 
 
 
 39 
 
 5.97 
 
 
 
 .0 4 0850 
 
 40 
 
 1650-2000 
 
 
 40 
 
 
 
 
 
 
 38.5 
 
 696 
 
 f See note on p. 252. 
 
256 
 
 APPENDIX 
 
 | Nnmber 1 1 
 
 Name 
 
 Sym- 
 bol 
 
 Atomic 
 Weight 
 16 
 
 Molec- 
 ular 
 
 Weight 
 
 Specific 
 Gravity- 
 Water = 1 
 Air = l (A) 
 Hydrogen = 
 
 Atomic 
 Vol. 
 At.Wt. 
 
 Specific 
 Heat 
 at C. 
 
 
 Sp. Qr. 
 
 1 
 
 Ruthenium, spon. 
 
 Ru 
 
 101.7 
 
 
 8.6 
 
 11.8 
 
 
 2 
 
 melted . . . 
 
 Ru 
 
 101.7 
 
 
 11.4 
 
 8.9 
 
 
 3 
 
 cryst 
 
 Ru 
 
 101.7 
 
 
 12.268 
 
 8.3 
 
 .0611 
 
 4 
 
 Samarium . . . 
 
 Sm 
 
 150.3 
 
 
 7.7-7.8 
 
 19.4 
 
 
 5 
 
 Scandium . . . 
 
 Sc 
 
 44.1 
 
 
 
 
 
 6 
 
 Selenium, amorph. 
 
 Se 
 
 79.2 
 
 633.6 
 
 4.26-4.2825 
 
 18.5 
 
 .09533 
 
 7 
 
 monoclinic . . 
 
 Se 
 
 79.2 
 
 633.6 
 
 4.4725 
 
 17.7 
 
 .08401 
 
 8 
 
 hexagonal . . 
 
 Se 
 
 79.2 
 
 633.6 
 
 4.825 
 
 16.5 
 
 
 ( .) 
 
 Silicon, amorph. 
 
 Si 
 
 28.4 
 
 
 2.00 
 
 14.2 
 
 
 10 
 
 cryst 
 
 Si 
 
 28.4 
 
 
 2.49i 
 
 11.4 
 
 .169722 
 
 11 
 
 Silver . . . . 
 
 Ag 
 
 107.93 
 
 
 10.53 
 
 10.2 
 
 .0559 
 
 12 
 
 Sodium .... 
 
 Na 
 
 23.05 
 
 
 0.973513.50 
 
 23.7 
 
 .2934 
 
 13 
 
 Strontium . . . 
 
 Sr 
 
 87.6 
 
 
 2.54 
 
 34.5 
 
 
 
 Sulphur, 
 
 
 
 
 
 
 
 14 
 
 amorphous soft 
 
 S 
 
 32.06 
 
 256.48 
 
 1.9556 
 
 16.4 
 
 
 15 
 
 " yellow 
 
 S 
 
 32.06 
 
 256.48 
 
 2.046 
 
 15.6 
 
 
 16 
 
 rhombic . . . 
 
 Sa 
 
 32.06 
 
 256.48 
 
 2.05-2.07 
 
 15.6 
 
 .163 
 
 17 
 
 monoclinic . . 
 
 S/3 
 
 32.06 
 
 256.48 
 
 1.958 
 
 16.4 
 
 
 18 
 
 plastic . . . 
 
 Sy 
 
 32.06 
 
 256.48 
 
 1.92 
 
 16.7 
 
 
 11) 
 
 Tantalum . . . 
 
 Ta 
 
 183 
 
 
 12.79 
 
 143 
 
 
 20 
 
 Tellurium, amorp. 
 
 Te 
 
 127.6 
 
 255.2 
 
 6.0152 
 
 21.2 
 
 
 21 
 
 cryst 
 
 Te 
 
 127.6 
 
 255.2 
 
 6.27 
 
 20.4 
 
 .0475 
 
 22 
 
 Terbium . . . 
 
 Tb 
 
 160 
 
 
 
 
 
 23 
 
 Thallium . . . 
 
 Tl 
 
 204.1 
 
 
 11.85 
 
 17.2 
 
 .0326 
 
 24 
 
 Thorium, amorph. 
 
 Th 
 
 232.5 
 
 
 11.0011 
 
 21.1 
 
 
 2f> 
 
 cryst 
 
 Th 
 
 232.5 
 
 
 11.23 
 
 20.7 
 
 
 20 
 
 Thulium .... 
 
 Tm 
 
 171 
 
 
 
 
 
 27 
 
 Tin, gray . . . 
 
 Sn 
 
 119.0 
 
 
 5.846615 
 
 20.3 
 
 .0545 
 
 28 
 
 rhombic . . . 
 
 Sn 
 
 119.0 
 
 
 6.53-6.56 
 
 18.2 
 
 .0559 
 
 2!) 
 
 tetragonal . . 
 
 Sn 
 
 119.0 
 
 
 7.298415 
 
 16.3 
 
 .0559 
 
 30 
 
 Titanium . . . 
 
 Ti 
 
 48.1 
 
 
 3.543 
 
 13.6 
 
 .1125 
 
 31 
 
 Tungsten . . . 
 
 W 
 
 184 
 
 
 18.77 
 
 9.8 
 
 .0336 
 
 32 
 
 Uranium . . . 
 
 u 
 
 238.5 
 
 
 18.685V 30 
 
 12.8 
 
 .0280 
 
 33 
 
 Vanadium . . . 
 
 V 
 
 51.2 
 
 
 5.8715 
 
 8.7 
 
 .1153 
 
 34 
 
 Xenon, gas . . 
 
 Xe 
 
 128 
 
 
 | 4.422 A 
 1 63.5 D 
 
 
 
 35 
 
 liquid. . . . 
 
 Xe 
 
 128 
 
 
 3.52-109.10 
 
 49.1 
 
 
 36 
 
 Ytterbium . . . 
 
 Yb 
 
 173.0 
 
 
 
 
 
 37 
 
 Yttrium . . . 
 
 Yt 
 
 89.0 
 
 
 3.8015 
 
 23.4 
 
 
 38 
 
 Zinc 
 
 Zn 
 
 65.4 
 
 
 7.14216 
 
 9.2 
 
 .09356 
 
 3!) 
 
 Zirconium, amorp. 
 
 Zr 
 
 90.6 
 
 
 4.15 
 
 21.8 
 
 
 40 
 
 cryst 
 
 Zr 
 
 90.6 
 
 
 5.3 
 
 17.1 
 
 .0660 
 
APPENDIX 
 
 257 
 
 i Number 1 1 
 
 *j* - 
 
 Electrical 
 Conduc- 
 tivity 
 at Wt. 
 
 Thermal 
 Conduc- 
 tivity 
 Kt at C. 
 Ag = 1.00 
 
 Linear 
 Coefficient of 
 Expansion 
 
 Melting 
 Point, 
 
 foiling 
 Point, 
 
 1 
 
 
 
 
 
 At C. 
 
 > 1950 
 
 
 2 
 
 
 
 
 
 
 2000 
 
 
 3 
 
 6.21 
 
 
 
 .0 4 0963 
 
 40 
 
 2000 
 
 
 4 
 
 
 
 
 
 
 
 
 5 
 
 
 
 
 
 
 
 
 6 
 
 7.55 
 
 
 
 
 
 50 
 
 690 
 
 7 
 
 6.65 
 
 
 
 .0 4 3680 
 
 40 
 
 170-18 
 
 690 
 
 8 
 
 
 
 
 
 
 217 
 
 690 
 
 g 
 
 
 
 
 
 
 
 3500 
 
 10 
 
 4.82 
 
 200-15600 
 
 
 .0 4 0763 
 
 40 
 
 1200 
 
 3500 
 
 11 
 
 6.04 
 
 681200 
 
 1.000 
 
 .0 4 1921 
 
 40 
 
 961.5 
 
 2050 
 
 12 
 
 6.76 
 
 211000 
 
 .365 
 
 .0 4 72 
 
 0-50 
 
 97.6 
 
 877.5 
 
 1.3 
 
 
 40300 
 
 
 
 
 900 
 
 
 14 
 
 
 
 
 
 
 >120 
 
 444.6 
 
 15 
 
 
 
 
 
 
 
 444.6 
 
 1(5 
 
 5.23 
 
 
 
 .0 4 6413 
 
 40 
 
 114.5 
 
 444.6 
 
 17 
 
 
 
 
 
 
 119.25 
 
 444.6 
 
 18 
 
 
 
 
 
 
 
 444.6 
 
 19 
 
 
 60600 
 
 
 .0 4 08 
 
 
 2250 
 
 
 20 
 
 
 
 
 .0 4 1675 
 
 40 
 
 446 
 
 1390 
 
 21 
 
 6.07 
 
 46600 
 
 
 .0 4 3440 
 
 0-20 
 
 452 
 
 1390 
 
 22 
 
 
 
 
 
 
 
 
 23 
 
 6.65 
 
 56800 
 
 
 .0 4 3021 
 
 40 
 
 301.7 
 
 1600-1800 
 
 24 
 
 
 
 
 
 
 
 
 25 
 
 
 
 
 
 
 
 
 27 
 
 6.49 
 
 
 
 
 
 stable <20 
 
 
 28 
 
 6.65 
 
 
 
 
 
 stable >170 
 
 
 29 
 
 6.65 
 
 76600 
 
 .1528 
 
 .0 4 2234 
 
 40 
 
 232 
 
 1450-1600 
 
 30 
 
 5.41 
 
 
 
 
 
 3000 
 
 
 31 
 
 6.18 
 
 
 
 
 
 1700 
 
 
 32 
 
 6.68 
 
 
 
 
 
 800 
 
 
 33 
 
 5.90 
 
 
 
 
 
 1680 
 
 
 34 
 
 
 
 
 
 
 -140 3 
 
 - 109.1 
 
 35 
 
 
 
 
 
 
 
 
 37 
 
 
 
 
 
 
 
 
 38 
 
 6.12 
 
 186000 
 
 .2653 
 
 .0 4 2918 
 
 40 
 
 419 
 
 918 
 
 39 
 
 
 
 
 
 
 1500 
 
 
 40 
 
 5.98 
 
 
 
 
 
 
 
 t See note on p. 252. 
 
