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 o==; 
 
 EW QUESTIONS AND 
 iLEMS IN CHEMISTRY
 
 UNIVERSITY OF CALIFORNIA 
 AT LOS ANGELES 
 
 GIFT OF 
 
 HERMAN FLECK
 
 REVIEW QUESTIONS AND 
 PROBLEMS IN CHEMISTRY 
 
 COMPILED BY 
 
 M. S. H. UNGER, A.M. 
 
 HEADMASTER OK ST. JOHNS SCHOOL, MANL1US, NEW YORK 
 
 GINN AND COMPANY 
 
 BOSTON NKW VoKK CHICAGO ]X)NDON
 
 COPYRIGHT, 1912, DY 
 M. S. H. UNGER 
 
 ALL RIGHTS RESERVED 
 812.11
 
 U5/Y 
 
 PREFACE 
 
 The fact is borne out by the experience of every teacher 
 J who has classes to prepare for college examinations, that the 
 ^ contents of the prevailing textbooks fail to furnish adequate 
 %> scientific material and drill to pass the entrance examina- 
 tions. The subject is so broad and the theories involved are so 
 \ complex, that the student often finds himself on the thresh- 
 N} old of the examination room completely bewildered by the 
 ' many facts, theories, laws, and details, and is entirely unable 
 , to make a scientific application of his knowledge. 
 
 This book has been prepared as a review of the theories 
 N, and laws of elementary chemistry, and there has been added 
 3 to each topic a sufficient number of problems to make a 
 "3 thorough application of the student's knowledge. It pre- 
 ^ sumes on the student's part a thorough acquaintance with 
 \ physical mixtures, laws of densities and specific gravity, laws 
 ^ of heat and electricity, the metric system, and an adequate 
 | training in some good textbook in elementary chemistry. 
 
 These questions and problems have been taken from the 
 
 ^> most recent college, College Board, and Regents of the State 
 
 of New York examinations, and from the latest and most 
 
 ^authoritative textbooks, and will be found from the author's 
 
 ^experience more than sufficient to prepare a student for the 
 
 ^entrance examinations for any college, or for the College 
 
 x Board examinations. 
 
 The questions and problems are classified so that a chapter 
 or parts of one may be taken up, in connection with the text- 
 book used in the class, for clinching the principles studied, 
 or the book may be used as a pre-examination review. It is 
 iii
 
 iv REVIEW QUESTIONS AND PROBLEMS 
 
 not necessary that the student should solve all the prob- 
 lems, but such selection should be made as will assure the 
 instructor that he is adequately prepared. 
 
 It must be observed in the use of the book that the 
 student must seek much necessary information from his 
 text, and there should be accessible several good textbooks 
 for handy reference. 
 
 Eeference to the appendixes will be found helpful in 
 solving many of the problems. 
 
 Acknowledgment is hereby made to the authors and pub- 
 lishers of the following textbooks, for the material obtained 
 from their publications : Lee's " Experimental Chemistry," 
 P. Blakiston's Son & Co. ; Linebarger's " Chemistry," Rand, 
 McNally & Company ; Newell's " Inorganic Chemistry " 
 and Baskerville and Estabrooke's " Problems in Chemistry," 
 D. C. Heath & Co. ; Brownlee and Others' " First Principles 
 of Chemistry," Allyn and Bacon ; Morgan and Ly man's 
 " Chemistry," The Macmillan Company ; McPherson and 
 Henderson's "Elementary Chemistry" and the publications 
 of the College Entrance Examination Board, Ginn and Com- 
 pany ; and to the authorities of the various universities, and 
 to the Board of Regents of the State of New York, whose 
 entrance examination questions have been used. 
 
 MAKLIUB, NKW YORK M - & H. UNGER
 
 CONTENTS 
 
 CHAPTER 
 
 
 PAGE 
 
 I. 
 
 PHYSICAL DEFINITIONS 
 
 1 
 
 II. 
 
 CHEMICAL DEFINITIONS 
 
 2 
 
 III. 
 
 PHYSICAL LAWS AND THEORY 
 
 4 
 
 IV. 
 
 CHEMICAL LAWS 
 
 5 
 
 V. 
 
 CHEMICAL THEORY 
 
 7 
 
 VI. 
 
 CHEMICAL DIVISION- 
 
 8 
 
 VII. 
 
 El ECTROLYTIC DlSSOCI \TION 
 
 14 
 
 VIII. 
 
 VALENCY 
 
 17 
 
 IX. 
 
 PERIODIC CLASSIFICATION 
 
 . 18 
 
 X. 
 
 HYDROGEN AND WATER 
 
 . 19 
 
 XI. 
 
 THE NITROGFN GROUP AND AIR 
 
 24 
 
 XII. 
 
 THE OXYGEN-SULPHUR GROUP 
 
 . 29 
 
 XIII. 
 
 THE CVRHON Sn ICON GROUP 
 
 34 
 
 XIV. 
 
 Tin: HALOGENS 
 
 41 
 
 XV. TllE Al.KAI.INE-EARTH METALS ...... 45 
 
 XVI. TIIE ALKALI METALS ......... 49 
 
 XVII. Tin: ALUMINUM-BORON GROUP ...... 52 
 
 XVIII. THE IRON, NICKEL, COIIALT, PLATINUM GROUP. 55 
 
 XIX. THE COPPER, SILVER, GOLD GROUP .... 57 
 
 XX. THE CHROMIUM-MANGANESE GROUP .... 60 
 
 XXI. ORGANIC ACIDS AND COMPOUNDS ..... 62 
 
 XXII. K(,M ATID.NS AND GENERAL FORMULAS. ... 64 
 
 XXI 1 1. (^ r LSI KINS AND CALCULATIONS: 
 
 A. PERCENTAGE COMPOSITION ...... 74- 
 
 B. ATOMIC AND MOLECULAR WEIGHTS . . 75 
 
 C. SIMPLEST FORMULAS ... ..... 77 
 
 D. MOLECULAR FORMULAS ....... 78 
 
 XXIV. WEIGHTS AND VOLUMES FROM EQUATIONS . . 81 
 
 XXV. MISCELLANEOUS QUESTIONS AND PROBLEMS. . 85 
 XXVI. PROP.LEMS ON MEASUREMENT, TEMPERATI I:K, 
 
 WEIGHT, AND DENSITY ........ !7 
 
 XXVII. APPENDIX . , 103
 
 REVIEW QUESTIONS 
 AND PROBLEMS IN CHEMISTRY 
 
 CHAPTER I 
 PHYSICAL DEFINITIONS 
 
 1. Define physical change and give two examples. 
 
 2. Define matter and energy, density, specific gravity. 
 
 3. Define element, mixture, compound, molecule, atom, 
 electron, ion, gas. 
 
 4. What are properties ? Mention those common to all 
 matter. If we had no senses, would we know anything 
 about the properties of substances ? 
 
 5. What forms of energy are possessed by a clock ? a 
 projectile ? a trolley car ? 
 
 6. When a certain amount of water freezes, does it absorb 
 or give off heat ? What difference in heat transfer takes 
 place when water drops in temperature from 2 to 1, and 
 from 1 to ? 
 
 7. Give examples of physical changes which are pro- 
 duced through the agency of heat ; of light ; of electricity ; 
 of chemical changes. 
 
 8. Define the difference between a mixture and a com- 
 pound, and illustrate each. 
 
 9. Give examples of gaseous mechanical mixtures and 
 of gaseous chemical compounds. Give similar examples, 
 liquid and solid, and point out the most important differ- 
 ence between compounds and mixtures. 
 
 1
 
 2 REVIEW QUESTIONS AND PROBLEMS 
 
 CHAPTER II 
 CHEMICAL DEFINITIONS 
 
 1. How does chemistry differ from physics ? What is 
 a chemical change ? 
 
 2. Define oxidation, reduction, kindling temperature, 
 decay. 
 
 3. How does combustion differ from decay and from 
 oxidation ? 
 
 4. What is a formula ? a reaction ? an equation ? a 
 radical ? 
 
 5. What is a flame ? What causes luminosity ? Why is 
 a Bunsen flame nonluminous ? 
 
 6. Define catalysis, molecule, electrolyte, nascent state, 
 allotropy. 
 
 7. Define deliquescence, efflorescence, electrolysis, and 
 illustrate each. 
 
 8. Define chemism, vapor density, isomerism, polym- 
 erism, absolute temperature. 
 
 9. Define hydroxide, alkali, metathetic reaction, solution. 
 
 10. Distinguish between crystals and water of crystalli- 
 zation ; between colloids and crystalloids ; between crystal- 
 line and amorphous. 
 
 11. Explain and illustrate deflagration, supersaturation, 
 fusion, sublimation. 
 
 12. What is meant by bivalent, monatomic, diatomic ? 
 
 13. State the meaning of distillation, filtrate, titration, 
 standard solution, indicator, neutral reaction. 
 
 14. Define the following terms: atom, valence, equivalent, 
 gram molecule, fermentation,.precipitation.
 
 CHEMICAL DEFINITIONS 3 
 
 15. Give three methods for collecting gases, and the con- 
 ditions under which each may be advantageously employed. 
 
 1 6. To what classes of changes do the following belong : 
 (<y) the melting of ice ? (//) souring of milk ? (c) explosion 
 of gunpowder? (rl) corrosion of metals? (e) burning of a 
 candle ? (/) ringing of a bell ? (f/) stretching of rubber ? 
 (7i) boiling of an egg ? (i) dissolving of sugar ? (j) decay 
 of meat ? (k) magnetizing of a nail ? 
 
 17. What is the property that distinguishes compounds 
 from mixtures ? What is an element ? What conditions 
 must be taken into account in measuring the volumes of 
 gases ? By what instruments are these conditions meas- 
 ured '.' (Jive the laws which express the effect of these 
 conditions. 
 
 18. Distinguish between chemical and physical properties ; 
 between elements, compounds, and mechanical mixtures ; 
 between metals and nonmetals ; between gases, liquids, and 
 solids ; between oxidation and reduction. 
 
 19. In the measurement of volumes of gases what do you 
 mean by standard conditions ? Should you consider it neces- 
 sary to make use of such conditions in measuring volumes 
 of liquids or solids ? Why ? 
 
 20. Describe two ways in which well-formed crystals are 
 obtained. How should you distinguish a crystalline from an 
 amorphous body ? 
 
 21. Explain the object of each of the following processes 
 and how each accomplishes the end in view : (a) evapora- 
 tion of a solution of a solid ; (b) filtration ; (<) distillation ; 
 ((/) pulverization before dissolving ; (e) sublimation. 
 
 22. Name two forms of energy that may produce chemical 
 changes, and give an example of a change caused by each. 
 
 23. Define each of the following and give an example of 
 each : () monobasic acid ; (lij dibasic acid ; (c) tribasic acid,
 
 4 REVIEW QUESTIONS AND PROBLEMS 
 
 and write the name and the formula of a salt formed from 
 each of the acids mentioned. 
 
 24. Define spontaneous combustion and explain the 
 phenomenon. 
 
 25. Define and illustrate molecular weight, anhydride, 
 deliquescence, antiseptic, precipitate, monad, occlusion. 
 
 26. Define and illustrate the following : binary com- 
 pounds, hydrate, base, dyad, compound radical, metal, neg- 
 ative element. 
 
 27. Define chemical change ; classify the different kinds 
 of chemical change, and give an example of each. 
 
 28. Define basic anhydride, acid anhydride, and give an 
 example of each. What is a dibasic acid ? 
 
 CHAPTER III 
 PHYSICAL LAWS AND THEORY 
 
 1. State and illustrate the relation that exists between 
 centigrade, Fahrenheit, and absolute-temperature scales. 
 
 2. State the formulas for converting temperatures. 
 
 3. Explain the meaning of the following statement : 
 " A gas is under standard conditions of temperature and 
 pressure." 
 
 4. State (a) Boyle's (Mariotte's) Law; (ft) the Law of 
 Charles. 
 
 5. Distinguish between and illustrate (a) law, (ft) theory, 
 (c) hypothesis. 
 
 6. What is (a) occlusion ? (ft) diffusion of gases ? 
 (c) spectrum analysis ? 
 
 7. What is. the kinetic theory of matter ?
 
 CHEMICAL LAWS 5 
 
 8. Define specific gravity or relative density, and show 
 how you would determine the specific gravity of a gas, a 
 liquid, and a solid. If the specific gravity of marble is 2.75, 
 how much in grams would a cubic meter of marble weigh ? 
 
 9. Explain in terms of the kinetic molecular theory the 
 difference between solids, liquids, and gases. 
 
 CHAPTER IV 
 CHEMICAL LAWS 
 
 1. State and illustrate the Law of Definite Proportions. 
 
 2. State and illustrate the Law of Multiple Proportions. 
 
 3. State the Law of Dulong and Petit. What use is 
 made of it by chemists ? 
 
 4. State the Periodic Law. What three striking predic- 
 tions made by Mendeleeff have since been verified ? 
 
 5. What is the basis of the Mendeleeff classification? 
 What evidence have we that this is a natural system ? Dis- 
 cuss the properties of the elements in some natural family 
 in such a way as to show this apparent relation. 
 
 6. Give the law for the conservation of matter; of 
 energy. 
 
 7. Give Hess's Law of Constant Heat Summation. 
 
 8. State the Law of Electrochemical Equivalents; the 
 Law of Equivalent Proportions. 
 
 9. State Graham's Law of Diffusion and Transpiration. 
 
 10. State the Law of Dal ton for a gaseous mixture. 
 
 11. What is the Law of Gay-Lussac ? Illustrate. 
 
 12. State Faraday's Laws of Electrolysis.
 
 6 REVIEW QUESTIONS AND PROBLEMS 
 
 13. Name four agencies that may bring about a chemical 
 change, and illustrate. 
 
 14. State the Law of Specific Heats. Illustrate its use by 
 an example. 
 
 15. What are Berthollet's Laws ? 
 
 16. What distinction would you make between a law and 
 a theory ? Give an illustration of each and tell why it is 
 thus classified. 
 
 17. The formulas of the five oxids of nitrogen are N 2 O, 
 NO, N 2 3 , N 2 4 , and N 2 O g . What simple ratio exists between 
 the varying weights of oxygen ? 
 
 18. State and illustrate Ampere's Law. Mention a method 
 of finding the molecular weight of a given compound when 
 its atomic weights are not known. 
 
 19. State what is meant by saying that the vapor density 
 of a gas is 44. 
 
 20. State Boyle's Law and Charles's Law. A certain 
 quantity of a gas occupies 1 1. at C. and 760 mm. Calculate 
 its volume at 20 C. and 750 mm. 
 
 21. State Avogadro's Law; also the Law of Multiple 
 Proportions. What volume of carbon dioxide would be 
 formed if 1 1. of acetylene (O^L^) burned in oxygen with 
 the formation of C0 2 and H 2 O ? 
 
 22. What is the law governing the combination of gases 
 by volume ? Give some examples illustrating the law. What 
 is the hypothesis advanced to explain it? Show how this 
 hypothesis gives rise to a method of expressing the weights 
 of molecules. 
 
 23. What evidence have we that matter is indestructible ? 
 If we cannot create matter, how are we to account for the 
 fact that the products of combustion of a candle weigh more 
 than the original caudle ?
 
 CHEMICAL THEORY 7 
 
 24. Give and illustrate two laws that lie at the founda- 
 tion of clicniica.1 knowledge. What law gives the basis for 
 calculating molecular weight ? 
 
 25. Give the characteristics of a chemical change, and 
 two important laws governing chemical change. 
 
 CHAPTER V 
 CHEMICAL THEORY 
 
 1. State the principle of Dal ton's Atomic Theory. 
 
 2. State the theory of Avogadro, and illustrate it by 
 the union of oxygen and hydrogen to form water, and of 
 hydrogen and chlorine to form hydrochloric acid. 
 
 3. Explain the theory of electrolytic dissociation. 
 
 4. Show how Avogadro's theory is used for determining 
 molecular and atomic weights. 
 
 5. Employ the Avogadro theory in calculating the atomic 
 weight of oxygen from the following data : carbonic, acid 
 gas, steam, laughing gas, and sulphurous anhydride contain, 
 in the order named, 72.73, 88.89, 36.364, and 50.00 per cent 
 by weight of oxygen ; their densities are, in the same order, 
 22, 9, 22, and 32. 
 
 6. Tell what substance and how much of it, in terms of 
 the atomic-molecular theory, is represented by each of the 
 following symbols and formulas : HC1, Ba, Fe, P 2 5 , O 2 , O g , 
 KOH, Zn(N0 8 ) 2 , I, SiO a . 
 
 7. State Gay-hussar's Law of the combining volumes of 
 gases and show how it led to Avogadro's hypothesis. 
 
 8. What is meant by (V/) the molecular weight of a gas, 
 and (/>) the density of a gas ? What relation exists between 
 the molecular weights and the densities of gases ? Illustrate.
 
 8 REVIEW QUESTIONS AND PROBLEMS 
 
 9. What evidence have we that one element can change 
 into another, and what explanation is offered ? 
 
 10. State the Law of (a) Definite Proportions ; (ft) Mul- 
 tiple Proportions. Show how the atomic hypothesis is 
 developed from these laws. 
 
 11. State Avogadro's hypothesis. Show how the molec- 
 ular weight of a given substance that can be volatilized may 
 be found by this hypothesis. 
 
 CHAPTER VI 
 CHEMICAL DIVISION 
 
 1. Define an acid, a base, and a salt, and give an example 
 of each. 
 
 2. Give the names of the following acids, and of the 
 potassium salt of each : HC1, HC10, HC1O 4 , HC10 3 , HN0 2 , 
 HN0 8 , H 2 S0 4 , HBr, H 8 As0 4 , HF. 
 
 3. What is a formula, a chemical equation, a reaction, a 
 graphic equation ? Illustrate. 
 
 4. Illustrate an endothermic and an exothermic reaction. 
 
 5. Illustrate and explain the difference between ana- 
 lytic, synthetic, and metathetic reaction. 
 
 6. Define and illustrate neutralization, normal salt, acid 
 salt, basic salt, an anhydride. 
 
 7. Give an example of a dibasic acid. Of H 2 S0 4 acting 
 (a) as an acid ; (ft) as a drying agent ; (c) as a strong acid 
 displacing a weaker one (equation). 
 
 8. Classify as (a) bases ; (ft) acids ; (r) salts : NaNO,, 
 NH 4 C1, HC10, NH 4 OH, BaS0 4 , Ca (NO,) 2 , HC10 4 , Sr(OH) 2 , 
 HN0 2 , Fe(OH) 8 .
 
 CIIK.MK AL DIVISION' 9 
 
 9. Write the formulas for the following compounds: 
 
 barium perclilorate. ammonium sulphate, strontium nitrate, 
 calcium sulphate, ferric sulphate, sodium perchlorate, cal- 
 cium hypochlorite, barium hydroxide, strontium oxide, 
 barium nitrate. 
 
 10. What is a primary salt? Write the formulas for 
 primary sodium sulphate, primary calcium phosphate, 
 secondary sodium carbonate. 
 
 11. How may hydrochloric acid be prepared? State the 
 properties of this acid. 
 
 12. Write the formulas for limestone, secondary sodium 
 phosphate, cupric sulphate, ammonia, aluminum phosphate, 
 mercurous chloride, barium nitrate, acetylene, gypsum, 
 marsh gas. 
 
 13. Write the formulas for sodium carbonate, lead sul- 
 phate, silica, arsine, arsenic trioxide, ammonium sulphide, 
 normal calcium phosphate. 
 
 14. Write the formulas for potassium chloride, sodium 
 carbonate, phosphoric acid, sodium cyanide, ferric oxide, 
 ferrous sulphide, ferric chloride, aluminum sulphate, cuprous 
 oxide, manganese dioxide. 
 
 15. Write the equation for the reactions that occur between 
 
 1. Potassium hydroxide and sulphuric acid. 
 
 2. Calcium hydroxide and ammonium sulphate. 
 
 3. Ferric chloride and ammonium hydroxide. 
 
 4. Sodium hydroxide and phosphoric acid. 
 
 5. Ammonium nitrate with heat. 
 
 17. Write the equations for the reactions between 
 
 1. Calcium carbonate and hydrochloric acid. 
 
 2. Potassium nitrate and sulphuric; acid.
 
 10 REVIEW QUESTIONS AND PROBLEMS 
 
 3. Copper and water vapor (heated). 
 
 4. Aluminum sulphate and ammonium hydroxide. 
 
 5. Calcium carbide and water. 
 
 18. Write the equations for the reactions : 
 
 1. Silver nitrate and sodium chloride. 
 
 2. Aluminum sulphate and potassium hydroxide. 
 
 3. Ammonium sulphate and slaked lime. 
 
 4. Sodium chloride, manganese dioxide, and sulphuric 
 
 acid. 
 
 5. Chlorine and potassium bromide. 
 
 6. Steam and incandescent coke. 
 
 7. Calcium hydroxide and carbon dioxide. 
 
 8. Methane and oxygen (ignited). 
 
 19. What is meant by the terms " saturated solution " and 
 " supersaturated solution " ? Under what conditions will 
 crystalline sodium sulphate effloresce ? 
 
 20. For what do the following symbols and formulas 
 stand : S0 2 , C, CH 4 , FeO, Fe 2 8 , CO 2 , CaC0 8 , Hg, I,, H 3 P0 4 , 
 NaOH, NH 4 , NH 3 , Ag, Al, 8 , S 6 , AsO g , SnO 2 , and Pb(OH) 2 . 
 
 21. Define basic anhydride and acid anhydride, and give 
 an example of each. 
 
 22. Classify the following substances as (") acids, (/>) bases, 
 or (e) salts, and give the name of each : H 2 S0 4 , KC1, KHS0 4 , 
 NH 4 OC1, NaOH, CaF 2 , HI, Ca(C10 3 ) 2 , NaN0 3 . 
 
 23. To what extent does the composition of a pure chemi- 
 cal compound vary ? Take as an example pure sodium 
 chloride from various sources, and mention other examples 
 if possible. 
 
 24. Give chemical names and molecular formulas for 
 the following substances : borax, Epsom salts, Glauber salts, 
 white vitriol, green vitriol, blue vitriol, iron pyrites, hematite, 
 magnetite, potash, galena, alum, gypsum, cryolite.
 
 < IIKMICAL DIVISION 11 
 
 25. Complete and balance : 
 
 2. A1(OH) 3 
 
 3. A.1(OH) 8 
 
 4. AgNO, + 
 
 5. CaC0 8 + C0 2 + H/) = 
 
 26. Complete the following, using symbols and formulas : 
 
 1. Ammonium hydroxide + hydrochloric acid = 
 
 2. Ammonia + hydrochloric acid = 
 
 3. Sodium chloride + silver nitrate = 
 
 4. Ferrous sulphide + sulphuric acid = 
 
 5. Lead nitrate + hydrogen sulphide = 
 
 6. Manganese dioxide 4- hydrochloric acid = 
 
 7. Calcium carbide + water = 
 
 8. Arsenic trioxide + nascent hydrogen = 
 
 9. Sodium carbonate + nitric acid = 
 
 10. Calcium hydroxide + carbon dioxide = 
 
 27. Explain the terms "ion" and " ionization." What 
 classes of substances are ionized when dissolved in water ? 
 I '> y what term are all such substances designated ? De- 
 tiiit 1 acid and base in terms of the theory of electrolytic 
 
 dissociation. 
 
 28. Explain by the ion theory the action of hydrochloric 
 ;icid on potassium hydroxide iii dilute solution. 
 
 29. Classify the given compounds under the following 
 headings: (") acids; (7>) bases; (V) normal salts; (V) acid 
 salts; (,<) anhydrides; (/) oxides: CO.,, NaHSO 4 , CaCl 2 , 
 1'bO, II :J P0 4 , Ca(OH) 2 , Na. 2 S0 8 , Mi,o.,.~SO,, NaOCl. 
 
 30. Write the chemical name ol each of the following: 
 
 white lead, blue \itriol, calomel, gypsum, saltpeter, caustic 
 potash, copperas.
 
 12 REVIEW QUESTIONS AND PROBLEMS 
 
 31. Distinguish in meaning between the following suffixes 
 when used in names of chemical compounds : (V/) <ms and ic ; 
 (f>) ite and ate. (c) When are hypo and per prefixed ? 
 
 32. Define each : (a) monobasic acid ; (b) dibasic acid ; 
 (V) tribasic acid. Write the name and the formula of a salt 
 formed from each of the acids mentioned. 
 
 33. Find the percentage composition of HNO g . Describe 
 a method -of preparing nitric acid, writing the reaction. 
 Mention its uses. 
 
 34. What substances do you employ in the laboratory 
 preparation of hydrochloric acid ? Why was each substance 
 selected ? Give the reason for the method used. 
 
 35. Write the chemical name of each of the following : 
 H 2 S0 8 , NaHC0 8 , H 2 S, Fe (S0 4 ) 3 , P 2 5 . 
 
 36. Complete the following equations, using formulas : 
 
 1. Sodium hydroxide + carbon dioxide = 
 
 2. Lead nitrate + hydrogen sulphide = 
 
 3. Calcium hydroxide + nitric acid = 
 
 4. Phosphorus + oxygen = 
 
 5. Sodium carbonate + calcium chloride = 
 
 6. Hydrogen + (hot) copper oxide = 
 
 State which of these compounds are (</) acids ; (7;) bases ; 
 (r) salts ; (rf) anhydrides. Which of the equations are exam- 
 ples of (e) oxidation ? (/) reduction ? (^/) double decom- 
 position ? (//,) neutralization ? 
 