258 
 
 APPENDIX 
 
 VI. VOLUME AND WEIGHT OF WATER FROM C. TO 31 C.* 
 
 Tempera- 
 ture 
 
 Volume of one 
 gram in c.c. 
 
 , Weight of one 
 c.c. in grams 
 
 Tempera- 
 ture 
 
 Volume of one 
 gram in c.c. 
 
 Weight of one 
 c.c. in grams 
 
 
 
 1.000126 
 
 0.999874 
 
 16 
 
 1.001025 
 
 0.998976 
 
 1 
 
 1.000070 
 
 0.999930 
 
 17 
 
 1.001193 
 
 0.998808 
 
 2 
 
 1.000030 
 
 0.999970 
 
 18 
 
 1.001373 
 
 0.998629 
 
 3 
 
 1.000007 
 
 0.999993 
 
 19 
 
 1.001564 
 
 0.998438 
 
 4 
 
 ' 1.000000 
 
 1.000000 
 
 20 
 
 1.001768 
 
 0.998235 
 
 5 
 
 1.000008 
 
 0.999992 
 
 21 
 
 1.001981 
 
 0.998023 
 
 6 
 
 1.000031 
 
 0.999969 
 
 22 
 
 1.002204 
 
 0.997801 
 
 7 
 
 1.000069 
 
 0.999931 
 
 23 
 
 1.002438 
 
 0.997568 
 
 8 
 
 1.000122 
 
 0.999878 
 
 24 
 
 1.006781 
 
 0.997326 
 
 9 
 
 1.000188 
 
 0.999812 
 
 25 
 
 1.002935 
 
 0.997073 
 
 10 
 
 1.000269 
 
 0.999731 
 
 26 
 
 1.003199 
 
 0.996811 
 
 11 
 
 1.000363 
 
 0.999637 
 
 27 
 
 1.003472 
 
 0.996540 
 
 12 
 
 1.000470 
 
 0.999530 
 
 28 
 
 1 003788 
 
 0.996226 
 
 13 
 
 1.000590 
 
 0.999410 
 
 29 
 
 1.004045 
 
 0.995971 
 
 14 
 
 1.000722 
 
 0.999278 
 
 30 
 
 1.004346 
 
 0.995673 
 
 15 
 
 1.000867 
 
 0.999134 
 
 31 
 
 1.004656 
 
 0.995365 
 
 For the most recent results on the expansion of water, 
 which do not differ materially from the preceding, see An- 
 nalen d. Physik u. Chemie, [K R], 60, 340 (1897). 
 * Wied. Ann., 47, 400 (1892). 
 
APPENDIX 
 
 259 
 
 VII. VAPOR PRESSURE OF WATER FROM C. TO 100 C. 
 IN MILLIMETERS OF MERCURY.* 
 
 Temp. 
 
 Pressure 
 
 Temp. 
 
 Pressure 
 
 Temp. 
 
 Pressure 
 
 Temp. 
 
 Pressure 
 
 
 
 4.569 
 
 25 
 
 23.517 
 
 50 
 
 91.98 
 
 75 
 
 288.76 
 
 1 
 
 4.909 
 
 26 
 
 24.956 
 
 51 
 
 96.66 
 
 76 
 
 301.09 
 
 2 
 
 5.272 
 
 27 
 
 26.471 
 
 52 
 
 101.55 
 
 77 
 
 313.85 
 
 3 
 
 5.658 
 
 28 
 
 28.065 
 
 53 
 
 106.65 
 
 78 
 
 327.05 
 
 4 
 
 6.069 
 
 29 
 
 29.744 
 
 54 
 
 111.97 
 
 79 
 
 340.73 
 
 5 
 
 6.507 
 
 30 
 
 31.51 
 
 55 
 
 117.52 
 
 80 
 
 354.87 
 
 6 
 
 6.972 
 
 31 
 
 33.37 
 
 56 
 
 123.29 
 
 81 
 
 369.51 
 
 7 
 
 7.466 
 
 32 
 
 35.32 
 
 57 
 
 129.31 
 
 82 
 
 384.64 
 
 8 
 
 7.991 
 
 33 
 
 37.37 
 
 58 
 
 135.58 
 
 83 
 
 400.29 
 
 9 
 
 8.548 
 
 34 
 
 39.52 
 
 59 
 
 142.10 
 
 84 
 
 416.47 
 
 10 
 
 9.140 
 
 35 
 
 41.78 
 
 60 
 
 148.88 
 
 85 
 
 433.19 
 
 11 
 
 9.767 
 
 36 
 
 44.16 
 
 61 
 
 155.95 
 
 86 
 
 450.47 
 
 12 
 
 10.432 
 
 37 
 
 46.65 
 
 62 
 
 163.29 
 
 87 
 
 468.32 
 
 13 
 
 11.137 
 
 38 
 
 49.26 
 
 63 
 
 170.02 
 
 88 
 
 486.76 
 
 14 
 
 11.884 
 
 39 
 
 52.00 
 
 64 
 
 178.86 
 
 89 
 
 505.81 
 
 15 
 
 12.674 
 
 40 
 
 54.87 
 
 65 
 
 187.10 
 
 90 
 
 525.47 
 
 16 
 
 13.510 
 
 41 
 
 57.87 
 
 66 
 
 195.67 
 
 91 
 
 545.77 
 
 17 
 
 14.395 
 
 42 
 
 61.02 
 
 67 
 
 204.56 
 
 92 
 
 566.71 
 
 18 
 
 15.330 
 
 43 
 
 64.31 
 
 68 
 
 213.79 
 
 93 
 
 588.83 
 
 19 
 
 16.319 
 
 44 
 
 67.76 
 
 69 
 
 223.37 
 
 94 
 
 610.64 
 
 20 
 
 17.363 
 
 45 
 
 71.36 
 
 70 
 
 233.31 
 
 95 
 
 633.66 
 
 21 
 
 18.466 
 
 46 
 
 75.13 
 
 71 
 
 243.62 
 
 96 
 
 657.40 
 
 22 
 
 19.630 
 
 47 
 
 79.07 
 
 72 
 
 254.30 
 
 97 
 
 681.88 
 
 23 
 
 20.858 
 
 48 
 
 83.19 
 
 73 
 
 265.38 
 
 98 
 
 707.13 
 
 24 
 
 22.152 
 
 49 
 
 87.49 
 
 74 
 
 276.87 
 
 99 
 
 733.16 
 
 * Taken from Ostwald's Manual of Physico-Chemical Measurements. 
 
260 
 
 APPENDIX 
 
 VIII. TABLE OF ELECTRO-CHEMICAL EQUIVALENTS 
 
 Table of Electro-chemical Equivalents based on the definition of the 
 ampere and the atomic weights, oxygen being 16 
 
 Element 
 
 Atomic Weight 
 
 Valency 
 
 Chemical 
 Equivalent 
 
 Electro-chemical 
 Equivalent 
 Grams pef 
 coulomb 
 
 Coulombs 
 per gram 
 
 (J rains per 
 ampere-hour 
 
 Ampere-hours 
 per pound 
 
 Electropositive 
 
 
 
 
 
 
 
 
 Aluniinum .... 
 
 27.11 
 
 3. 
 
 9.037 
 
 .00009362 
 
 10680. 
 
 .3370 
 
 1346. 
 
 Antimony .... 
 
 120.43 
 
 3. 
 
 40.14 
 
 .0004159 
 
 2405. 
 
 1.497 
 
 303.0 
 
 Bismuth 
 
 208.11 
 
 3. 
 
 69.37 
 
 .0007186 
 
 1392. 
 
 2.587 
 
 175.3 
 
 Cadmium .... 
 
 112.38 
 
 2. 
 
 56.19 
 
 .0005821 
 
 1718. 
 
 2.096 
 
 216.4 
 
 Cobalt 
 
 58.99 
 
 2. 
 
 29.5 
 
 .0003056 
 
 3272. 
 
 1.100 
 
 412.2 
 
 Copper (cuprous) 
 
 63.6 
 
 1. 
 
 63.6 
 
 .0006589 
 
 1518. 
 
 2.372 
 
 191.2 
 
 Copper (cupric) . . 
 
 63.6 
 
 2. 
 
 31.8 
 
 .0003295 
 
 3036. 
 
 1.186 
 
 382.4 
 
 Gold 
 
 197.23 
 
 3. 
 
 65.78 
 
 .0006815 
 
 1467. 
 
 2.453 
 
 184.7 
 
 Hydrogen .... 
 
 1.008 
 
 1. 
 
 1.008 
 
 .00001044 
 
 95785. 
 
 .03758 
 
 12070. 
 
 Iron (ferrous) . . . 
 
 56.02 
 
 2. 
 
 28.01 
 
 .0002902 
 
 3446. 
 
 1.045 
 
 434.0 
 
 Iron (ferric) . . . 
 
 56.02 
 
 3. 
 
 18.67 
 
 .0001934 
 
 5171. 
 
 .6962 
 
 651.5 
 
 Lead 
 
 20fi Q9 
 
 2. 
 
 103.5 
 
 .001072 
 
 932.8 
 
 3.859 
 
 117.5 
 
 Magnesium .... 
 
 ^UO.r/^ 
 
 24.28 
 
 2. 
 
 12.14 
 
 .0001258 
 
 7949. 
 
 .4528 
 
 1001. 
 
 Manganese .... 
 
 54.99 
 
 2. 
 
 27.50 
 
 .0002849 
 
 3510. 
 