 37. State how you could distinguish between 
 
 1. Concentrated and dilute sulphuric acid. 
 
 2. Sodium chloride and sodium sulphate. 
 
 3. Copper sulphate and potassium sulphate. 
 
 4. Platinum and magnesium. 
 
 5. Pulverized charcoal and manganese dioxide. 
 
 6. Hydrogen and carbon monoxide.
 
 CHEMICAL DIVISION 13 
 
 38. What determines whether a gas should be collected 
 (a) over water ? (ft) by downward displacement of air ? 
 (<) by upward displacement of air ? State the method used 
 in collecting ammonia, hydrogen sulphide, carbon dioxide, 
 nitric oxide. 
 
 39. Describe two ways in which well-formed crystals are 
 obtained. How should you distinguish a crystalline from 
 an amorphous body ? 
 
 40. Explain each of the following processes, and state 
 how each accomplishes the end in view : (.) evaporation of 
 a solution of a solid ; (It) filtration ; (<) distillation ; (<I) pul- 
 verization before dissolving ; (e) sublimation. 
 
 41. Describe experiments by which you could determine 
 whether 
 
 1. An alloy contained copper or silver. 
 
 2. A washing powder contained sodium carbonate. 
 
 3. A sample of potassium chlorate contained potas- 
 
 sium chloride. 
 
 4. A sample of material contained sand or lime. 
 
 5. A gas was nitrogen or carbon dioxide. 
 
 42. Distinguish between organic and inorganic chemistry ; 
 
 between metals and nonmetals. 
 
 43. Name the following acids and write the formula and 
 name Ihe sodium salt for each: 
 
 HI HNO 3 H 8 PO 2 H 2 S0 4 
 
 HIO, UNO, H 8 P0 8 H 2 S0 8 
 
 HI0 4 HNO H 8 P0 4 H a S a O 8 
 
 44. When perfectly dry sulphuric acid is treated with 
 perfectly dry sodium hydroxide, no chemical action takes 
 place. Why? 
 
 45. What is a radical '.' (Jive six examples.
 
 14 REVIEW QUESTIONS AND PROBLEMS 
 
 46. What are the main points of difference between 
 metals and nonmetals in the free state ? What chemical 
 property differentiates them as a rule ? Name some elements 
 which have properties of both. 
 
 47. Define acid and base. What is the important theo- 
 retical conception concerning solutions ? What is the mean- 
 ing of the terms " weak " and " strong " as applied to these 
 substances ? Define hydrolysis. 
 
 48. State the differences between the solutions obtained 
 by passing dry ammonia gas into water and sulphur dioxide 
 into water. What is the result if each solution is evaporated 
 separately? Explain. What is obtained when the solutions 
 are mixed and evaporated to dryness ? 
 
 49. What weight of Ca(OH). 2 can be prepared from 1 kg. 
 of quick lime, and what weight of HC1 will be neutralized 
 by the Ca(OH) 2 thus made ? 
 
 CHAPTER VII 
 ELECTROLYTIC DISSOCIATION 
 
 1. Describe in full what happens when a solution of 
 sodium sulphate is electrolyzed. 
 
 2. Describe in detail what takes place when an electric 
 current is passed through water that has been acidulated 
 with sulphuric acid. 
 
 3. Explain what takes place when a solution of copper 
 sulphate is electrolyzed with a copper cathode and ;i copper 
 anode. What commercial use is made of this process ? If 
 both terminals were platinum. 
 
 4. Explain the terms "ion" and " ioni/ation." What 
 classes of sul (stances are ioni/.ed when dissolved in water?
 
 ELECTROLYTIC DISSOCIATION 15 
 
 1 5 y what term arc all such substances designated ? Define acid 
 and base in terms of the theory of electrolytic dissociation. 
 
 5. Explain by the ion theory the action of hydrochloric 
 acid on potassium hydroxide in dilute solution. 
 
 6. How would you determine whether a given solution 
 is an electrolyte ? 
 
 7. To bring about a reaction between dry substances, 
 why is it necessary to place them in water? 
 
 8. Distinguish carefully between an ion of sodium and 
 an atom of sodium. 
 
 9. Explain the fact that sulphuric acid is less active 
 than nitric acid. 
 
 10. Give the conditions under which a reaction goes on 
 to completion. 
 
 11. If a certain current of electricity deposits 31.7 g. of 
 copper, ( ) how much silver would it deposit ? (/>) how 
 much zinc? 
 
 12. From the standpoint of the theory of electrolytic disso- 
 ciation () write the simple equation for a dilute solution of 
 copper sulphate ; this is a blue solution, (i) In the same man- 
 ner write one for sodium sulphate ; this is a colorless solu- 
 tion. How would you account for the color in the first case ? 
 
 13. Why will vegetables cook faster when boiled in strong 
 salt water than when boiled in pure water ? 
 
 14. Write equations showing how the following substances 
 ionize: HC1; HNO g ; NaOH; Ca(OH) 2 ; ZuS0 4 ; Fe(NO 8 ) a . 
 
 15. Write ionic equations for the interactions of the fol- 
 lowing substances. Do the reactions run to equilibrium or 
 to completion ? Why in each case ? 
 
 1. NaOH + HC1 - 4. BaCl 2 + Na 2 S0 4 - 
 
 2. Na 3 CO s + HN0 3 - 5. Ca (OH) 2 + H 2 SO 4 - 
 
 3. Ca(OH) 2 + HC1 - 6. AgNO, + HC1 -
 
 16 REVIEW QUESTIONS AND PROBLEMS 
 
 16. Why do less volatile acids decompose the salts of 
 more volatile acids and liberate the latter? 
 
 17. Why does liquid chlorine possess no acid properties ? 
 Would you expect it to conduct an electric current ? 
 
 18. Salt dissolved in pure water conducts electricity; 
 sugar does not. Explain according to modern views. 
 
 19. Describe the changes undergone by a solution of 
 sodium sulphate (colored with litmus) when subjected to 
 the action of a current of electricity. How may the direc- 
 tion of the current be determined ? 
 
 20. Define the term " electrolysis." Explain briefly by 
 means of a diagram what takes place when an electric current 
 is passed through a solution of common salt. 
 
 21. Define dissociation. Describe a laboratory experiment 
 to illustrate the dissociation of a chemical compound by the 
 aid of electricity. 
 
 22. What important difference is there between the be- 
 havior of table salt and that of sugar when dissolved 
 in water ? How may the peculiar behavior of salt be 
 shown? Name some of the substances which behave in 
 this manner. 
 
 23. Define an ion and an electrolyte. 
 
 24. A current deposits 1 g. of sodium ; find the weight 
 of Ni deposited by the same current. 
 
 25. How many grams of Ag will be deposited from a solu- 
 tion of AgN0 8 by a current of 2 amperes in 30 minutes ? 
 
 26. How much would a metal plate increase in weight if 
 it were nickel-plated by a current of 0.5 ampere running 
 5 hours ? 
 
 27. If the specific resistance of Ca is 0.000001629, what 
 is the resistance of a wire 200 in. long having a cross section 
 of 2 mm. 2 ?
 
 VALENCY 17 
 
 28. Gladstone and Hibbert on passing the same electric 
 current through solutions of zinc and silver obtained quan- 
 tities of the metals in the ratio of (Zn) 1 : (Ag) 3.298. If 
 the equivalent of silver is 197.94, what is that of zinc ? 
 
 29. When sulphuretted hydrogen is added to a solution 
 of ZnS0 4 , why is the zinc not completely precipitated as 
 sulphide ? How may the precipitation be made approxi- 
 mately complete? Explain by means of the hypothesis of 
 electrolytic dissociation and the law of mass action. 
 
 CHAPTER VIII 
 VALENCY 
 
 1. For what do the following symbols and formulas 
 sfciml: S0 2 , C, CH 4 , Fe 2 3 , C0 2 , CaC0 8 , Hg, I 2 , H g P0 4 , 
 Nat HI, (OH), (NHJ, NH 8 , Ag, Al, 8 , S 6 , As 2 8 , Sn0 2 , and 
 Pb(OH) 2 ? 
 
 2. Complete and balance : 
 
 1. NaOH + H 2 S0 4 = 
 
 2. Mg + HCl = 
 
 3. Na + H 2 O = 
 
 4. NaN0 8 +NH 4 Cl + H.E.= 
 
 5. NaCl + Mn0 2 + H 2 S0 4 + H.E.= 
 NOTE. H.E. stands for heat energy. 
 
 3. What is meant by saying that a chemical equation 
 " balances" ? Why is it incorrect if it does not " balance" ? 
 
 4. AVhat is valence ? What is the valence of iron in Fe0 8 , 
 and of silicon in SiH 4 ? What is meant by saying that an 
 element occurs in different allotropic forms ? 
 
 5. Define valence. State and illustrate the theory of 
 valence.
 
 18 REVIEW QUESTIONS AND PROBLEMS 
 
 6. If 1 1. of bromine vapor weighs 7.2 g. and if 1 g. of H 
 combines with 80 g. of bromine, what is the valency of 
 bromine ? 
 
 7. The valency of the following elements is indicated by 
 the number of accents : Na', K', Ca", Al'". What are the 
 formulas of the chlorides and the oxides of each of the 
 elements if Cl is univalent and is bivalent? 
 
 8. How many liters of hydrogen gas can be obtained 
 from 4 1. of HC1 acid gas ? 
 
 CHAPTER IX 
 
 PERIODIC LAW AND THE CLASSIFICATION OF THE 
 ELEMENTS 
 
 1. State the Periodic Law. What three striking predic- 
 tions made by Mendeleeff have since been verified ? 
 
 2. Discuss the periodic classification of the elements. 
 What evidence have we that this is a natural system ? -Dis- 
 cuss the properties of the elements in some natural family 
 in such a way as to show their apparent relation. 
 
 3. Name the important services the law (periodic) lias 
 rendered to chemistry. 
 
 4. What property of an element determines its position 
 in the periodic. arrangement of the elements? 
 
 5. Arrange the following elements in groups according 
 to some natural classification : aluminum, barium, iron, 
 phosphorus, silicon, sodium, sulphur. 
 
 6. What is the difference between the Periodic Law and 
 the Periodic System ? 
 
 7. State the characteristics of the alkali group; of the 
 halogen group; of the carbon group; of the argon group.
 
 HYDROGEN AM) WATER 19 
 
 8. If lead is an element and radium is an element, what 
 is tin- most significant difference between them? 
 
 9. What reasons are there for thinking that there may 
 be only one form of matter ? 
 
 10. Suppose that an element were discovered that filled 
 the blank in Group VI, Period 9, Family 13 (see Appendix), 
 what properties would it have ? 
 
 CHAPTER X 
 
 HYDROGEN AM) WATER 
 
 1. (u) Give two physical and two chemical properties of 
 JL. (//) Name two metals which displace H from dilute HC1, 
 and two that do not. 
 
 2. State (Jay-hussar's Law of Volumes and illustrate it 
 by a consideration of the union of H and Cl. Show by 
 Avogadro's theory and the foregoing law that a molecule 
 of II contains at least two atoms. 
 
 3. What volume of H measured under standard con- 
 ditions is required to reduce 11.94 g. of CuO ? What is 
 the weight and what the volume of the water (liquid) 
 formed '.' 
 
 4. -> H 2 + O a = 2H 2 0. What does this equation signify 
 in regard to (<y) molecules, (ft) the weights, and (c) the gas 
 volumes of the reacting substances and of the product ? 
 
 5. How many grams of the metal Zn are necessary for 
 the production, by the action of hydrochloric acid on the 
 metal, of 90 1. of H measured under standard conditions ? 
 
 6. 30 cc. of H is mixed with 40 cc. of air that contains 
 20 per cent of (), and the mixture is ignited. What gases 
 remain after explosion and what is the volume of each?
 
 20 REVIEW QUESTIONS AXD PROBLEMS 
 
 7. When H and unite, state the relation of the volume 
 of steam produced to the volumes of H and used. State 
 the law thus illustrated. 
 
 8. A tube containing copper oxide (CuO) weighs with 
 its contents 63 g. This tube is heated to redness and H 
 passed through it. When cooled the tube with its contents 
 is again weighed, and the weight is now found to be 60 g. 
 \Vhat volume of H measured under standard conditions has 
 united with the of the copper oxide ? 
 
 9. How may water be freed (a) from insoluble solid 
 matter ? (U) dissolved salts ? (c) dissolved air ? 
 
 10. Give the formulas of a compound of H and S and 
 of two oxides of sulphur. Show by equations how each of 
 these oxides of S would react with a water solution of 
 NaOH. 
 
 11. Give the volume relations between the gases in the 
 following reactions : hydrogen and chlorine combining to 
 form hydrochloric acid ; hydrogen and oxygen to form 
 steam ; hydrogen and nitrogen to form ammonia. If a 
 million molecules of H took part in each reaction, how 
 many molecules of each product would be formed ? 
 
 12. If to 36 g. of water at ordinary temperature we add 
 metallic sodium until no further reaction takes place, what 
 weight of H will be set free ? What volume will it occupy 
 at 18 and 740 mm. ? What proportions of the H originally 
 contained in the water will it constitute ? What weight 
 of Na will suffice ? How many gram-atoms of Na will 
 this be ? How many gram-molecular volumes will the H 
 occupy ? 
 
 13. Show how the composition of water may be deter- 
 mined by weight and by volume. 
 
 14. Distinguish between hard and soft waters. How are 
 lianl \\airrs sol'tcucd '.' I low do we obtain pure water?
 
 HYDROGEN AND WATER 21 
 
 How does pure water at ordinary room temperature behave 
 when heated to 100 C. or cooled to C. ? 
 
 15. Describe the process by which water may be decom- 
 posed by electrolysis, touching on apparatus generally used 
 and method of collecting the resulting gases. Name the 
 gases and give the test for each. 
 
 16. What is meant by a solution of a substance ? Describe 
 an experiment illustrating (a) saturated solution; (b) a 
 supersaturated solution. 
 
 17. Distinguish in composition between water of perma- 
 nent hardness and that of temporary hardness, and state 
 how each may be softened. 
 
 18. Dumas and Stas obtained the result of nineteen deter- 
 minations of the gravimetric composition of water to be an 
 average of 840.161 g. of formed from 945.439 g. of water. 
 Calculate the ratio of combination. 
 
 19. If crystallized calcium sulphate contains about 18 per 
 cent of water, what volume of steam at 200 C. and 755 mm. 
 is given off by heating 100 g. of the solid until all the water 
 of crystallization is expelled ? 
 
 20. Calculate the volume of 1 g. of H under standard 
 conditions. 
 
 21. Iron and tin ores usually are oxides. In obtaining 
 the metals Avhat kind of reactions are used ? 
 
 22. What changes would take place in nature if water did 
 not expand (rr) when cooled below 4 C. ? (&) when it freezes ? 
 
 23. The gas density of water vapor is about 9. Calculate 
 the volume occupied by 1 g. of water when in the form of 
 si cam at 100. When the steam is doubled in volume, to 
 what temperature would it have 1o le heated? 
 
 24. How could you determine the total amount of solid 
 material contained in a sample of water ?
 
 22 REVIEW QUESTIONS AND PROBLEMS 
 
 25. How may it be ascertained by experiment that water 
 contains the elements hydrogen and oxygen and these two 
 elements only ? 
 
 26. What weight of H will be required for the complete 
 reduction of 10 g. of CuO ? At 740mm. and 15 C. what 
 will be the volume of the H ? 
 
 27. What is meant by " water of crystallization," and 
 what relation does it bear to the terms "efflorescence" and 
 " deliquescence " ? 
 
 28. Describe three methods of obtaining hydrogen by the 
 decomposition of water. 
 
 29. Describe the essential features of the " mechanical 
 nlethod " of water filtration. 
 
 30. How may impure water be rendered fit for drinking 
 purposes ? 
 
 31. How would you prove that the composition of water 
 is expressed by the formula H 2 ? 
 
 32. A liter of H weighs 0.0899 g. A liter of oxygen 
 weighs 1.429 g. Explain the significance of the term "atomic 
 weight," and explain the calculation of the atomic weight 
 of from the above data. 
 
 33. Describe an experiment illustrating the solubility of 
 ammonia in water. 
 
 34. One volume of oxygen at 80 C. will go to form how 
 many volumes of steam under the same conditions ? How 
 will the number of molecules of each compare ? What in- 
 ference can be drawn from the last answer as to the char- 
 acter of the molecule ? How do we account for the 
 increase in the density when is converted into ozone ? 
 
 35. To what constituent do acids owe their characteris- 
 tic properties? Does this substance impart these proper- 
 ties to all its compounds ? What is the theory advanced
 
 HYDROGEN AND WATER 23 
 
 to explain the facts embraced in your answer ? How do we 
 explain the fact that some acids are stronger than others ? 
 Name some other facts which the above-mentioned theory 
 explains. 
 
 36. What weight of Zn would be required for the pro- 
 duction of sufficient H at 21 C. and 745 mm. pressure to fill 
 a balloon with a capacity of 100 cc. ? 
 
 37. Make a sketch of an apparatus employed for the 
 electrolysis of water; explain the process and state the 
 significance of the result. 
 
 38. State all that takes place when steam is passed over 
 heated iron. How may the gaseous product of the reaction 
 be identified ? Make a sketch of the apparatus which might 
 be used to carry out this experiment. Making use of the 
 solid product, outline an experiment to illustrate the pro- 
 duction of water. 
 
 39. How much sodium by its action upon water is required 
 to furnish 76 1. of H at 100 C. and 746 mm. ? 
 
 40. How may it be shown experimentally that ammonia 
 consists of H and N ? 
 
 41. What are hydrazine and hydrazoic acid ? Discuss their 
 properties. 
 
 42. 32.3 cc. of H at 18 C. and 744 mm. are introduced 
 into a eudiometer, 56.8 cc. of () at 20 C. and 745 mm. added. 
 Which gas and how much of it at 21 C. and 745 mm. will be 
 left after the explosion, if the tension of the aqueous vapor 
 produced be taken into account'.' 
 
 43. Show how the composition of water and of hydrogen 
 peroxide illustrate the Law of Multiple Proportions. 
 
 44. Would you use Zn or Fe for making H to fill a large 
 balloon? Why? Would H make; a good illuminating gas ? 
 
 45. Ts water an oxide? an anhvdride?
 
 24 REVIEW QUESTIONS AND PROBLEMS 
 
 46. The density of Cl is nearly thirty-six times that of H. 
 Compare its rate of diffusion with that of H. 
 
 47. If the density of ice is .92, what volume will a liter 
 of water at 4 C. occupy when frozen ? 
 
 48. Give three reasons for considering that water is not 
 an elementary substance. Define the terms " element " and 
 " compound." 
 
 49. How many grams of H can be obtained by treat- 
 ing 30 g. of Zn with sulphuric acid, and what will be the 
 volume at 20 C. and 760 mm. ? 
 
 CHAPTER XI 
 NITROGEN GROUP AND AIR 
 
 1. How can ammonia be made from ammonium chloride ? 
 Write equations to show how ammonium hydroxide reacts 
 with nitric acid and aluminum chloride. 
 
 2. Calculate the volume that 10 1. of air at 25 C. would 
 occupy at C. 
 
 3. Give the name and formula for the common nitrogen 
 :icid. From what is it usually made and how? Illustrate 
 the important chemical properties of the acid by equations 
 for its reactions with both zinc and zinc oxide. 
 
 4. Explain the fact that when strong nitric acid acts on 
 copper, red fumes are evolved. Illustrate your explanation 
 by equations. 
 
 5. Give the formulas for two common oxides of phos- 
 phorus ; also for two common oxides of arsenic. Write 
 the equations for reactions showing the formation of two 
 salts containing phosphorus, and of two salts containing 
 arsenic.
 
 NITRO<;i:X (JROUP AND AIR 25 
 
 6. Show by equations the different effects of concen- 
 trated nitric acid on copper, cuprous oxide, and cupric oxide. 
 
 7. How do arsenic and antimony differ from the true 
 metals ? 
 
 8. Give the reaction equations for the preparation of 
 the following substances : ammonia, nitric acid, nitric oxide, 
 nitrous oxide, phosphorus. 
 
 9. What volume of ammonia gas, at a temperature of 
 20 C. and a pressure of 740 mm. of mercury, can be obtained 
 from 214 g. of sal ammoniac, and how should one proceed 
 to prepare it ? 
 
 10. Name and describe the elements of the nitrogen 
 family ; mention the group to which they belong and state 
 its general characteristics. 
 
 11. Give the sources, preparation, properties, and uses of 
 nitric acid. 
 
 12. Write the formulas of the potassium and ammonium 
 salts of sulphuric and nitric acids ; of nitrogen peroxide. 
 
 13. Why is it impossible to write a chemical formula 
 of air ? Why is a mixture of air with illuminating gas 
 explosive ? 
 
 14. Write the equations for () the neutralization of potas- 
 sium hydroxide and nitric acid; (A) preparation of nitrogen 
 from sodium nitrite and ammonium chloride. 
 
 15. Give, with equation, a jnethod of preparation of 
 ammonia and state the properties of the substance. 
 
 16. Write the formula for primary ammonium phos- 
 phate, secondary potassium phosphate, ammonium sulphate, 
 calcium phosphate, sodium nitrate. 
 
 17. Write the names and formulas of the live oxides of 
 nitrogen. Give a brief statement of the important law 
 illustrated by these compounds.
 
 26 REVIEW QUESTIONS AND PROBLEMS 
 
 18. What are the constituents of the atmosphere : () per- 
 manent ? (b) variable ? 
 
 19. What weight of nitrous oxide will be formed when 
 80 g. of ammonium nitrate is decomposed by heat ? What 
 will be the volume of this nitrous oxide at 745 mm. pressure 
 and a temperature of 18 C. ? 
 
 20. Give the structural formulas of NH 4 CL, NH 4 OH, 
 and (NH 4 ) 2 S0 4 . 
 
 21. The formula of phosphoric acid is H g PO 4 . What is 
 the formula of primary sodium phosphate ? secondary am- 
 monium phosphate ? normal calcium phosphate ? secondary 
 calcium phosphate ? 
 
 22. The specific gravity of ammonia compared to H is 
 8.5. What is its molecular weight? Explain the steps by 
 which this result is reached. 
 
 23. Discuss the preparation of P as to equation and 
 method and describe its allotropic forms. 
 
 24. How is ammonia used in refrigeration ? Describe the 
 methods of preparation and the properties of liquid air. 
 
 25. From what material and by what process may white 
 phosphorus be made ? What are its properties and for what 
 is it used ? How may it be converted into red phosphorus ? 
 
 26. What is white arsenic ? How may arsenic be detected 
 in a case of suspected poisoning ? 
 
 27. Give two reasons for the belief that the nitrogen 
 and the oxygen in the atmosphere are mixed and not 
 combined. 
 
 28. In what great industry is calcium phosphate (normal) 
 employed? To what treatment must it he subjected? How 
 may free phosphorus be prepared ? What is its usual source? 
 
 29. Give the sources, method of preparation, and proper- 
 ties of the element nitrogen.
 
 NITROGEN GROUP AND AIR 27 
 
 30. Give the equation for the reaction that takes place 
 when laughing gas is prepared. Make a sketch of the 
 apparatus used. 
 
 31. Give formulas and names of some compounds of 
 phosphorus, arsenic, and nitrogen, which are analogous in 
 their formulas and chemical behavior. 
 
 32. Which of the constituents of the atmosphere are 
 essential to animal life and which to plant life ? What is 
 returned to the atmosphere by animals and what by plants ? 
 Give two reasons to show that these constituents of the 
 atmosphere are not in chemical combination. 
 
 33. What is the commercial source of ammonia? How is 
 it prepared (equation) and how may it be shown (a) that it 
 has the character of a base, (/>) is lighter than air, (c) and 
 is readily soluble in water ? 
 
 34. When N is prepared from the atmosphere what other 
 element does the gas contain ? Name two different ways in 
 which the salts of nitric acid may be prepared. 
 
 35. Compare the properties of the two common modifica- 
 tions of phosphorus. What is the formula of the product 
 of the combination of phosphorus in oxygen, and what name 
 is given to this compound which indicates its chemical 
 behavior ? 
 
 36. Name two metals which are not readily acted upon 
 by the atmosphere. For what purposes does this property 
 of these metals render them particularly serviceable ? 
 
 37. Name the compounds commonly used as the sources 
 of nitrogen, phosphorus, and potassium in commercial 
 fertilizer. How is the nitrogen of the air made available 
 f<>r plant food? 
 
 38. How could you show the presence of four substances 
 in the air ?
 
 28 REVIEW QUESTIONS AND PROBLEMS 
 
 39. Write the graphic formula of arsenic trioxide. De- 
 scribe its preparation and mention its important properties 
 and uses. 
 
 40. Describe a method of preparing hydrogen arsenide. 
 Give equation. State the ordinary use of hydrogen arsenide. 
 
 41. Explain the instability of nitrogen compounds. De- 
 scribe an experiment illustrating this instability. 
 
 42. Describe a process of extracting the metal arsenic 
 from one of its ores. Mention the physical and chemical 
 properties of arsenic. 
 
 43. Describe in detail Marsh's test for arsenic and write 
 the reaction. 
 
 44. Two compounds have the following composition : 
 () phosphorus 56.36 per cent, oxygen 43.64 per cent; 
 (&) phosphorus 43.65 per cent, oxygen 56.35 per cent. Show 
 whether or not the Law of Multiple Proportion holds. 
 
 45. Give the name and compound formed () when phos- 
 phorus burns in air ; (7/) when the product is treated with 
 water and the solution boiled. Write the equations for both 
 reactions. 
 
 46. Mention four gaseous components of the atmos- 
 phere and tell briefly how you .would demonstrate their 
 presence. 
 
 47. Describe the preparation of ammonium chloride as a 
 by-product in the manufacture of illuminating gas from 
 coal. Give the important uses of ammonium chloride. 
 
 48. Give the composition of ordinary gunpowder. Explain 
 the expansive force of ignited gunpowder and write the 
 reaction that takes place. 
 
 49. Give at least two reasons for the belief that the 
 oxygen and nitrogen of the atmosphere are not in chemical 
 combination.
 