 1.026 
 
 442.1 
 
 Mercury (mercurous) 
 
 200. 
 
 1. 
 
 200. 
 
 .002072 
 
 482.6 
 
 7.459 
 
 60.81 
 
 Mercury (mercuric) . 
 
 200. 
 
 2. 
 
 100. 
 
 .001036 
 
 965.3 
 
 3.730 
 
 121.6 
 
 Nickel 
 
 58.69 
 
 2. 
 
 29.35 
 
 .0003041 
 
 3288. 
 
 1.095 
 
 414.2 
 
 Platinum .... 
 
 194.89 
 
 4. 
 
 48.72 
 
 .0005047 
 
 1981. 
 
 1.817 
 
 249.6 
 
 Potassium .... 
 
 39.11 
 
 1. 
 
 39.11 
 
 .0004052 
 
 2468. 
 
 1.459 
 
 310.9 
 
 Silver 
 
 107 <> 
 
 1 
 
 107.92 
 
 .001118 
 
 894.5 
 
 4.025 
 
 112.7 
 
 Sodium 
 
 i\j ^ *? 
 23.05 
 
 1. 
 
 23.05 
 
 .0002388 
 
 4188. 
 
 .8597 
 
 527.6 
 
 Tin (stannous) . . 
 
 119.05 
 
 2. 
 
 59.52 
 
 .0006166 
 
 1622. 
 
 2.220 
 
 204.3 
 
 Tin (stannic) . . . 
 
 119.05 
 
 4. 
 
 29.76 
 
 .0003083 
 
 3243. 
 
 1.110 
 
 408.6 
 
 Zinc 
 
 65.41 
 
 2. 
 
 32.70 
 
 AAAOOOO 
 
 2952. 
 
 1.220 
 
 371.8 
 
 Electronegative 
 
 
 
 
 . UUUOOOo 
 
 
 
 
 Bromine 
 
 79.95 
 
 j 
 
 79.95 
 
 AAAQOQQ 
 
 1207. 
 
 2.982 
 
 152.1 
 
 Chlorine 
 
 35.45 
 
 1. 
 
 35.45 
 
 vUUojJoO 
 
 .0003673 
 
 2723. 
 
 1.322 
 
 343.1 
 
 Iodine 
 
 126.85 
 
 1, 
 
 126.85 
 
 .001314 
 
 761.0 
 
 4.730 
 
 95.90 
 
 Nitrogen . 
 
 14.04 
 
 3. 
 
 4.68 
 
 .00004848 
 
 20627. 
 
 .1745 
 
 2599. 
 
 
 16. 
 
 2. 
 
 S. 
 
 .00008288 
 
 12066. 
 
 .2984 
 
 1520. 
 
 
 
 
 
 
 
 
 
APPENDIX 
 
 261 
 
 IX. TABLE SHOWING THE RELATIONS BETWEEN UNITS 
 OF ELECTRICITY, HEAT, AND POWER 
 
 1 ampere = 1 volt -r- 1 ohm. 
 
 " =1 coulomb per second. 
 
 1 ampere hour = 1 coulomb per sec- 
 ond kept up for 
 one hour. 
 
 1 ampere hour = 3600 coulombs. 
 1 volt = 1 ampere X 1 ohm. 
 1 ohm = 1 volt -4- 1 ampere. 
 
 1 joule = 1 volt x 1 coulomb. 
 " = .2381 calorie. 
 
 = .73732 foot-pound. 
 " = .10194 kilogram-meter. 
 
 1 calorie = 4.2 joules. 
 
 = 3.0968 foot-pounds. 
 " = .42815 kilogram-meter. 
 
 1 foot-pound = 1.3563 joules. 
 = .32292 calorie. 
 = .13825 kilogram- 
 meter. 
 
 1 kilogram-meter = 9.81 joules. 
 
 " =2.3362 calories. 
 
 = 7.233 foot- 
 pounds. 
 
 1 watt-hour = 1 watt kept up for 
 one hour. 
 
 1 watt-hour 1 joule per second 
 kept up for one 
 hour. 
 
 1 watt-hour = 3600 joules. 
 
 = 857.16 calories. 
 = 2654.4 foot-pounds. 
 = 366.98 kilogram-me- 
 ters. 
 
 1 watt = 1 joule per second. 
 " = .2381 calorie per second. 
 = .73732 foot-pound per sec- 
 ond. 
 
 1 watt = .10194 kilogram-meter per 
 second. 
 
 1 watt = .0013406 horse-power. 
 " = .001 kilowatt. 
 
 1 horse-power = 745.94 watts. 
 
 = 177.6 calories per 
 second. 
 
 1 horse-power* = 10656 calories per 
 minute. 
 
 1 horse-power = 550 foot-pounds per 
 second. 
 
 1 horse-power = 33000 foot-pounds 
 per minute. 
 
 1 horse-power = 76.04 kilogram, 
 meters per sec- 
 ond. 
 
 1 horse-power = 4562.4 kilogram- 
 meters per min- 
 ute. 
 
 1 horse-power = .74594 kilowatt. 
 
 1 kilowatt = 1000 watts. 
 
 " = 1000 joules per second. 
 ". = 238.1 calories per sec- 
 ond. 
 
 1 kilowatt = 14286 calories 
 minute. 
 
 per 
 
 1 kilowatt = 737.32 foot-pounds per 
 second. 
 
 1 kilowatt = 44239 foot-pounds per 
 minute. 
 
 1 kilowatt = 101.94 kilogram-me- 
 ters per second. 
 
 1 kilowatt --= 6116.4 kilogram-me- 
 ters per minute. 
 
 1 kilowatt = 1.3406 horse-power. 
 
262 
 
 APPENDIX 
 
 X. HEATS OF COMBINATION 
 
 Heats of Combination in Calories, for Equivalent Weights in Grams, 
 of Chlorides, Bromides, Iodides, Sulphate, and Nitrates * 
 
 Element 
 
 Valence 
 
 Chloride 
 
 Bromide 
 
 Iodide 
 
 Sulphate 
 
 Nitrate 
 
 Aluminium . . 
 
 3 
 
 53660 
 
 39900 
 
 23463 
 
 25315 
 
 
 Antimony . . . 
 
 3 
 
 30463 
 
 
 
 
 
 Bismuth 
 
 3 
 
 30210 
 
 
 
 
 
 Cadmium . 
 
 2 
 
 46620 
 
 37600 
 
 24215 
 
 44940 
 
 43000 
 
 Cobalt .... 
 
 2 
 
 38240 
 
 
 
 44350 
 
 42270 
 
 Copper .... 
 
 1 
 
 32875 
 
 24985 
 
 16260 
 
 
 
 Copper .... 
 
 2 
 
 
 
 
 27980 
 
 26205 
 
 Gold .... 
 
 3 
 
 7607 
 
 2950 
 
 
 
 
 Hydrogen . . . 
 
 1 
 
 39315 
 
 28380 
 
 13170 
 
 39170 
 
 33830 
 
 Iron 
 
 2 
 
 41025 
 
 
 
 46600 
 
 44835 
 
 Lead .... 
 
 2 
 
 41385 
 
 32225 
 
 19900 
 
 
 34035 
 
 Magnesium . . 
 
 2 
 
 75505 
 
 
 
 90090 
 
 88240 
 
 Manganese . . 
 
 2 
 
 55995 
 
 
 
 60625 
 
 58860 
 
 Mercury . . . 
 
 2 
 
 31580 
 
 17155 
 
 
 
 18535 
 
 Nickel .... 
 
 2 
 
 37265 
 
 
 
 43475 
 
 41710 
 
 Silver .... 
 
 1 
 
 29380 
 
 22700 
 
 13800 
 
 10195 
 
 8390 
 
 Tin .... 
 
 2 
 
 40395 
 
 
 
 
 
 Zinc 
 
 2 
 
 48605 
 
 37965 
 
 24615 
 
 53045 
 
 51255 
 
 * These values are taken from Thomsen's Thermo-chemische Unter- 
 suchungen. The sulphates, nitrates, and hydrogen compounds are for 
 aqueous solutions. The chorides, bromides, and iodides are anhydrous. 
 
APPENDIX 263 
 
 XL SPECIFIC RESISTANCE OF VARIOUS SUBSTANCES 
 
 Substance 
 
 Temperature 
 
 j*> 
 
 J 
 
 1 
 
 GO 
 
 p 
 in Ohms 
 
 % Solution 
 
 Observer 
 
 
 0C. 
 
 10 6 
 
 .000001500 
 
 
 Matthiesen 
 
 
 
 10.6 
 
 .000001530 
 
 
 
 
 M 
 
 89 
 
 .000001594 
 
 
 i 
 
 Copper (hard drawn) .... 
 Gold (annealed) 
 Gold (hard drawn) 
 Aluminium (annealed) . . . 
 Platinum (annealed) .... 
 
 II 
 
 8.9 
 19.3 
 19.3 
 2.6 
 21.2 
 8.1 
 
 .000001629 
 .000002052 
 .000002089 
 .000002903 
 .000009030 
 .000009687 
 
 
 ' 
 
 Tin (pressed) . . 
 
 II 
 
 7 3 
 
 00001317 
 
 
 t 
 
 Zinc (pressed) . . 
 
 
 
 71 
 
 .000005598 
 
 
 4 
 
 Lead (pressed) 
 
 II 
 
 11.4 
 
 .00001957 
 
 
 4 
 
 Nickel (pressed) 
 
 M 
 
 8.5 
 
 00001242 
 
 
 j 
 
 German silver . . 
 
 II 
 
 
 about .0000209 
 
 
 4 
 
 Graphite . . . 
 
 (( 
 
 2 3 
 
 0024 to .042 
 
 
 Everett 
 
 Retort carbon 
 
 II 
 
 1 9 
 
 07 
 
 
 
 Mercury 
 
 M 
 
 13 6 
 
 000094073* 
 
 
 
 Nitric acid in water 
 
 18 C. 
 
 1.185 
 
 1.28 t 
 
 29.7 
 
 Kohlrausch 
 
 Hydrochloric acid in water . . 
 Sulphuric acid in water . . . 
 Phosphoric acid in water . . . 
 Tartaric acid in water .... 
 Acetic acid in water .... 
 Ammonium chloride in water . 
 Sodium chloride in water . . 
 Sodium sulphate in water . . 
 Zinc sulphate in water . . . 
 Zinc sulphate in water . . . 
 Copper sulphate in water . . . 
 Potassium sulphate in water 
 Potassium bichromate in water- 
 
 n' 
 
 10 C. 
 
 1.092 
 1.224 
 1.307 
 1.107 
 1.022 
 
 1.270 
 1.422 
 1.205 
 
 1.31 f 
 1.36 t 
 4.79 t 
 9.97 t 
 61.9 t 
 2.5 t 
 4.7 t 
 11.3 t 
 28.5 t 
 33.7 J 
 29.3 $ 
 16.6 $ 
 29,6 J 
 
 18.3 
 80.4 
 46.8 
 22.4 
 16.6 
 
 Kohlrausch 
 and 
 ) Nippoldt 
 
 Ewing 
 and 
 Macgregor. 
 
 Further data on the conductivity of the solutions can be found in 
 Physikalisch-Chemische Tabellen, Landolt and Bornstein, pp. 103, 
 106. 
 
 Kohlrausch and Nippoldt, Pogg. Ann., 138, p. 379 (1869). 
 
 Grotrian Pogg. Ann., 151, p. 378 (1874). 
 
 Kohlrausch and Grotrian, Pogg. Ann., 159, p. 233 (1876); and 
 Wied. Ann., 6, p. 145 (1879). 
 
 * From the definition of the ohm. 
 t Solution of minimum resistance. J Saturated solution. 
 
264 
 
 APPENDIX 
 
 XII. DENSITIES OF VARIOUS SUBSTANCES 
 
 The following table gives the weight in grams of 1 cc. of 
 the substance. These densities are but approximate. 
 
 Acetic acid 1.064 
 
 Agate 2.615 
 
 Alcohol, absolute . . . 0.796 
 Alcohol, methyl . . . .0.796 
 
 Alum 1.724 
 
 Aluminium 2.670 
 
 Amber 1.078 
 
 Antimony, cast .... 6.720 
 Apple-tree wood .... 0.790 
 
 Arsenic ' . . 8.310 
 
 Ash, dry 0.690 
 
 Ash, green 0.760 
 
 Asphalt 2.500 
 
 Basalt 2.950 
 
 Beech, dry ... 0.690 to 0.800 
 
 Beeswax 0.964 
 
 Bell-metal 8.050 
 
 Benzine .... 0.72 to 0.740 
 
 Benzole 0.884 
 
 Birch 0.690 
 
 Bismuth, cast 9.822 
 
 Blood 1.060 
 
 Boxwood 1.280 
 
 Brass, cast 8.400 
 
 Brass, sheet 8.440 
 
 Brick 1.6 to 2.000 
 
 Bromine 3.187 
 
 Butter 0.942 
 
 Calcium chloride . . .. 2.230 
 
 Camphor 0.988 
 
 Carbon disulphide . . . 1.272 
 Carbon dioxide, liquid . . 0.947 
 Cedar, American .... 0.554 
 
 Chalk 1.8 to 2.800 
 
 Cherry-tree 0.710 
 
 Chestnut 0.606 
 
 Chloroform. . 1.500 
 
 Clay 1.920 
 
 Coal, anthracite . 1.26 to 1.800 
 Coal, bituminous . 1.27 to 1.423 
 
 Cobalt 8.800 
 
 Concrete, ordinary . . . 1.900 
 Concrete, in cement . . . 2.200 
 
 Cork 0.240 
 
 Copper, cast 8.830 
 
 Copper, sheet 8.878 
 
 Deal, Norway 0.689 
 
 Diamond 3.530 
 
 Earth .... 1.52 to 2.000 
 
 Ebony 1.187 
 
 Elder 0.690 
 
 Elm 0.579 
 
 Elm, Canadian .... 0.725 
 
 Emerald 2.770 
 
 Emery 3.900 
 
 Ether 0.720 
 
 Feldspar 2.600 
 
 Fir, spruce 0.512 
 
 Fluorspar 3.200 
 
 Galena 7.580 
 
 German silver 8.432 
 
 Glass, flint . . . . 3.0 to 3.600 
 
 Glass, crown 2.520 
 
 Glass, plate 2.760 
 
 Glycerine 1.260 
 
 Gold 19.360 
 
 Gypsum, crys 2.310 
 
 Granite 2.650 
 
 Graphite 2.500 
 
 Gun-metal 8.561 
 
 Gutta-percha 0.966 
 
 Heavy-spar 4.430 
 
 Honey ....... 1.450 
 
 Human body 0.890 
 
APPENDIX 
 
 265 
 
 XII. DENSITIES OF VARIOUS SUBSTANCES Continued 
 
 Hydrochloric acid, aq. sol. 1.222 
 
 Ice 0.917 
 
 Iceland spar 2.723 
 
 Iron, bar 7.788 
 
 Iron, cast 7.230 
 
 Iron, wrought 7.780 
 
 India-rubber 0.930 
 
 Iodine 4.950 
 
 Iron pyrites 5.000 
 
 Ivory 1.820 
 
 Lard 0.947 
 
 Lead, cast 11.360 
 
 Lead, sheet .... 11.400 
 
 Lignum vitse 1.333 
 
 Lime, quick 0.843 
 
 Limestone 3.180 
 
 Logwood 0.913 
 
 Magnesium 1.750 
 
 Mahogany . . . 0.56 to 0.852 
 
 Maple 0.755 
 
 Marble 2.720 
 
 Mercury 13.596 
 
 Milk -. . 1.032 
 
 Molasses 1.426 
 
 Mortar, average .... 1.700 
 
 Naphtha 0.848 
 
 Nitric acid . . . 1.38 to 1.559 
 Oak, American red . . . 0.850 
 Oak, American white . . 0.779 
 Oak, live, seasoned . . . 1.068 
 Oak, live, green .... 1.260 
 
 Oil, castor 0.970 
 
 Oil, linseed 0.940 
 
 Oil, olive 0.915 
 
 Oil, turpentine .... 0.870 
 
 Oil, whale 0.923 
 
 Paraffin . . . 0.824 to 0.940 
 Petroleum . . 0.836 
 
 Phosphorus . . 
 Pear-tree . . . 
 Pine, red, dry . . 
 Pine, white, dry . 
 Pine, yellow, dry . 
 
 . 1,830 
 . 0.660 
 . 0.590 
 . 0.554 
 . 0.461 
 
 Pine, pitch 0.660 
 
 Pitch . . . 1.150 
 
 Platinum wire .... 21.531 
 
 Poplar, common .... 0.389 
 
 Porcelain, china .... 2.380 
 
 Potassium 0.865 
 
 Quartz 2.650 
 
 Rock salt 2.257 
 
 Saltpeter . . . . . .2.100 
 
 Sand, quartz 2.750 
 
 Sand, river 1.880 
 
 Sand, fine 1.520 
 
 Sand, coarse 1.510 
 
 Silver, cast . . 10.424 to 10.511 
 
 Slate 2.880 
 
 Sodium 0.970 
 
 Steel, unhammered . . . 7.816 
 
 Sugar, cane 1.593 
 
 Sulphur, native .... 2.033 
 
 Sulphuric acid 1.840 
 
 Tallow 0.940 
 
 Tar 1.015 
 
 Tin, cast 7.290 
 
 Tourmaline, green . . . 3.150 
 
 Vinegar 1.026 
 
 Water, at 100 C. . . . 0.958 
 
 Walnut 0.680 
 
 Water, sea 1.027 
 
 Wax, white 0.970 
 
 White metal, Babbitt . . 7.310 
 
 Willow . 0.585 
 
 Zinc, cast 7.000 
 
266 APPENDIX 
 
 XIII. TABLE OF SOLUBILITIES* 
 
 Showing the classes to which the compounds of the commonly 
 occurring elements belong in respect to their solubility in water, 
 hydrochloric acid, nitric acid, or aqua regia. 
 
 Preliminary JRemarks 
 
 For the sake of brevity, the classes to which the compounds 
 belong are expressed by letters, as follows : 
 
 W or w, soluble in water. 
 
 A or a, insoluble in water, but soluble in hydrochloric acid, 
 nitric acid, or in aqua regia. 
 
 I or i, insoluble in water, hydrochloric acid, or nitric acid. 
 
 Further, substances standing on the border lines are in- 
 dicated as follows : 
 
 W-A or w-a, difficultly soluble in water, but soluble in 
 hydrochloric acid or nitric acid. 
 
 W-I or w-i, difficultly soluble in water, the solubility not 
 being greatly increased by the addition of acids. 
 
 A-I or a-i, insoluble in water, difficultly soluble in acids. 
 
 If the behavior of a compound to hydrochloric and nitric 
 acids is essentially different, this is stated in the notes. 
 
 Capital letters indicate common substances used in the 
 arts and in medicine, while the small letters are used for 
 those less commonly occurring. The salts are generally con- 
 sidered as normal, but basic and acid salts, as well as double 
 salts, in case they are important in medicine or in the arts, 
 are referred to in the notes. The small numbers in the 
 table refer to notes on the following pages. 
 
 Notes to Table of Solubilities 
 
 1. Potassium dichromate, W. 
 
 2. Potassium borotartrate, W. 
 
 3. Hydrogen potassium oxalate, W. 
 
 4. Hydrogen potassium carbonate, W. 
 
 * Taken from Wells' translation of the 16th German edition of Fresenius' 
 Qualitative Analysis. 
 