 OXYGEN-SULPHUR GROUP 29 
 
 50. What chemical changes are produced by the action of 
 lightning in the air ? Does atmospheric N differ from that 
 obtained from a compound ? 
 
 51. Name the members of the nitrogen family, tabulate 
 their resemblances and analogous compounds, and show how 
 that relation illustrates the basis of the natural classification 
 of the elements. 
 
 52. When ammonia and air are heated and passed over 
 the catalytic agent (spongy platinum) nitric acid is formed. 
 What does this prove as to the composition of nitric acid ? 
 
 53. What happens to nitric acid when passed through a 
 red-hot tube ? What is the effect of heat upon () potassium 
 nitrate ? (f>) lead nitrate ? (c) ammonium nitrate ? 
 
 CHAPTER XII 
 OXYGEN-SULPHUR GROUP 
 
 1. What volume of oxygen, measured under standard 
 conditions, will be evolved when 198 g. of mercuric oxide 
 are decomposed by heating? What will be the volume of 
 the oxygen at 770 mm. pressure and 27 C. ? 
 
 2. When 2 g. of a certain substance were heated, all 
 the oxygen which the substance contained was given off 
 and the residue weighing 1.97 g. was left. Calculate the 
 percentage of oxygen in the substance. 
 
 3. Describe briefly experiments in the laboratory to illus- 
 trate the effect of heat on sulphur (the air excluded). 
 
 4. State briefly how you could distinguish between 
 
 1. Concentrated and dilute sulphuric acid. 
 
 2. Sodium chloride and sodium sulphate. 
 
 3. Copper sulphate and potassium sulphate.
 
 30 REVIEW QUESTIONS AND PROBLEMS - 
 
 5. State what substances you would use to prepare : 
 (a) S0 2 ; (6)H 2 S; (c) CO ; (rf) CO 2 . 
 
 6. Describe how you would prepare S0 2 in the laboratory. 
 Give its physical and chemical properties. How may it be 
 converted into H 2 S0 4 ? How could you distinguish a solu- 
 tion of sulphurous acid from sulphuric acid ? 
 
 7. Name some of the chemical results which might be 
 expected if the atmosphere were composed entirely of 0. 
 
 8. How is hydrogen sulphide made ? Mention the im- 
 portant physical properties ; the chemical. 
 
 9. What is formed when a solution of sodium hydroxide 
 is saturated with hydrogen sulphide ? 
 
 10. What is the principal product when sulphur burns in 
 the air ? Give two physical properties of the compound 
 and show by equations how it reacts with water and with 
 two different oxidizing solutions. 
 
 11. Write the equations showing the reactions of dilute 
 sulphuric acid with the following substances : (a) sodium 
 sulphide ; (6) potassium carbonate ; (c) ammonium hydroxide ; 
 (d) cupric oxide ; (e) aluminum hydroxide ; (/) lead nitrate ; 
 (ff) barium chloride ; (A) zinc. 
 
 12. Give the formulas for the common oxides of phos- 
 phorus, calcium, copper, and silicon. Which of these oxides 
 unite readily with water ? Give the names and the formulas 
 
 *for the compounds so formed. 
 
 13. Calculate the volume of carbon dioxide at 20 C. and 
 750 mm. pressure that would be produced by burning 200 g. 
 in oxygen. 
 
 14. Write the formulas, and indicate whether basic or 
 acidic, of the oxides of the following elements : aluminum, 
 barium, iron, phosphorus, silicon, sodium, sulphur.
 
 OXYGEN-SULPHUR GROUP 31 
 
 15. Show that the preparation of sulphur dioxide from a 
 sulphite is similar in principle to the preparation of hydrogen 
 sulphide. 
 
 16. Calculate the percentage composition of sulphur- 
 ous anhydride and sulphuric anhydride. Show how these 
 two substances are in harmony with the Law of Multiple 
 Proportions. 
 
 17. How many pounds of sulphur would be necessary in 
 the preparation of 100 Ib. of 90 per cent sulphuric acid ? 
 
 18. Write the names and formulas of the oxides and 
 oxygen acids of selenium and tellurium. 
 
 19. What weight of potassium chlorate is necessary to 
 prepare 200 1. of oxygen at 20 C. and 750 mm., and what is 
 its productive cost at .50 ct. per kilogram ? 
 
 20. How does a mixture of potassium chlorate and man- 
 ganese dioxide act when heated ? What gas is evolved ? 
 Is there interaction, and if not, what is such a process called ? 
 
 21. Distinguish between combustion, decay, oxidation, 
 and putrefaction. 
 
 22. Explain spontaneous combustion and give examples. 
 
 23. Compare the manufacture of sulphur with that of 
 charcoal. 
 
 24. Coal often contains iron pyrites. What sulphur com- 
 pounds do you think would be found in illuminating gas 
 made from such coal ? 
 
 25. How would you distinguish between a sulphide, a sul- 
 phite, and a sulphate ? 
 
 26. How much, both by weight and by volume, is re- 
 quired to burn 100 g. of S containing 12 per cent of incom- 
 bustible impurities ? 
 
 27. Describe the occurrence of sulphur in nature and state 
 the uses to which it is put.
 
 32 REVIEW QUESTIONS AND PROBLEMS 
 
 28. State three ways of preparing S0 2 and tell how it is 
 converted into SO g . 
 
 29. With the aid of Avogadro's hypothesis calculate the 
 volume of oxygen that will be required for the complete 
 combustion of 10 1. of the following gases : (a) acetylene ; 
 (&) methane ; (c) ethane, C 2 H 6 ; (d) ethylene, C 2 H 4 ; (e) CO. 
 What volume of C0 2 will be formed in each case ? 
 
 30. How does ozone differ from oxygen ? How may 
 ozone be prepared ? What are its properties and uses ? 
 Give in full the properties of oxygen. 
 
 31. Give the properties of H 2 S0 4 and describe its prep- 
 aration by the " contact " process. 
 
 32. Give three methods for the preparation of oxygen and 
 explain what relation it bears to respiration and combustion. 
 
 33. How much H 2 S0 4 and zinc would be needed to fill 
 1100 balloons, each of a capacity of 2000 cc., with hydrogen 
 at a pressure of 1000 mm. of mercury ? 
 
 34. Describe (with sketches) two experiments by means 
 of which it may be shown that under certain conditions a 
 gas ordinarily spoken of as a supporter of combustion may 
 become a combustible. 
 
 35. Define oxidation and reduction and give two examples 
 of each. Describe three experiments to illustrate the differ- 
 ence between the properties of oxygen and atmospheric air. 
 
 36. The weight of a liter of O under standard conditions 
 is 1.429 g. What volume will 25 kg. of occupy at a tem- 
 perature of 18 C. and a pressure of 740 mm. ? 
 
 37. What volume of a solution of H 2 S0 4 containing 196 g. 
 of the acid per liter will be required for the exact neutral- 
 ization of 100 cc. of a solution of NaOH containing 40 g. to 
 the liter ? 
 
 38. Give all possible uses of H 2 SO 4 .
 
 OXYGEN-SULPHUR GROUP 33 
 
 39. Write equations showing the result of adding H 2 S0 4 
 to (a) iron ; (7>) quicklime ; (c) a solution of barium chloride. 
 What is the chemical change which takes place when 
 H a S0 4 is added to sugar? 
 
 40. Under what conditions is native sulphur usually 
 found ? Name two classes of sulphur compounds which 
 occur in nature. 
 
 41. How may S0 2 be prepared by (a) an oxidizing proc- 
 ess ? (&) by reduction ? 
 
 42. How many grams of copper sulphide can be formed 
 by burning 2 g. of copper in sulphur vapor ? 
 
 43. Explain the chemical difference in the bleaching 
 action of SO 2 and Cl. 
 
 44. Describe () the principal sources of sulphur in nature. 
 (l>) State one method of preparation, (c) Mention allotropic 
 forms. 
 
 45. Explain why the gaseous product produced by the 
 action of H 2 SO 4 with copper differs from that usually pro- 
 duced by the action of an acid with a metal. 
 
 46. Give the proportions of in normal air by weight 
 and by volume and describe a laboratory experiment to 
 show how each of these proportions are determined. 
 
 47. Describe an experiment showing the value of H 2 S as 
 a reducing agent. State the property of H 2 S to which its 
 value as a reducing agent is due. 
 
 48. Berzelius converted 10.000 g. of lead into 14.642 g. 
 of lead sulphate (PbSO 4 ). The atomic weights of lead and of 
 oxygen are 206.91 and 16.00. Calculate the atomic weights 
 of sulphur. 
 
 49. Is the equation for the preparation of hydrosulphuric 
 acid a reversible one ? As ordinarily carried out, does it com- 
 plete itself ? Does dry hydrosulphuric acid react with litmus ?
 
 34 REVIEW QUESTIONS AND PROBLEMS 
 
 60. In what respects is sulphurous acid like carbonic acid ? 
 
 51. How does a mixture of chlorate and manganese 
 dioxide act when heated ? Calculate the volume under 
 standard conditions and also the weight of the gas pro- 
 duced if 245 g. of chlorate are used. 
 
 52. Describe a method of preparing oxygen, describe its 
 properties, and relate the history of its discovery. 
 
 53. Describe the lead-chamber process for the manufacture 
 of H 2 S0 4 . 
 
 54. Define combustion and kindling temperature. Give an 
 account of the discovery of oxygen and of the effect which 
 the study of its properties had upon the development of the 
 science of chemistry. 
 
 CHAPTER XIII 
 CARBON, SILICON, TIN, LEAD GROUP 
 
 1. Compare the composition, manner of formation, and 
 properties of the oxides of carbon, silicon, tin, and lead. 
 
 2. How do you account for a weak acid such as H 2 C0 3 
 being able to decompose such stable compounds as the sili- 
 cates, as illustrated by the weathering of rocks ? 
 
 3. A certain ore has 90 per cent galena. How much 
 pure lead can be obtained from a ton of the ore ? 
 
 4. If white lead were mixed with barium sulphate, how 
 could you detect the adulteration ? 
 
 5. What are hydrocarbons and where are they found ? 
 Mention three hydrocarbons present in illuminating gas. 
 
 6. Why does the air of a tightly closed room in which 
 lamps are burning become unfit to breathe ? What is the 
 explanation of the explosions which often occur in houses 
 when illuminating gas has been escaping ?
 
 CARBON, SILICON, TIN, LEAD GROUP 35 
 
 7. What is the purpose in using baking soda in dough ? 
 Why does a lamp burn better with the chimney on than off ? 
 
 8. Describe the manufacture of white lead, giving equa- 
 tions and uses. 
 
 9. Discuss combustion, the nature of a flame, and the 
 factors which cause and modify the luminosity of a flame. 
 
 10. Describe fully the oxides of carbon and the ways 
 in which they are formed and prepared. 
 
 11. Point out the chemical similarity between carbon and 
 silicon. 
 
 12. Give (a) the equation for the combustion of carbon 
 monoxide in oxygen, (i) What will be the relative volumes 
 of the gases taking part in the reaction ? (c) What will be the 
 relative weights of the gases ? (d) If 56 g. of carbon monoxide 
 are used, what will be the volumes of oxygen required under 
 standard conditions ? 
 
 13. Calculate the volume occupied by 10 g. of carbon 
 dioxide at 27 C. and 38 cm. pressure, assuming that 1 g. of 
 C0 2 at C. and 76 cm. occupies .509 1. 
 
 14. Calculate the weight of sodium hydroxide that would 
 react with 22.4 1. of C0 2 under normal conditions of tem- 
 perature and pressure, sodium hydroxide to be in excess. 
 
 15. State from personal experience how C0 2 was pre- 
 pared in the laboratory, and write the reaction involved. 
 State two properties of CO 2 which were ascertained by 
 experiment. How may it be shown that C0 2 is one of the 
 products of respiration ? 
 
 16. What do you consider the most important compound 
 of (a) carbon ? (ft) silicon ? (c) tin ? (d) lead ? Why ? 
 
 17. How does the total weight of the products of com- 
 bustion of a candle compare with the total weight of the 
 materials taking part in the combustion ? Name and state 
 the law which this illustrates.
 
 36 REVIEW QUESTIONS AND PROBLEMS 
 
 18. State a chemical method of distinguishing between 
 CO and C0 2 and describe a method by which each may be 
 converted into the other. 
 
 19. Name an important ore of lead. How would you 
 proceed to get metallic lead into solution ? Give the formula 
 of the resulting compounds of lead. 
 
 20. Name two natural and two artificial modifications of 
 the element carbon. What are the chief products resulting 
 from the heating of soft coal without access of air ? How 
 does coal gas differ chemically from water gas ? Under what 
 conditions does a combustible substance burn with a flame ? 
 Name two purposes for which graphite is commonly used. 
 
 21. Name the substances used in the manufacture of 
 glass. How does the composition of hard glass differ from 
 that of soft glass ? 
 
 22. How is water gas made ? What gases does it contain ? 
 Why is it carburetted (enriched) ? To what constituent is 
 the poisonous character chiefly due ? 
 