APPENDIX 
 
 267 
 
 SOLUBILITY TABLE 
 
 
 Potassium 
 
 Sodium 
 
 Ammonium 
 
 Barium 
 
 Strontium 
 
 Calcium 
 
 Magnesium 
 
 Aluminium 
 
 Oxide .... 
 
 W 
 
 W 
 
 W 
 
 W 
 
 w 
 
 W-A 
 
 A 
 
 A 
 
 Chromate . . . 
 
 W, 
 
 w 
 
 w 
 
 a 
 
 w-a 
 
 w-a 
 
 w 
 
 
 Sulphate . . . 
 
 ^13.15 
 
 W 
 
 "Wt4 20-30 
 
 I 
 
 I 
 
 W-I 
 
 W 
 
 W 13 . M 
 
 Phosphate . . 
 
 W 
 
 W 8 
 
 W8-12 
 
 a 
 
 a 
 
 A u 
 
 a J2 
 
 a 
 
 Borate .... 
 
 W 2 
 
 * 
 
 W 
 
 a 
 
 a 
 
 a 
 
 w-a 
 
 a 
 
 Oxalate . . . 
 
 W 3 
 
 W 
 
 W 
 
 a 
 
 a 
 
 A 
 
 a 
 
 a 
 
 Fluoride . . . 
 
 W 
 
 w 
 
 W 
 
 w-a 
 
 w-a 
 
 A-I 
 
 a-i 
 
 w 
 
 Carbonate . . 
 
 W 4 
 
 W 10 
 
 W 
 
 A 
 
 A 
 
 A 
 
 A 
 
 
 Silicate .... 
 
 W 
 
 w 
 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a-i 
 
 Chloride . . . 
 
 W 37 
 
 ^35 
 
 W 21 .38 
 
 W 
 
 W 
 
 W 
 
 W 
 
 w 
 
 Brotnid.6 , 
 
 Hf\f\if\a 
 
 W 
 
 
 W 
 
 
 
 
 
 
 1OU1U6 .... 
 
 Cyanide . . . 
 
 W 
 
 W 
 
 w 
 
 \v-a 
 
 w 
 
 w 
 
 w 
 
 
 Ferrocyanide 
 
 W 
 
 w 
 
 w 
 
 w-a 
 
 w 
 
 w 
 
 w 
 
 
 Ferricyanide . . 
 
 W 
 
 w 
 
 w 
 
 
 
 w 
 
 w 
 
 
 Thiocyanate . . 
 
 W 
 
 w 
 
 W 
 
 w 
 
 w 
 
 w 
 
 w 
 
 
 Sulphide . . . 
 
 W 
 
 W 
 
 W 
 
 W 
 
 w 
 
 W-A 45 
 
 a 
 
 a 
 
 Nitrate . . . 
 
 W 
 
 W 
 
 W 
 
 W 
 
 W 
 
 w 
 
 w 
 
 w 
 
 Chlorate . . . 
 
 W 
 
 w 
 
 w 
 
 w 
 
 W 
 
 w 
 
 w 
 
 w 
 
 Tartrate . . . 
 
 W B . 6 . 7. 22 46 
 
 W 7 
 
 ^6 
 
 a 
 
 a 
 
 A 
 
 w-a 
 
 w 
 
 Citrate .... 
 
 W 
 
 w 
 
 W 
 
 a 
 
 a 
 
 w-a 
 
 w 
 
 w 
 
 Malate .... 
 
 W 
 
 w 
 
 W 
 
 w&a 
 
 w 
 
 w-a 47 
 
 w 
 
 w 
 
 Succinate . . . 
 
 w 
 
 w 
 
 w 
 
 w-a 
 
 w-a 
 
 w-a 
 
 w 
 
 w-a 
 
 Benzoate . . . 
 
 W 
 
 w 
 
 w 
 
 w 
 
 
 w 
 
 w 
 
 
 Salicylate . . . 
 
 w 
 
 W 
 
 W 
 
 w-a 
 
 w-a 
 
 w-a 
 
 w 
 
 
 Acetate . . . 
 
 W 
 
 W 
 
 W 
 
 W 
 
 w 
 
 W 
 
 w 
 
 W 
 
 Formate . . . 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 Arsenite . . . 
 
 W 
 
 w 
 
 w 
 
 a 
 
 a 
 
 a 
 
 a 
 
 
 Arsenate . . . 
 
 W 
 
 W 
 
 w 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 5. Hydrogen potassium tartrate, W. 
 
 6. Ammonium potassium tartrate, W. 
 
 7. Sodium potassium tartrate, W. 
 
 8. Ammonium sodium phosphate, W. 
 
 9. Acid sodium borate, W. 
 
 10. Hydrogen sodium carbonate, W. 
 
 11. Tricalcium phosphate, A. 
 
 12. Ammonium magnesium phosphate, A. 
 
 13. Potassium aluminium sulphate, W. 
 
268 APPENDIX 
 
 SOLUBILITY TABLE Continued 
 
 
 Cromium 
 
 | 
 
 55 
 
 Manganese 
 
 3 
 
 i 
 
 g 
 
 1 
 
 O 
 
 Ferrous 
 
 B 
 
 E 
 
 
 
 1 
 co 
 
 , 
 
 Mercurous 
 
 Oxide 
 
 A&I 
 
 A 
 
 a !7 
 
 A 
 
 A 
 
 a 
 
 A 
 
 a 
 
 AM 
 
 A 
 
 Chromate .... 
 
 a 
 
 w 
 
 w 
 
 a 
 
 a 
 
 
 w 
 
 a 
 
 A-I 
 
 a 
 
 Sulphate .... 
 
 W&I ]5 
 
 W 
 
 W 
 
 W 
 
 W 
 
 w*, 
 
 W 
 
 W-A 
 
 A-I 
 
 w-a 
 
 Phosphate . . . 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 A 
 
 a 
 
 a 
 
 a 
 
 Borate 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 
 Oxalate .... 
 
 w-a 
 
 a 
 
 w-a 
 
 a 
 
 a 
 
 a 
 
 8 
 
 a 
 
 a 
 
 a 
 
 Fluoride .... 
 
 w 
 
 w-a 
 
 a 
 
 w-a 
 
 w-a 
 
 w-a 
 
 w 
 
 w 
 
 a 
 
 
 Carbonate .... 
 
 
 A 
 
 A 
 
 A 
 
 A 
 
 A 
 
 
 a 
 
 A 
 
 a 
 
 Silicate . . 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 
 a 
 
 
 Chloride .... 
 
 W&I 
 
 W 
 
 W 
 
 W 
 
 W 
 
 W 
 
 w 
 
 I 
 
 W-I 
 
 A-I 
 
 Bromide .... 
 
 w&i 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 i 
 
 w-i 
 
 a-i 
 
 Iodide . . . 
 
 W 
 
 w 
 
 <f 
 
 w 
 
 w 
 
 W 
 
 w 
 
 i 
 
 W-A 
 
 A 
 
 Cyanide .... 
 
 a 
 
 A 
 
 a 
 
 a-i 
 
 a-i 
 
 a-i 
 
 
 I 
 
 a 
 
 
 Ferrocyanide . . 
 
 
 A-I 
 
 a 
 
 i 
 
 i 
 
 i 
 
 I 
 
 i 
 
 a 
 
 
 Ferricyanide . . 
 
 
 a 
 
 i 
 
 i 
 
 i 
 
 I 
 
 w 
 
 i 
 
 w-a 
 
 
 Thiocyanate . . . 
 
 w 
 
 W 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 i 
 
 a 
 
 A 
 
 Sulphide .... 
 
 a-i 
 
 A H 
 
 A 
 
 Ha 
 
 19 
 
 A 
 
 a 
 
 * 
 
 A 
 
 A 
 
 Nitrate .... 
 
 W 
 
 w 
 
 w 
 
 w 
 
 W 
 
 w 
 
 w 
 
 W 
 
 W 
 
 w 
 
 Chlorate .... 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 Tartrate .... 
 
 w 
 
 a 
 
 w-a 
 
 a 
 
 w 
 
 w-a 
 
 W 22 
 
 a 
 
 a 
 
 w-a 
 
 Citrate 
 
 w 
 
 w-a 
 
 a 
 
 w 
 
 w 
 
 w 
 
 W 
 
 a 
 
 a 
 
 a 
 
 Malate 
 
 
 w 
 
 w 
 
 
 
 
 W 
 
 w a 
 
 w-a 
 
 a 
 
 Succinate .... 
 
 
 w-a 
 
 w 
 
 w 
 
 w-a 
 
 w-a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 Benzoate .... 
 
 
 
 w 
 
 
 
 w 
 
 a 
 
 w-a 
 
 a 
 
 a 
 
 Sa'licylate .... 
 
 
 
 
 
 
 
 
 w-a 
 
 w-a 
 
 
 Acetate .... 
 
 w 
 
 W 
 
 w 
 
 w 
 
 w 
 
 w 
 
 W 
 
 w 
 
 W 2 , 
 
 w-a 
 
 Formate .... 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 w 
 
 W 
 
 w 
 
 w-a 
 
 w 
 
 Arsenite .... 
 
 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 Arsenate .... 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 a 
 
 14. Ammonium aluminium sulphate, W. 
 
 15. Potassium chromium sulphate, W. 
 
 16. Zinc sulphide, as a sphalerite, soluble in nitric acid, 
 with separation of sulphur ; in hydrochloric acid only upon 
 heating. 
 
 17. Manganese dioxide, easily soluble in hydrochloric 
 acid ; insoluble in nitric acid. 
 
 18. Nickel sulphide is rather easily decomposed by nitric 
 acid ; very difficultly by hydrochloric acid. 
 
APPENDIX 
 
 269 
 
 SOLUBILITY TABLE Concluded 
 
 
 Mercuric 
 
 | 
 
 
 
 ^3 
 3 
 
 5 
 
 Cadmium 
 
 
 
 2 
 o 
 O 
 
 Platinum 
 
 Stannous 
 
 Stannic 
 
 Antimonious 
 
 Oxide 
 
 A 
 
 A 
 
 
 a 
 
 
 a 
 
 a 
 
 a&i 
 
 AM 
 
 Chromate . . . 
 
 w-a 
 
 W 
 
 
 a 
 
 
 
 a 
 
 
 "42 
 
 a 
 
 Sulphate .... 
 
 w, 7 
 
 Wao 
 
 W 
 
 W 
 
 
 w 
 
 w 
 
 
 a 
 
 Phosphate . . . 
 
 a 
 
 a 
 
 
 a 
 
 
 
 a 
 
 a 
 
 w-a 
 
 Borate .... 
 
 
 a 
 
 
 w-a 
 
 
 
 a 
 
 
 
 Oxalate .... 
 
 a 
 
 a 
 
 
 a 
 
 
 w 
 
 a 
 
 w 
 
 a 
 
 Fluoride .... 
 
 w-a 
 
 a 
 
 W 
 
 w-a 
 
 
 
 w 
 
 w 
 
 w 
 
 Carbonate . . . 
 
 a 
 
 A 
 
 a 
 
 a 
 
 
 
 
 
 
 Silicate .... 
 
 
 a 
 
 
 a 
 
 
 
 
 
 
 Chloride ..... 
 
 W 28 
 
 W 
 
 W-Agg 
 
 W 
 
 W SH 
 
 W 37-38 
 
 W 
 
 W 40 
 
 W-A 
 
 Bromide .... 
 
 w 
 
 w 
 
 w-a 
 
 W 
 
 w 
 
 W 
 
 
 
 w-a 
 
 Iodide 
 
 A 
 
 W 
 
 a 
 
 W 
 
 a 
 
 j 
 
 w 
 
 w 
 
 w a 
 
 Cyanide .... 
 
 W 
 
 a 
 
 
 a 
 
 W 
 
 W 
 
 
 
 
 Ferrocyanide . . 
 
 
 1 
 
 
 w-a 
 
 
 
 i 
 
 i 
 
 
 Ferricyanide . . 
 
 
 
 
 
 
 
 i 
 
 
 
 Thiocyanate . . 
 
 w 
 
 a 
 
 
 
 
 a 
 
 
 w 
 
 
 Sulphide . . . 
 
 A w 
 
 
 
 a 
 
 A ' 
 
 &3C 
 
 a 39 
 
 *41 
 
 a 41 
 
 A M . 4 5 
 
 Nitrate . . . 
 
 W 
 
 W 
 
 W* 
 
 w 
 
 
 W 
 
 
 
 
 Chlorate . . . 
 
 W 
 
 w 
 
 w 
 
 w 
 
 
 
 W 
 
 
 
 Tartrate . . . 
 
 a 
 
 W 
 
 a 
 
 w a 
 
 
 
 a 
 
 
 1*46 
 
 Citrate . . . 
 
 w-a 
 
 W 
 
 
 a 
 
 
 
 
 
 
 Malate . . . 
 
 w-a 
 
 w 
 
 
 
 
 
 w 
 
 w 
 
 
 Succinate . . 
 
 w-a 
 
 w 
 
 
 w 
 
 
 
 
 a 
 
 
 Benzoate . . 
 
 w-a 
 
 a 
 
 
 w 
 
 
 
 
 
 
 Salicylate . . 
 
 
 w 
 
 
 
 
 
 
 
 
 Acetate . . . 
 
 w 
 
 W M 
 
 w 
 
 w 
 
 
 
 w 
 
 w 
 
 
 Formate . . . 
 
 w 
 
 w 
 
 w 
 
 w 
 
 
 
 w 
 
 
 
 Arsenite . . . 
 
 a 
 
 A 
 
 
 
 
 
 
 
 a 
 
 Arsenate . . . 
 
 a 
 
 a 
 
 a 
 
 
 
 
 
 a 
 
 a 
 
 19. Cobalt sulphide, like nickel sulphide. 
 
 20. Ammonium ferrous sulphate, W. 
 
 21. Ammonium ferric chloride, W. 
 
 22. Potassium ferric tartrate, W. 
 
 23. Silver sulphide, only soluble in nitric acid. 
 
 24. Minium is converted by hydrochloric acid into lead 
 chloride ; by nitric acid into soluble lead nitrate and brown 
 lead peroxide which is insoluble in nitric acid. 
 
 25. Tribasic lead acetate, W. 
 
270 APPENDIX 
 
 26. Mercurius solubilis Ifahnemanni, A. 
 
 27. Basic mercuric sulphate, A. 
 
 28. Mercuric amido-chloride, A. 
 
 29. Mercuric sulphide, ijot soluble in hydrochloric acid, 
 nor in nitric a,cid, but soluble in aqua regia upon heating. 
 
 30. Ammonium cupric sulphate, W. 
 
 31. Copper sulphide is decomposed with difficulty by 
 hydrochloric acid, but easily by nitric acid. 
 
 32. Basic cupric acetate, partially soluble in water, and 
 completely in acids. 
 
 33. Basic bismuth chloride, A. 
 
 34. Basic bismuth nitrate, A. 
 
 35. Sodium auric chloride, W. 
 
 36. Gold sulphide is not dissolved by hydrochloric acid, 
 nor by nitric acid, but it is dissolved by hot aqua regia. 
 
 37. Potassium chlorplatinate, W-I. 
 
 38. Ammonium chlorplatinate, W-I. 
 
 39. Platinum sulphide is not attacked by hydrochloric 
 acid, is but slightly attacked by boiling nitric acid (if it has 
 been precipitated hot), but is dissolved by hot aqua regia. 
 
 40. Ammonium stannic chloride, W. 
 
 41. Stannous sulphide and stannic sulphide are decom- 
 posed and dissolved by hot hydrochloric acid, and are con- 
 verted by nitric acid into oxide, which is insoluble in an 
 excess of nitric acid. Sublimed stannic sulphide is dis- 
 solved only by hot aqua regia. 
 
 42. Antimonious oxide, soluble in hydrochloric acid, not 
 in nitric acid 
 
 43. Basic antimonious chloride, A. 
 
 44. Antimony sulphide is completely dissolved by hydro- 
 chloric acid, especially upon heating; it is decomposed by 
 nitric acid, but dissolved only to a slight degree. 
 
 45. Calcium antimony sulphide, W-A. 
 
 46. Potassium antimony tartrate, W. 
 
 47. Hydrogen calcium malate, W. 
 
APPENDIX 271 
 
 XIV. SOLUTIONS* 
 Acids 
 
 Cone. HCl, sp. gr. 1.2, 39 % HCl by weight. 
 
 Dil. HCl, 3 N, sp. gr. 1.05, 10 % HCl by weight. 
 
 Cone. HNO S , sp. gr. 1.42, 70 % HN0 3 by weight. 
 
 Dil HN0 3 , 3 N, sp. gr. 1.10, 10 % HN0 3 by weight. 
 
 Cone. H 2 SOt, sp. gr. 1.84, 98% H 2 S0 4 . 
 
 Dil. H. 2 $0 4 , 3 N, sp. gr. 1.09, 13% H 2 S0 4 . 
 
 Cone. HF, 40%. 
 
 Acetic Acid, 2 N, 120 g. of glacial acetic acid in 1 liter. 
 
 Tartaric Acid, 2 N, 150 g. in 1 liter. 
 
 Aqua Regia, 1 part of cone. HN0 3 to 3 parts cone. HCl ; 
 to be prepared only when needed. 
 
 H 2 S gas is prepared by the action of HCl (1 : 1) on FeS ; 
 the gas should be washed by passing it through water before 
 using. 
 
 Bases 
 
 Cone. Ammonia, sp. gr. 0.90, 28 % 
 
 Dil Ammonia, sp. gr. 0.96, 10 % NH 3 . 
 
 Sodium hydroxide, NaOH, 4 N. 
 
 As the material used for qualitative purposes contains 
 about 10 % of water, the amount needed for a 4 N solution 
 will be 4 x 40 x -V = 177.7 g. in 1 liter. 
 
 Potassium hydroxide, KOH, 4 N. 
 
 The grade used for analytical purposes contains about 
 20 % water ; hence the quantity needed for a 4 N solution 
 will be 4 x 56 x | = 280 g. in 1 liter. 
 
 Barium hydroxide, Ba(OH) 2 , saturated solution. 
 
 Calcium hydroxide, Ca(OH) 2 , saturated solution. 
 
 * Taken from Baskerville and Curtman's Qualitative Analysis, New 
 York, 1910. 
 
272 APPENDIX 
 
 Salts 
 
 Ammonium acetate, NH 4 C 2 H 3 2 . Add 1000 cc. of am- 
 monium hydroxide (sp. gr. 0.90), slowly and with constant 
 stirring, to 1250 cc. of glacial acetic acid. 
 
 Ammonium carbonate, (NH 4 ) 2 C0 3 S04 free. Dissolve, with- 
 out heating, 192 g. of the powdered salt in a mixture of 
 80 cc. of NH 4 OH (sp. gr. 0.90) and 500 cc. of water. When 
 solution is complete, dilute to 1 liter. The strength is ap- 
 proximately 4 N. 
 
 Ammonium chloride, NH 4 C1, 4 N. 214 g. in 1 liter. 
 
 Ammonium motybdate solution. To a mixture of 271 cc. 
 of cold distilled water and 144 cc. of NH 4 OH (sp. gr. 0.90), 
 add 100 g. Mo0 3 and stir till solution is complete ; slowly 
 add this solution with constant stirring to a mixture of 489 
 cc. HN0 3 (sp. gr. 1.42) and 1148 cc. of water. Allow the 
 mixture to stand for 24 hours and then decant the clear 
 liquid into a bottle. 
 