 23. Give the chemical name and the mineralogical name 
 of one important ore of lead. Describe briefly the mode of 
 extracting the metal, name two practical uses to which it is 
 put, and state what property renders it particularly suited 
 to each purpose named. What metals are components of 
 solder and brass ? 
 
 24. Discuss the chemical changes which take place in a 
 furnace fire, as follows : 
 
 1. What substances cause the blue flame at the surface 
 
 of the coal and how is it formed ? 
 
 2. State and give reasons for the effects of admitting 
 
 air (a) to the top of the fire ; (b) to the bottom. 
 
 3. How does anthracite coal differ from bituminous 
 
 in appearance and chemical quality ?
 
 CARBON, SILICON, TIN, LEAD GROUP 37 
 
 25. Draw a vertical section (diagram of a candle flame), 
 showing its structure. Indicate on the diagram the part of 
 the flame having (a) greatest luminosity ; (6) greatest heat. 
 
 26. Find the weight of each of the products of combustion 
 when 78 g. of acetylene are burned. 
 
 27. Write in order the chemical name and the formula 
 of each of five members of the marsh-gas series. 
 
 28. Describe the process of fractional distillation of 
 petroleum. Mention three useful products derived from it, 
 with formulas. 
 
 29. Distinguish as to chemical composition and properties 
 between fire damp and choke damp and explain why each 
 is dangerous in mines. 
 
 30. Describe in detail a process of manufacturing lead 
 carbonate on a commercial scale. State the principal use 
 of it. 
 
 31. Give the construction of the Davy safety lamp and 
 describe a laboratory experiment to illustrate the principle 
 on which its safety depends. 
 
 32. Describe the construction and explain the operation 
 of a Bunsen burner. 
 
 33. Compare the action of carbon and chlorine as disin- 
 fecting agents. 
 
 34. Give the theory to account for the formation of 
 () petroleum ; (6) natural gas. 
 
 35. Describe a method of preparing acetylene and state 
 its physical and chemical properties. 
 
 36. (") Explain the formation of marsh gas in nature. 
 (6) Distinguish between carbohydrate and hydrocarbon, 
 (c) Mention two groups of carbohydrates. 
 
 37. Describe the manufacture of glass and distinguish 
 between window glass and green bottle glass.
 
 38 REVIEW QUESTIONS AND PROBLEMS 
 
 38. Mention () the principal products obtained from the 
 destructive distillation of bituminous coal ; (b) two great 
 natural sources of C0 2 . (c) Explain why the percentage of 
 C0 2 in the air remains nearly uniform. 
 
 39. Describe the preparation and give the properties and 
 uses of (a) lampblack ; (6) coke, (c) What is the source of 
 gas carbon and its use ? 
 
 40. If a candle consists of 87 per cent carbon and of 
 13 per cent hydrogen, what weights of C0 2 and of H 2 will 
 be formed when 50 g. of the candle burn ? 
 
 41. What weight of CO will be formed upon treating 
 25 g. of oxalic acid with concentrated sulphuric acid ? 
 
 42. Name the natural and artificial forms of free carbon 
 and state how they differ from one another. 
 
 43. What volume of C0 2 would be formed respectively 
 by the complete combustion of (ft) 12 1. of acetylene ? (i) 7 1. 
 of propane (CJIJ ? (c) 75 cc. of CO? (d) 2.5 1. of methane? 
 (e) 4 1. of ethylene (C 2 H 4 ) ? 
 
 44. Through what cycle does carbon pass in animal and 
 vegetable life ? 
 
 45. How may coke be converted into graphite ? What is 
 animal charcoal ? For what purpose is it used ? 
 
 46. Describe () the process employed in the manufacture 
 of carborundum. Of what practical use is the substance ? 
 (i) In what forms does silica occur in nature ? In what 
 industry are silica and the silicates of great importance ? 
 
 47. Calculate the weight of calcium carbonate that could 
 be precipitated by the action of 10 1. of C0 2 (measured under 
 745 mm. pressure at 21 C.) upon a solution of Ca(OH) 2 . 
 
 48. Name three allotropic forms of carbon and show how 
 their chemical identity may be proved. By what reaction 
 may C0 2 be distinguished from CO ?
 
 CARBON, SILICON, TIN, LEAD GROUP 39 
 
 49. What is allotropy and how is it illustrated and 
 accounted for in the case of the element carton ? 
 
 50. Name three important substances obtained by the 
 destructive distillation of (W) wood ; (/>) soft coal. 
 
 51. What is an alloy? Mention an alloy and state three 
 ways in which its properties differ from those of its constit- 
 uents. Name an alloy of lead and of tin. 
 
 52. Make a comparison between () carbon and silicon as 
 to compounds formed ; (/) between carbon, oxygen, sulphur, 
 and phosphorus as to allotropic forms. 
 
 53. Suggest a probable way that natural gas has been 
 formed. 
 
 34. Coal frequently contains sulphide of iron. What 
 sulphur compounds are likely to be formed when gas is 
 made from such coal, and what would be the method for 
 the removal of these compounds ? 
 
 55. Could a solution of NaOH be substituted for the 
 solution of Ca(OH) 2 in testing for CO 2 ? 
 
 56. How would you distinguish between C0 2 , and O, H, 
 N, and N a O ? 
 
 57. How would you distinguish between carbonates and 
 sulphites ? 
 
 58. Write the equations for the preparation of MgCO 8 , 
 BaCO 8 , K a C0 8 , Na 2 CO 8 , and CaC0 8 . 
 
 59. How would you detect the presence of lead in tinfoil? 
 
 60. Since stannous chloride reduces gold chloride, give 
 the equation for extracting gold. 
 
 61. What sulphates other than lead are insoluble ? 
 
 62. (o.) In what respect is silica similar to tin and lead ? 
 (b) Given one ton of cassiterite, how much tin could be 
 obtained by its reduction ?
 
 40 REVIEW QUESTIONS AND PROBLEMS 
 
 63. How can you determine whether a given crystal is 
 quartz or calc-spar ? 
 
 64. Dumas, in 1859, added to a solution containing 4.5049 
 of stannous chloride an excess of a solution of silver nitrate 
 and found that the precipitate of silver chloride formed con- 
 tained 7.481 g. of silver. What is the atomic weight of tin, 
 if the atomic weights of Cl and Ag are 35.43 and 107.94 
 respectively ? 
 
 65. Explain the principle of the chemical fire extin- 
 guisher, state what materials are used, and give the 
 equation. 
 
 66. Give the most important use of silicon dioxide and 
 explain why silicon is not found free in nature. 
 
 67. What is water glass ? How is it produced and what 
 are its uses ? 
 
 68. Calculate the percentage of C0 2 and CO and restate 
 the percentages in a form which illustrates the Law of 
 Multiple Proportions. 
 
 69. A gaseous hydrocarbon contains 85.71 per cent of 
 carbon ; its density referred to oxygen is .875. What is its 
 simplest formula and its molecular formula ? 
 
 70. Write the formulas for the following compounds : 
 silicon iodide, hydrogen silicide, silicon sulphide, carbon 
 silicide. 
 
 71. Write the equations for the preparation of silicic acid ; 
 carbonic acid. Write the formulas of the following: k-ud 
 sodium acetate, stannous bromide, thorium nitrate, cerium 
 sulphate, lead chromate, lead sulphide, lead tetroxide, stannic 
 chloride, stannous sulphide, stannic oxide. 
 
 72. Thorium is much like what other newly discovered 
 element ? 
 
 73. How is animal charcoal obtained?
 
 THE HALOGENS 41 
 
 74. Describe the manufacture of shot, touching on (a) sub- 
 stances used; (6) processes used. Explain each process 
 mentioned. Why is arsenic used in the manufacture of shot? 
 
 75. Give a laboratory method of preparing each of the 
 oxides of carbon. Compare the chemical properties of these 
 oxides and state the effects of each on animal life. Explain 
 the formation of each in a coal fire. 
 
 CHAPTER XIV 
 THE HALOGENS 
 
 1. How may chlorine, bromine, and iodine be prepared ? 
 Write the equation representing the reaction involved in 
 each case. Why are these elements grouped together? 
 
 2. Describe another method for the preparation of chlo- 
 rine and write the equation for the reaction involved. 
 
 3. Why is moisture necessary to the bleaching action of 
 Cl? What is formed when hydrogen burns in chlorine and 
 how may the product be distinguished from chlorine ? 
 
 4. () How may chlorine be prepared ? State its prop- 
 erties. () What elements constitute the halogen group and 
 why are they grouped together ? 
 
 5. Give the properties of Cl and state what is formed 
 when it is passed into a hot concentrated solution of 
 potassium hydroxide. 
 
 6. What weight of chlorine will be set free when a so- 
 lution containing 75 g. of sodium chloride is electrolyzed, 
 and what will be the volume of the chlorine gas thus made 
 at a temperature of 20 C. and a pressure of 740 mm.? 
 
 7. How many liters of chlorine can be obtained from 
 . of common salt?
 
 42 REVIEW QUESTIONS AND PROBLEMS 
 
 8. Name the principal characteristics of each of the 
 halogens in the free state. Why are they grouped together ? 
 Describe a method for the laboratory preparation of free 
 bromine and write the reaction. 
 
 9. What is the chief source of iodine in commerce ? 
 What are its properties ? How may its presence be detected ? 
 
 10. Calculate the approximate weights in grams of 1 1. 
 of each of the following gases : C1 2 , HC1, HBr, HF. 
 
 11. What weight of chlorine can be prepared from 78 g. 
 of rock salt containing 99 per cent NaCl ? How much 
 manganese dioxide and sulphuric acid would be required to 
 carry out the reaction ? What volume would the chlorine 
 occupy under standard conditions ? What volume of hy- 
 drochloric acid would be formed ? 
 
 12. Write the equation for preparing hydrofluoric acid. 
 Describe and explain the process of etching glass. State two 
 methods of identifying iodine. 
 
 13. Describe and explain the action which occurs when 
 chlorine water is added to a solution of potassium iodide 
 containing starch. 
 
 14. If 100 g. of magnesium are completely dissolved in 
 hydrochloric acid, what volume will be occupied at 18C. 
 and 760 mm. by the gas evolved ? If this gas is then burned 
 in oxygen, what substance will lie produced and how much ? 
 
 15. If a quantity of a gas measures 493 1. at 784 mm. and 
 20 C., what will be its volume under standard conditions ? 
 Supposing the gas to be hydrogen chloride, calculate its 
 weight. What weights of materials would be required to 
 prepare it ? 
 
 16. What occurs when Cl is passed into () a cold and 
 dilute solution of potassium hydroxide, and (ft) into a hot 
 and concentrated solution ?
 
 THE HALOGENS 43 
 
 17. Mention some important chlorides formed in nature ; 
 some that are artificially produced. 
 
 18. Describe in detail the process of bleaching, giving 
 the reaction involved. 
 
 19. What is chlorinization ? What are the tests for 
 chlorine and the chlorides ? 
 
 20. Give the reaction involved in the process of disin- 
 fecting with Cl. 
 
 21. Name the acids of Cl and write and name the zinc 
 salt of each. 
 
 22. Compare the elements of the halogen group as to 
 (a) state, (6) color, (c) weight, (d) chemical activity. 
 
 23. Calculate the volume of hydrochloric acid solution, 
 density 1.1 and 20 per cent pure acid by weight, that would 
 be required, to neutralize 50 g. of Ca(OH) 2 . 
 
 24. How may Cl and HC1 gas be obtained, starting from 
 common salt in each case ? In what chemical way may 
 these two substances be distinguished from each other ? 
 
 25. Give reasons why the halogens are regarded as 
 members of a natural group of elements. 
 
 26. How do you ascertain the properties of HC1 and how, 
 in addition, could you show that this compound contains 
 (a) hydrogen ? (6) chlorine ? 
 
 27. Describe the preparation of HC1 as a by-product in 
 the manufacture of sodium carbonate. Give its physical 
 and chemical properties. 
 
 28. Describe in detail an experiment illustrating the 
 bleaching properties of Cl. 
 
 29. Give the important physical and chemical properties 
 of iodine. Mention one source and two uses of iodine.
 
 44 REVIEW QUESTIONS AND PROBLEMS 
 
 30. Write equations for the preparation of potassium 
 bromide by three different methods. 
 
 31. If a solution contains potassium bromide and potas- 
 sium chloride, how would you show the presence of the 
 halogens ? 
 
 32. How do you account for the fact that solutions of 
 hydriodic acid become dark on standing some time ? 
 
 33. Write the equations for the reactions of bromine with 
 zinc, water, antimony, and hydrogen. 
 
 34. How many liters of N may be obtained by the inter- 
 action of Cl with NH 8 ? 
 
 35. If the weight of 1 1. of HC1 gas is 1.735 g., what is 
 the elemental weight of chlorine ? 
 
 36. How many grams of NaCl are required to prepare 
 half a kilogram of hydrogen chloride ? 
 
 37. The analysis of a certain compound gave the following 
 results : 
 
 1. C = 12.00 per cent 2. 11.69 per cent 3. 11.83 per cent 
 
 H = 3.98 per cent 4.02 per cent 4.00 per cent 
 
 N = 6.77 per cent 6.80 per cent 6.78 per cent 
 
 Br = 77.56 per cent 77.61 per cent 77.64 per cent 
 
 What was the formula ? 
 