 Ammonium oxalate, (NH 4 ) 2 C 2 4 H 2 0. 35.54 g. in 1 liter. 
 
 Ammonium sulphide (colorless), (NH 4 ) 2 S. Saturate 3 
 parts of NH 4 OH with H 2 S, add 2 parts of ammonium hydrox- 
 ide, and dilute with an equal volume of water. 
 
 Ammonium sulphide (yellow), (1ST H^S.,.. Digest the color- 
 less undiluted (NH 4 ) 2 S with flowers of sulphur in the pro- 
 portion of 1 g. to the liter and then dilute with an equal 
 volume of water. 
 
 Ammonium sulphate, (NH 4 ) 2 S0 4 , N. 100 g. in 1 liter. 
 
 Barium chloride, BaCl 2 2 H 2 0, N. 122.17 g. in 1 liter. 
 
 Bromine water, saturated solution. 
 
 Calicum chloride, CaCl 2 , anhydrous, N. 55.6 g. in 1 liter. 
 
 Calcium sulphate, CaS0 4 - 2 H 2 0, saturated solution. 
 
 Chlorine water, saturated solution. 
 
 Cobalt nitrate, Co (N0 3 ) 2 6 H 2 0, for confirmatory tests for 
 Al and Zn. 0.5 g. in 1 liter. 
 
APPENDIX 273 
 
 Ferric alum, Fe 2 (S0 4 ) 3 (NH 4 ) 2 S0 4 - 24 H 2 O, saturated 
 solution. 
 
 Ferric chloride, FeCl 3 6 H 2 0,* 2 N. 180 g. in 1 liter. 
 
 Ferrous sulphate, FeS0 4 7 H 2 0. To be prepared in small 
 amounts as needed. 
 
 Hydroclilorplatinic acid, H 2 PtCl 6 6 H 2 0. 10 % solution. 
 
 Hydrogen dioxide, 3%. 
 
 Lead acetate, Pb(C 2 H 3 2 ) 2 3 H 2 0,f N. 189.5 g. in 1 liter. 
 
 Magnesia mixture. Dissolve 110 g. of MgCl 2 6 H 2 and 
 280 g. of NH 4 C1 in a liter of distilled water ; when solution 
 is complete, add 261 cc. of ammonium hydroxide (sp. gr. 
 0.90), then add enough water to make the volume 2 liters. 
 
 Mercuric chloride, HgCl 2 - Saturated solution. 
 
 Potassium acetate, KC 2 H 3 2 . Saturated solution. 
 
 Potassium chromate, K 2 Cr0 4 . N. 97.3 g. in 1 liter. 
 
 Potassium cyanide, KCN, N. 65.2 g. in 1 liter. 
 
 Potassium dichromate, K 2 Cr 2 7 , N. 73.8 g. in 1 liter. 
 
 Potassium ferrocyanide, K 4 Fe(CN) 6 , N. 105.7 g. in 1 liter. 
 
 T^T 
 
 Potassium iodide, KI, 83.1 g. in 1 liter. 
 J 
 
 Potassium nitrate. KN0 2 . 500 g. in 1 liter. 
 
 Potassium permanganate, KMn0 4 , N. 79.1 g. in 1 liter. 
 
 Potassium thiocyanate, KCNS, N. 97.2 g. in 1 liter. 
 
 Silver nitrate, AgN0 3 , 42.5 g. in 1 liter. 
 
 Silver sulphate, Ag S0 4 . Saturated solution. 
 
 Sodium acetate, NaC 2 H 3 2 , 4 N. 328 g. in 1 liter. 
 
 Sodium carbonate, Na 2 C0 3 (dry). Saturated solution. 
 
 Sodium cobaltic nitrite, Na 3 Co(]Sr0 2 ) 6 . Dissolve 100 g. 
 KaN0 2 in 300 cc. distilled water, slightly acidify with acetic 
 acid, and then add 10 g. of Co(N0 3 ) 2 6 H 2 0. Allow the 
 solution to stand for 24 hours and filter if necessary. As 
 the solution does not keep very well, only small amounts 
 should be prepared at a time. 
 
 * Should contain a little free HC1. t The solution should contain some 
 free acetic acid. 
 
274 APPENDIX 
 
 Sodium nitroprusside, Na 2 FeNO(CN) 5 - 2 H 2 0. 10 % solu- 
 tion. 
 
 Sodium phosphate, Na 2 HP0 4 - 12 H 2 0, N. 119 g. in 1 liter. 
 
 Sodium stannite, prepared as needed by adding to a little 
 SnCl 2 solution sufficient NaOH solution to redissolve the 
 precipitate which first forms. 
 
 Sodium thiosulphate, Na 2 S 2 O 3 5 H 2 0, N. 124 g. in 1 liter. 
 
 Stannic chloride, SnCl 4 , -^ 32.7 g. in 1 liter. 
 Stannous chloride* SnCl 2 2 H 2 0, ? 56.5 g. in 1 liter. 
 
 a 
 
 Stannous chloride (for Bettendorff Test). Dissolve 113 g. 
 of SnCl 2 2 H 2 O in 75 cc. of cone. HC1, and add a few pieces 
 of C. P. tin foil and keep in glass stoppered bottle. 
 
 Starch paste. Prepared as needed by mixing about 1 g. of 
 powdered starch with a little cold water to form a thin paste 
 and then adding it to 200 cc. of boiling water ; boil for a 
 minute, cool, and use. The solution does not keep, owing to 
 the growth of molds. It may be kept for some time, how- 
 ever, if a preservative such as CS 2 is added. 
 
 * Should contain a little free HC1. 
 
APPENDIX 
 
 275 
 
 XV. TABLE EMPLOYED IN THE PREPARATION OF 
 STANDARD STOCK SOLUTIONS* 
 
 
 
 
 
 
 Quantity of 
 
 a 
 s 
 g 
 
 Substance 
 
 Formular 
 Weight 
 
 Solubility 
 of Salt in 
 100 Pts. of 
 Cold Water 
 
 Per Cent 
 Metal 
 
 Salt to be 
 dissolved in 
 1 Liter to 
 give Strength 
 Ice. =100 ing. 
 
 
 
 
 
 
 
 of Metal 
 
 I 
 
 AffNOo 
 
 170 
 
 V. S.f 
 
 63.5 
 
 157 
 
 
 HgN0 3 .H 2 . . . 
 
 280 
 
 sol. in pres. of 
 HN0 3 
 
 71.5 
 
 140 
 
 
 Pb(N0 8 ) 2 .... 
 
 331 
 
 48 
 
 62.5 
 
 160 
 
 
 Pb(C 2 H 3 O 2 ) 2 -3H 2 O. 
 
 379 
 
 46 
 
 54.6 
 
 183 
 
 II 
 
 Hg(N0 8 ) 2 .J(H 2 0) . 
 
 333 
 
 sol. in pres. of 
 HN0 3 
 
 60 
 
 167 
 
 
 HffClo 
 
 271 
 
 7.4 
 
 74 
 
 135J 
 
 
 Bi(N0 3 ) 3 5 H 2 . . 
 
 484 
 
 sol. in pres. of 
 HNO S 
 
 43 
 
 233 
 
 
 Cu(N0 3 ) 2 6 H 2 . 
 
 295 
 
 V. S. 
 
 21.5 
 
 465 
 
 
 CuCl 2 2 H 2 . . . 
 
 170 
 
 120 
 
 37 
 
 270 
 
 
 CuSo 4 . 5 H 2 O . . . 
 
 249 
 
 40 
 
 25 
 
 400 
 
 
 Cd(NO 3 ) 2 .4H 2 O. . 
 
 308 
 
 v. s. 
 
 36 
 
 278 
 
 
 CdCl 2 .2H 2 . . . 
 
 219 
 
 140 
 
 51 
 
 196 
 
 
 3CdSO 4 -8H 2 . . 
 
 769 
 
 v. s. 
 
 43.5 
 
 230 
 
 
 AS 2 O 3 
 
 198 
 
 4. 
 
 75.5 
 
 ( )5 
 
 
 Na 2 HAsO 3 .... 
 
 170 
 
 V. S. 
 
 44 
 
 V Ji 
 
 227 
 
 
 Na 2 HAsO 4 -'12 H 2 O . 
 
 402 
 
 28 
 
 18.7 
 
 ( )ir 
 
 
 As 2 5 
 
 230 
 
 150 
 
 65 
 
 153 
 
 
 SbCl 3 
 
 226 
 
 sol. in pres. of 
 
 53 
 
 188 
 
 
 
 
 HC1 
 
 
 
 
 SnCl 2 -2H 2 . . . 
 
 225 
 
 V. S. 
 
 53 
 
 189 
 
 
 SnCl 4 -5H 2 O . . . 
 
 350 
 
 V. S. 
 
 34 
 
 294 
 
 
 SnCl 4 
 
 260 
 
 V. S. 
 
 46 
 
 218 
 
 
 
 
 
 
 
 * Taken from Baskerville and Curtman's Qualitative Chemical Analysis, 
 New York, 1910. 
 
 t Very soluble. 
 
 \ This amount readily dissolves in 1 liter of water containing .50 g. of 
 NaCl. 
 
 33 g. in 1 liter HC1 (1 : 1) gives strength 1 cc. = 25 mg. As. 
 IT 267 g. in 1 liter will give strength 1 cc. = 50 mg. As. 
 
276 
 
 APPENDIX 
 
 XV. TABLE EMPLOYED IN THE PREPARATION OF 
 STANDARD STOCK SOLUTIONS Continued 
 
 
 
 
 
 
 Quantity of 
 
 Q, 
 
 3 
 
 Substance 
 
 Forrnular 
 Weight 
 
 Solubility 
 of Salt in 
 100 Pts. of 
 Cold Water 
 
 Per Cent 
 Metal 
 
 Salt to be 
 dissolved in 
 1 Liter to 
 give Strength 
 Ice. = 1(10 mg. 
 
 o 
 
 
 
 
 
 of Metal 
 
 III 
 
 A1. 2 (S0 4 ) 3 .18H 2 . 
 