 38. A saturated solution of Cl when exposed to sun- 
 light yielded 20 cc. of a gas. How would you establish 
 the identity of the gas and how much Cl was required to 
 produce it ? 
 
 39. CaO + 2 NH 4 C1 = 2 NH 8 + H 2 -f CaCl 2 . Given 56 
 grains of lime, how many cu. ft. of ammonia at C. and 
 15 Ib. pressure would result from the above reaction ? 
 
 40. Write the formulas for the following compounds : 
 magnesium iodide, mercuric bromide, silicon fluoride, ferrous 
 bromide, ferric chloride, lead iodide.
 
 THE ALKALINE-EARTH METALS 45 
 
 CHAPTER XV 
 THE ALKALINE-EARTH METALS 
 
 1. What reaction takes place when magnesium flash- 
 light powder is set on fire ? 
 
 2. The gas density of mercury is 100. What is the for- 
 mula for the molecule ? Why is nitric acid a better solvent 
 for Hg than hydrochloric ? 
 
 3. What is the approximate specific heat of cadmium, 
 accepting 112 as its atomic weight ? 
 
 4. How much Hg is formed by decomposing 500 g. of 
 cinnabar ? 
 
 5. Write the formulas for the following compounds : 
 mercuric sulphate, mercuric iodide, mercurous bromide, cad- 
 mium sulphate, cadmium iodide, zinc iodide, zinc acetate, 
 potassium zincate, magnesium fluoride, magnesium phos- 
 phate, ammonium magnesium phosphate, magnesium iodide. 
 
 6. What properties have the metals of the magnesium 
 family in common with the alkali metals ? with the alkaline- 
 earth metals ? 
 
 7. Distinguish between magnesium chloride and magne- 
 sium sulphate ; between Epsom salts and Glauber salts. 
 
 8. What hydroxide studied, other than zinc hydroxide, 
 has both acid and basic properties ? 
 
 9. What property of Mg is made use of in the isolation 
 of argon ? 
 
 10. Erdman and Marchand, in 1844, obtained 352.4079 g. 
 of mercury by heating 380.5744 g. of mercuric oxide. What 
 is the atomic weight of mercury ? 
 
 11. How may quicklime be prepared? What chemical 
 change takes place in the drying of ordinary mortar ?
 
 46 REVIEW QUESTIONS AND PROBLEMS 
 
 What substances ordinarily cause temporary and perma- 
 nent hardness in water ? Write the equation representing 
 the reaction involved in the removal of temporary hardness 
 by boiling. 
 
 12. Name four forms in which calcium carbonate occurs 
 in nature. How may quicklime be prepared ? What happens 
 when water is added to quicklime ? What is plaster of 
 Paris and from what is it made? 
 
 13. What is meant by radioactivity ? What is the pres- 
 ent source of radium ? What are the effects of the rays 
 given off from radium ? 
 
 14. Explain in detail how such elements as sodium and 
 calcium can be detected with the aid of the spectroscope. 
 
 15. The most important ore containing mercury is cin- 
 nabar (HgS). Where is it found ? How is the mercury 
 extracted from it ? What are the commercial names of 
 inercurous chloride and mercuric chloride and how do the 
 two differ from each other in chemical properties ? 
 
 16. 'xiow many grams of quicklime and how many liters 
 of C0 2 would be formed by heating 1 kg. of limestone ? 
 
 17. What substances ordinarily cause temporary and 
 permanent hardness of water respectively ? Explain the 
 chemistry involved in the removal of temporary hardness 
 and give the equation expressing the reaction. 
 
 18. What weight of Zn would be required for the pro- 
 duction of sufficient hydrogen, at 21 C. and 745 mm. pressure, 
 to fill a balloon having a capacity of 100 cc. ? 
 
 19. What weight of calcium carbonate is required to neu- 
 tralize 400 cc. of hydrochloric acid solution which contains 
 100 g. of the pure substance ? 
 
 20. A flask has a capacity of 15 1. The prevailing temper- 
 ature is 18 C. and the atmospheric pressure is 752mm.;
 
 THE ALKALINE-EARTH METALS 47 
 
 what weight of Zn, reacting with H 2 S0 4 , would be needed to 
 fill the flask with hydrogen under the prevailing conditions ? 
 
 21. How is lime prepared? What is the action of the 
 atmosphere upon it ? What is mortar ? How is it prepared 
 and what chemical changes occur when it hardens ? 
 
 22. What is the specific heat of cadmium if its atomic 
 weight is 112 ? 
 
 23. How much () calomel can be obtained from 200 g. of 
 mercurous sulphate ? (>) how much corrosive sublimate ? 
 
 24. Hauer, in 1868, found by heating 64.2051 g. of cad- 
 mium sulphate (CdS0 4 ) that 44.4491 g. of cadmium sulphide 
 were left. Taking the atomic weights of oxygen and sulphur 
 as 16.00 and 32.06 respectively, calculate the atomic weight 
 of cadmium. 
 
 25. Why is normal calcium phosphate converted into 
 superphosphate in the manufacture of fertilizers ? 
 
 26. How is a limekiln built, and why is the production of 
 lime hastened by blowing air or steam into the kiln ? 
 
 27. What is the test for a magnesium compounu ? for 
 zinc ? for strontium ? for cadmium ? 
 
 28. Name two alloys of zinc and state what each contains. 
 
 29. How is zinc obtained from its ores ? Mention two 
 ways to prepare zinc sulphide. 
 
 30. Name a compound of Zn used as a base for paint. Why 
 is a zinc paint especially valuable in chemical laboratories ? 
 
 31. What special name is given to the alloys of mercury ? 
 
 32. How would you test for a soluble salt of Hg ? Calcu- 
 late the percentage composition of the two chlorides of Hg. 
 
 33. Give a method for making zinc chloride from the 
 sulphate, with equations. Write equations for the reactions 
 of a dilute solution of () zinc bromide, with silver nitrate ; 
 (/>) sodium hydroxide ; (c) chlorine ; (it) ammonium sulphide.
 
 48 REVIEW QUESTIONS AND PROBLEMS 
 
 34. Write equations showing four methods by which the 
 salt, zinc sulphate, could be made. 
 
 35. Describe the process of converting (a) limestone into 
 quicklime ; (6) quicklime into slaked lime. Write the re- 
 action .in each case. 
 
 36. Mention three ores of zinc. Describe the ordinary 
 method of extracting zinc from the ores mentioned. Write 
 the reaction. 
 
 37. Give the physical and chemical properties of Zn and 
 describe the process of galvanizing and explain its use. 
 
 38. Show by equation how the following compounds of 
 zinc may be obtained from metallic zinc : the oxide, chloride, 
 nitrate, carbonate, sulphate, sulphide, hydroxide. 
 
 39. Write the equation for the reaction between barium 
 chloride and sulphuric acid in (a) the ordinary chemical 
 form and (6) the ionic form. 
 
 40. If 64.2508 g. of cadmium sulphate yield 44.4491 g. of 
 cadmium sulphide, what is the atomic weight of cadmium ? 
 
 41. How is Zn obtained in a commercial scale from zinc 
 ore ? Why is it used for galvanizing iron wire ? What com- 
 pound of Zn is used in the manufacture of paint? Define 
 the terms "alloy" and "amalgam" and give an example 
 of each. 
 
 42. What is meant by radioactivity ? What are alpha, 
 and beta particles? Are they electrons? Does radioactivity 
 differ from other chemical reactions ? 
 
 43. Describe, writing the equations to express the reac- 
 tions in each case, the chemical changes that take place in 
 the calcium compound from the time it leaves the quarry as 
 limestone till it hardens into plaster on the wall. 
 
 44. Calculate the simplest formula for a compound having 
 the percentage compositions Ca = 40, C = 12, O = 48.
 
 THE ALKALI METALS 49 
 
 CHAPTER XVI 
 THE ALKALI METALS 
 
 1. Write the formulas of the following compounds by 
 applying the principles of valence : sodium fluoride, sodium 
 phosphate, sodium chlorite, sodium acetate, potassium man- 
 ganate, acid potassium sulphite, lithium carbonate, lithium 
 chloride, lithium phosphate, potassium nitrate, sodium sul- 
 phate. 
 
 2. How much sodium will 4 kg. of sodium carbonate 
 yield if heated with carbon ? 
 
 3. Describe the preparation of potassium hydroxide from 
 potassium carbonate and write the reaction. Give the phys- 
 ical and chemical properties of potassium hydroxide. 
 
 4. Describe the Solway process of manufacturing sodium 
 carbonate. Write the reactions. 
 
 5. (a) Mention two alkali metals and give the formulas 
 for their hydroxides, carbonates, and sulphates ; (b) point 
 out how these compounds differ in solubility from the cor- 
 responding compounds of the alkali-earth metals. 
 
 6. What is formed when a solution of sodium hydroxide 
 is saturated with hydrogen sulphide ? 
 
 7. Give a brief description of making soda from common 
 salt and making caustic soda from soda. 
 
 8. Describe the manufacture of caustic soda from rock 
 salt according to the electrolytic process. 
 
 9. Describe the Le Blanc process of manufacturing 
 Na 2 S0 4 . 
 
 10. Give a complete description of the action of the metal 
 sodium upon water. Give the properties of the products of 
 the action. Give a similar account of potassium.
 
 50 REVIEW QUESTIONS AND PROBLEMS 
 
 11. How many grams of sodium will be needed to com- 
 bine exactly with a quantity of chlorine which at 18 C. and 
 740 mm. occupied a volume of 200 cc. ? What will be the 
 weight of the resulting salt? 
 
 12. Describe the commercial electrolytic method of ob- 
 taining the metal sodium and write the reaction. 
 
 13. Write the equations for the 
 
 1. Action of dilute sodium hydroxide on chlorine. 
 
 2. Nitric acid neutralized by potassium hydroxide. 
 
 14. Name the potassium salt and give the formula for 
 each of these acids: HC1, HC10, HC10 2 , HC10 3 , HC10 4 , 
 HN0 2 , HN0 8 , H 2 S0 4 , HBr, H g AsO 4 , HF. 
 
 15. What weight of NaOH must be dissolved in 1 1. 
 of water to yield a solution of such strength that 10 cc. of 
 it will exactly neutralize 5 cc. of a solution of HNO g that 
 contains 126 g. of the acid in 11.? 
 
 16. Describe in detail what happens when a solution of 
 sodium sulphate is electrolyzed. How may the direction 
 of the current be determined ? 
 
 17. How many kilograms of crystallized sodium carbonate 
 (Na 2 C0 8 10 H 2 0) could be obtained from 1000 kg. of salt ? 
 
 18. What weight of HNO g would be required to exactly 
 neutralize 30 g. of NaOH, and what weight of sodium nitrate 
 would be formed ? 
 
 19. Write the equations 
 
 1. Potassium and sulphuric acid. 
 
 2. Calcium hydroxide and ammonium hydroxide. 
 
 3. Sodium hydroxide and phosphoric acid. 
 
 4. Ferric chloride and ammonium hydroxide. 
 
 20. Give the formulas for three important compounds of 
 sodium. How are these compounds obtained and to what 
 use are they put ?
 
 THE ALKALI METALS 51 
 
 21. Write the formulas for the following compounds and 
 name the acids of which they are salts: sodium hypochlo- 
 rite, sodium chlorite, sodium chlorate, sodium perchlorate, 
 sodium chloride. 
 
 22. What is water glass ? Give two uses to which the 
 substances may be put. 
 
 23. How many grams of potassium hydroxide are con- 
 tained in 11. of a solution that 6.4 cc. will completely 
 neutralize 9.6 cc. of normal solution of HC1 ? 
 
 24. How much sodic chloride may be obtained from 10 g. 
 of crystallized sodic carbonate ? 
 
 25. To what extent does the composition of a pure chem- 
 ical compound vary ? Take as an example pure 'sodium 
 chloride from various sources and mention other examples 
 if possible. 
 
 26. Discuss the use of potassium compounds as a fertilizer. 
 State the co'mmon form and its formula. 
 
 27. Name two compounds of sodium which are commonly 
 employed in the household and give the use of each. 
 
 28. What are constituents of common gunpowder ? What 
 is the formula for caustic potash ? 
 
 29. How may Na 2 CO g 10 H 2 be converted into NaOH, 
 and how may metallic sodium be made from NaOH ? Give 
 reactions. 
 
 30. Give the tests for sodium ; for potassium ; for lithium. 
 
 31. Explain the formation of potassium nitrate by 
 nitrification. 
 
 32. In what location are sodium, potassium, and lithium 
 produced in nature ? 
 
 33. Give the chemical difference between sodium carbon- 
 ate and sodium bicarbonate. What are their common names 
 and their uses ?
 