 666 
 
 107 
 
 8.1 
 
 ( ) 
 
 
 A1C1 3 -6H 2 . . 
 
 242 
 
 74 
 
 11.1 
 
 ( )t 
 
 
 A1(N0 3 ) 3 .8H 2 0. . 
 
 261 
 
 v. s. 
 
 10.3 
 
 970 
 
 
 Cr 2 (S0 4 ) 3 18 H 2 . 
 
 716 
 
 v. s. 
 
 14.6 
 
 690 
 
 
 K 2 Cr 2 (S0 4 ) 4 -24H 2 
 
 1000 
 
 20 
 
 5.2 
 
 ( )t 
 
 
 Cr(N0 3 ) 3 .9H 2 0. . 
 
 400 
 
 V. S. 
 
 13 
 
 770 
 
 
 CrCl 3 -6H 2 O . . . 
 
 206.5 
 
 v. s. 
 
 19.6 
 
 570 
 
 
 FeS0 4 -7H 2 . . . 
 
 278 
 
 60 
 
 20 
 
 500 
 
 
 Fe(N0 3 ) 3 .9H 2 . 
 
 404 
 
 v. s. 
 
 14 
 
 715 
 
 
 FeCl 3 -6H 2 O . . . 
 
 270 
 
 V. S. 
 
 20.7 
 
 482 
 
 
 Ni(N0 3 ) 2 -6H 2 0. . 
 
 291 
 
 50 
 
 20 
 
 500 
 
 
 NiCl 2 -6H 2 O . . . 
 
 238 
 
 V. S. 
 
 25 
 
 400 
 
 
 NiS0 4 7 H 2 O . . . 
 
 280 
 
 106 
 
 21 
 
 475 
 
 
 Co(NO 3 ) 2 -6H 2 O. . 
 
 291 
 
 V. S. 
 
 20 
 
 500 
 
 
 CoCl 2 -6H 2 O . . . 
 
 238 
 
 V. S. 
 
 245 
 
 407 
 
 
 CoSO 4 -7H 2 0. . . 
 
 281 
 
 50 
 
 21 
 
 475 
 
 
 MnS0 4 .4H 2 . . 
 
 223 
 
 123 
 
 25 
 
 400 
 
 
 MnCl 2 -4H 2 . . 
 
 198 
 
 150 
 
 28 
 
 360 
 
 
 Mn(NO 3 ) 2 -<>H 2 O . 
 
 287 
 
 v. s. 
 
 19 
 
 527 
 
 
 ZnSO 4 -7H 2 O. . . 
 
 288 
 
 135 
 
 22.5 
 
 445 
 
 
 Zn(N0 3 ) 2 .OH 2 . 
 
 298 
 
 V. S. 
 
 22 
 
 455 
 
 
 ZriCl 2 
 
 136 
 
 v. s. 
 
 48 
 
 208 
 
 
 
 
 
 
 
 IV 
 
 BaCl 2 .2H 2 O . . . 
 
 244 
 
 41 
 
 56 
 
 179 
 
 
 Ba(C 2 H 3 2 ) 2 H 2 . 
 
 273 
 
 63 
 
 50 
 
 200 
 
 
 Sr(N0 3 2 ) 2 . 4 H 2 . 
 
 284 
 
 40 
 
 31 
 
 324 
 
 
 Sr(NO 3 ) 2 .... 
 
 212 
 
 39 
 
 41.3 
 
 242 
 
 
 SrCl 2 -6H 2 O . . . 
 
 266 
 
 106 
 
 33 
 
 304 
 
 
 CaCl 2 
 
 111 
 
 v. s. 
 
 36 
 
 278 
 
 
 Ca(N0 3 ) 2 4 H 2 . 
 
 236 
 
 V. S. 
 
 17 
 
 590 
 
 *620 g. in 1 liter will give strength 1 cc. = 50 mg. Al. 
 1 450 g. in 1 liter will give strength 1 cc. = 50 mg. Al. 
 j; 192 g. in 1 liter will give strength 1 cc. = 10 mg. of Cr. 
 
APPENDIX 
 
 277 
 
 XV. TABLE EMPLOYED IN THE PREPARATION OF 
 STANDARD STOCK SOLUTIONS Conceded 
 
 
 
 
 
 
 Quantity of 
 
 CM 
 
 3 
 
 
 Substance 
 
 Formular 
 Weight 
 
 Solubility 
 of Salt in 
 100 Pts. of 
 Cold Water 
 
 Per Cent. 
 Metal 
 
 Salt to 'be 
 dissolved in 
 1 Liter to 
 give Strength 
 Ice. = 100 rag. 
 
 
 
 
 
 
 
 of Metal 
 
 V 
 
 MgS0 4 7 H 2 . . 
 
 246 
 
 77 
 
 9.7 
 
 ( ) 
 
 
 Mg(N0 3 ) 2 6 H 2 . 
 
 256.5 
 
 200 
 
 9.4 
 
 1060 
 
 
 MgCl 2 6 H 2 . . . 
 
 203.5 
 
 365 
 
 11.9 
 
 837 
 
 
 NaCl . 
 
 58 
 
 35 
 
 40 
 
 250 
 
 
 Na 2 HPO 4 -12H 2 O . 
 
 358 
 
 9.3 
 
 13 
 
 ( )t 
 
 
 NaNOj 
 
 85 
 
 80 
 
 27 
 
 371 
 
 
 KC1 
 
 75 
 
 32 
 
 52 
 
 192 
 
 
 KHSO 4 
 
 136 
 
 v. s. 
 
 28.5 
 
 350 
 
 
 KN0 3 
 
 101 
 
 31 
 
 39 
 
 257 
 
 
 NH 4 C1 
 
 53 
 
 33 
 
 34 
 
 294 
 
 
 (NH 4 ) 2 S0 4 .... 
 
 132 
 
 76 
 
 27.5 
 
 365 
 
 
 NH 4 NO 3 .... 
 
 80 
 
 200 
 
 22.5 
 
 445 
 
 
 (NH 4 ) 2 HP0 4 . . . 
 
 132 
 
 36.5 
 
 27.5 
 
 365 
 
 
 LiCl 
 
 42 
 
 80 
 
 16.7 
 
 600 
 
 
 LiNOg 
 
 69 
 
 48 
 
 10 
 
 ( )t 
 
 * 515 g. in 1 liter will give strength 1 cc. = 50 mg. Mg. 
 t 77 g. in 1 liter will give strength 1 cc. = 10 mg. Na. 
 J 500 g. in 1 liter will give strength 1 cc. = 50 mg. Li. 
 
278 
 
 APPENDIX 
 
 XVI. COMPARISON OF CALCULATED AND OBSERVED 
 DECOMPOSITION VOLTAGES OF VARIOUS AQUEOUS 
 SOLUTIONS 
 
 
 Chloride 
 
 Bromide 
 
 Iodide 
 
 Sulphate 
 
 Nitrate 
 
 Calculated 
 
 1 
 
 Calculated 
 
 1 
 
 Calculated 
 
 Observed 
 
 Calculated 
 
 TS 
 
 
 
 1 
 
 O 
 
 Calculated 
 
 1 
 o 
 
 1.98 
 
 Magnesium . . 
 Zinc 
 
 3.28 
 2 11 
 
 31 
 2.11 
 1.9 
 
 1.65 
 1.63 
 
 2.56 
 
 1.79 
 1.58 
 
 1.07 
 1.06 
 
 2.01 
 1.25 
 1.12 
 
 3.91 
 2.31 
 1.95 
 
 2.35 
 2.03 
 
 3.83 
 2.23 
 1.87 
 
 Cadmium . . . 
 
 2.03 
 
 Aluminium . 
 
 2.33 
 
 2.0 
 
 1.74 
 
 1.53 
 
 1.02 
 
 .88 
 
 
 
 1.10 
 
 
 Iron 
 
 1.78 
 
 1.6 
 
 
 1.30 
 
 
 .68 
 
 2.03 
 
 
 1.95 
 
 
 Cobalt .... 
 
 1.66 
 
 1.43 
 
 
 1.05 
 
 
 .51 
 
 1.91 
 
 1.92 
 
 1.84 
 
 
 Nickel. . . . 
 Tin 
 
 1.62 
 1.76 
 1.80 
 
 1.33 
 1.61 
 1.63 
 
 1.40 
 
 .85 
 1.30 
 1.33 
 
 .87 
 
 .36 
 .71 
 
 .83 
 
 1.89 
 
 2.09 
 
 1.81 
 1.48 
 
 1.52 
 
 Lead .... 
 
 Copper .... 
 Silver .... 
 
 143 
 
 1.28 
 
 1.32 
 1.11 
 
 1.09 
 .99 
 
 1.02 
 .95 
 
 .71 
 .60 
 
 .64 
 .65 
 
 1.22 
 .44 
 
 
 1.14 
 .365 
 
 .36* 
 
 Antimony . . 
 Bismuth . 
 
 1.32 
 1.31 
 
 1.22 
 1.21 
 
 
 .80 
 .92 
 
 
 .44 
 .43 
 
 
 
 
 
 Hydrogen . . 
 
 1.71 
 
 1.31 
 
 1.23 
 
 .94 
 
 .57 
 
 .52 
 
 1.70 
 
 1.67 
 
 1.81 
 
 1.69 
 
 The observed decomposition values of the acids given 
 under hydrogen, together with many of the sulphates and 
 nitrates, are taken from LeBlanc's Electro-Chemistry, pp. 
 247-248. The other observed values are from Crocker, 
 Trans. Am. Inst. E. E., 1885, p 281. 
 * Experiment. 
 
421 n