 52 REVIEW QUESTIONS AND PROBLEMS 
 
 34. If a gram of gunpowder produces 300 cc. of gas at 
 O C., what will its volume be at 2000 C. ? 
 
 35. Give the important compounds of lithium ; their 
 properties and uses. Give the properties of lithium. 
 
 36. Name all the members of this group and compare 
 them as to common characteristics. 
 
 37. Which of these gases would you dry with solid caustic 
 potash : oxygen, carbon dioxide, ammonia, carbon monoxide ? 
 
 38. How would you prove the presence of potassium in 
 plants ? 
 
 39. Distinguish by analysis between sodium chloride and 
 ammonium chloride. 
 
 40. How would you distinguish between KF, KI, Kl>r, 
 KC1? 
 
 41. Why does KHS0 4 react acidic, while NaHCO 8 reacts 
 alkaline ? 
 
 42. Sodium nitrate is used in the preparation of H]^() 3 . 
 Why not potassium nitrate ? 
 
 43. How could you prove that the water in crystals of 
 NaCl is not water of crystallization ? 
 
 CHAPTER XVII 
 ALUMINUM-BORON GROUP 
 
 1. How is aluminum obtained ? Is the method of elec- 
 trolysis used in decomposing the more stable or the less 
 stable compounds ? 
 
 2. What care must be taken of kitchen utensils made of 
 aluminum ? 
 
 3. (a) How could you prove that alum contains alumi- 
 num ? (U) What are the properties of aluminum ?
 
 ALUMINUM-BORON GROUP 53 
 
 4. Explain why alum turns litmus red and borax turns 
 litmus blue. 
 
 5. What is the per cent of aluminum in (a) cryolite 
 (Na 8 AlF 6 )? (ft) in turquoise (Al^O, H 8 A1 2 6 2 H 2 O)? 
 
 6. Write the formulas for aluminum sulphide, aluminum 
 phosphate, aluminum acetate, potassium aluminate. 
 
 7. Write the equation to show how aluminum hydroxide 
 can play the part of a base ; of an acid. 
 
 8. What compound of aluminum is formed when a solu- 
 tion of calcium carbonate reacts with a solution of aluminum 
 sulphate ? 
 
 9. Describe briefly the commercial process for the prepa- 
 ration of aluminum from aluminum oxide. 
 
 10. Give the properties of metallic aluminum and the 
 name and formula of an important salt. 
 
 11. How many grams of aluminum can be obtained from 
 200 kg. of bauxite (A1 2 8 - 2 H 2 0) ? 
 
 12. Describe the reaction that takes place between metallic 
 aluminum and ferric oxide when a mixture is ignited. Give 
 the equation and state what practical applications are made 
 of the reaction. 
 
 13. Describe in detail the Goldschmidt process for weld- 
 ing iron, giving the equation expressing the reaction. 
 
 14. () Complete and balance the following: 
 
 1. Al a (S0 4 ) 8 + KOH= 3. A1(OH) 8 + HC1 = 
 
 2. Al (OH), + KOH = 4. AgN0 8 + KBr = 
 
 (i) Is aluminum hydroxide to be regarded as an acid or 
 as a base? 
 
 15. What is the composition of the mixture termed 
 " thermit " ? What is the chemical action that takes place 
 between these components ? What practical use is made of 
 thermit ?
 
 54 REVIEW QUESTIONS AND PROBLEMS 
 
 16. Explain the use of aluminum sulphate in the purifi- 
 cation of water. 
 
 17. Having solutions of magnesium sulphate, cadmium 
 chloride, and aluminum sulphate, how would you test for 
 the metallic ions ? What is a mordant ? 
 
 18. What are the products obtained by heating sodium 
 sulphate with boracic acid? 
 
 19. How many grams of C0 2 are evolved when 200 g. of 
 borax are made by the interaction of boric acid and Na 2 CO 3 ? 
 
 20. Which contains the larger percentage of boron boric 
 acid, boracic acid/ or boron trioxide ? 
 
 21. What is the formula for ferric ammonium alum and 
 what are its properties and uses ? 
 
 22. Terreil, in 1879, found that 0.0455 g. of H was 
 evolved when 0.410 g. of aluminum was dissolved in an 
 acid. What is the atomic weight of aluminum calculated 
 from this experiment ? 
 
 23. What hydroxides other than aluminum hydroxide 
 have both acid and basic properties ? 
 
 24. Write the equations for the preparation of aluminum 
 hydroxide and aluminum sulphate. 
 
 25. Write the general formula of an alum, letting M 
 represent the atom of the alkali metal and X the atom of 
 the trivalent metal. 
 
 26. In what respect does aluminum oxide differ from cal- 
 cium oxide in properties ? 
 
 27. Explain the use of borax for the " softening of water" ; 
 the use of it in the " borax bead's " test. 
 
 28. How could Al, NH 4 , and S0 4 be recognized in an alum 
 solution ? Illustrate with equations. 
 
 29. What volume of at 15 C. and 760 mm. is needed to 
 change 8 Ib. of aluminum into aluminum oxide (A1 2 O 8 ) ?
 
 IRON, NICKEL, COBALT, PLATINUM GROUP 55 
 
 CHAPTER XVIII 
 IRON, NICKEL, COBALT, PLATINUM GROUP 
 
 1. Does iron occur free in nature ? Give the reason. 
 
 2. Name and compare the three varieties of iron. Why 
 should these not be regarded as allotropic forms ? 
 
 3. There are two metallurgical processes. Iron illustrates 
 one and sodium the other. Describe each process. 
 
 4. Describe the manufacture of iron in the blast furnace. 
 
 5. Describe in detail the manufacture of pig iron from 
 iron ore. 
 
 6. Give the tests for iron. 
 
 7. Name at least three iron ores. Describe the manu- 
 facture of cast iron. What is the flux generally used in 
 smelting iron ? Name the chief chemical changes that take 
 place in a blast furnace. How is cast iron converted into 
 wrought iron and steel ? 
 
 8. How is steel made from pig iron by the Bessemer 
 process ? 
 
 9. Name an ore of each of the following metals : iron, 
 lead, zinc, and mercury. Give a test for a metal in each of 
 the following ways : (a) by flame coloration ; () by the 
 borax bead ; (e) by the blowpipe in charcoal. 
 
 10. How may a ferrous salt be prepared? a ferric salt? 
 Give a special test for each. 
 
 11. Name the ingredients of the furnace charge that 
 would be employed in the manufacture of cast iron from an 
 ore containing ferric oxide mixed with sand. Make a dia- 
 gram of the furnace. 
 
 12. What weight of is required to unite with 21 g. of 
 iron to give the magnetic oxide of iron (Fe g 4 )? What 
 volume will this occupy at 10 C. and 750 mm. ?
 
 56 REVIEW QUESTIONS AND PROBLEMS 
 
 13. Give the names of the different processes for produc- 
 ing steel from cast iron, and define ore and flux. Give 
 formulas for six important compounds of iron. 
 
 14. How would you (a) make ferrous chloride from iron ? 
 (6) ferrous sulphide from ferrous chloride ? (c) ferrous sul- 
 phate from ferrous sulphide ? (d) ferric hydroxide from 
 ferrous sulphate ? 
 
 15. In the above question write the equations for the re- 
 actions after giving the descriptions of the processes, and 
 indicate the color of the product in each case. 
 
 16. How can ferrous sulphate be made from iron and this 
 compound converted into a ferric salt ? How would you test 
 for ferric oxide in the solution ? 
 
 17. Both iron and aluminum become oxidized upon ex- 
 posure to the air. Why does iron gradually disintegrate, 
 and why does aluminum remain not perceptibly changed ? 
 
 18. Why is iron pyrites an objectionable ore from which 
 to obtain iron ? 
 
 19. Russell, in 1869, found that the hydrogen produced 
 by the action of HC1 upon cobalt was 3.4917 per cent of 
 the metal. Calculate the atomic weight of cobalt. 
 
 20. Write the formulas for the following compounds : 
 potassium ferrocyanide, potassium ferricyanide, ferric ferro- 
 cyanide, ferrous ferricyanide, potassium cobalt nitrite, ferric 
 acetate, ferric nitrate, ferrous bromide, nickelic sulphate, 
 cobaltic nitrate. 
 
 21. Write the chemical and ionic equations for the displace- 
 ment of copper by iron in solutions of copper compounds. 
 
 22. What is a slag? How is it produced and what is 
 its use? 
 
 23. What is the method of preparation of platinum, and 
 what metal is likely to be alloyed with it ?
 
 COPPER, SILVER, AND GOLD GROUP 57 
 
 24. When a solution of sodium carbonate is added to a 
 solution of a ferric salt, an hydroxide is precipitated and 
 not a carbonate. How is this explained ? 
 
 25. Give the tests for nickel and cobalt. 
 
 26. What is the only important compound of platinum, 
 and what is the use of platinum in the contact process in 
 the manufacture of H 2 S0 4 ? 
 
 27. Distinguish between chrome iron, nickel steel, spiegel 
 iron, and vanadium steel. 
 
 28. What is the minimum weight of carbon per ton of 
 steel that can be added and yet have the steel take a 
 temper ? 
 
 29. Describe the open-hearth process ; the Siemens-Martin 
 process of manufacturing steel. 
 
 30. State the most important uses of cobalt, its properties, 
 and how and when found. 
 
 31. Give the chemical and the common name of FeS. 
 How can it be prepared in the laboratory ? Give equation. 
 
 CHAPTER XIX 
 COPPER, SILVER, AND GOLD GROUP 
 
 1. Compare copper, silver, and gold in their physical 
 and chemical properties. 
 
 2. What is oxidized silver, German silver, sterling silver? 
 
 3. Write the formulas for the following compounds : 
 cuprous nitrate, cupro'us sulphide, cuprous iodide, cupric 
 acetate, silver cyanide, silver sulphate, silver oxide, aurous 
 bromide, auric chloride, aurous hydroxide, cupric hydroxide. 
 
 4. If 500 g. of silver interact with nitric acid, how much 
 silver nitrate is formed?
 
 58 REVIEW QUESTIONS AND PROBLEMS 
 
 5. Write the equation for the reduction of cupric oxide 
 by hydrogen with heat. 
 
 6. What acid would you use to dissolve silver ? What 
 chemical test would show the difference between a solution 
 containing a silver salt and one containing a zinc salt ? 
 Write equations to illustrate both answers. 
 
 7. Write equations for the reaction between silver and 
 nitric acid ; also for the resulting solution with hydrochloric 
 acid. Describe the visible changes accompanying these 
 reactions. 
 
 8. Describe a process of obtaining copper from one of 
 its ores. Mention (</) the properties of copper, and (6) the 
 important uses. 
 
 9. Write the equation for the reaction of H 2 SO 4 on 
 copper when heated. Explain why the gaseous product 
 obtained differs from that usually produced by the action 
 of an acid on a metal. 
 
 10. Define cupellation. Describe a process of extracting 
 silver from its ores by cupellation. 
 
 11. Calculate the percentage of water of crystallization 
 in crystalline copper sulphate (CuS0 4 5 H 2 O). 
 
 12. An experiment showed that when 2.16 g. of silver 
 were treated with chlorine 2.87 g. of silver chloride were 
 formed. Calculate from this result the atomic weight of 
 silver. 
 
 13. Describe experiments by which you could determine 
 . whether or not an alloy contained silver. 
 
 14. Name the elements that enter into the composition 
 of the following alloys, and give the usual percentage rela- 
 tion : () aluminum bronze ; (/>) brass ; (c) bronze ; (d) Ger- 
 man silver ; (e) gold coin ; (/) gun metal ; (</) nickel coin ; 
 
 A silver coin.
 
 COPPER, SILVER, AND GOLD GROUP 59 
 
 15. How could you prepare pure silver chloride from a 
 silver coin ? 
 
 16. Account for the action of sulphur water and eggs 
 upon silver. 
 
 17. Silver may be cleaned by boiling it in water in an 
 aluminum vessel. Write .the equation for the action involved. 
 
 18. Silver nitrate and mercuric nitrate are both white salts 
 soluble in water. How could you distinguish between them ? 
 
 19. Describe, giving chemical reactions involved, the 
 amalgamated process of refining silver. Why is the silver 
 sulphide first changed into silver chloride ? 
 
 20. Why is silver not used as an electric conductor ? 
 
 21. Describe what takes place when a solution of silver 
 nitrate is electrolyzed (a) with both terminals of platinum ; 
 (A) with both terminals of silver. 
 
 22. What occurs when a solution of copper sulphate is 
 electrolyzed (a) with both electrodes of copper ? (b) with 
 both electrodes of platinum ? 
 
 23. (.) Describe the electrolytic purification of copper; 
 (fi) the method of electrolytic copperplating. 
 
 24. What chemical compound is ordinarily employed in 
 photography ? Describe briefly the chemistry of the different 
 steps taken in making a photograph. 
 
 25. Draw carefully a diagram of an apparatus for passing 
 H over red-hot oxide of copper. Include the details for mak- 
 ing the hydrogen gas and the arrangement for preserving 
 separately the products of the reaction. 
 
 26. State two ways by which an aqueous solution of a 
 copper salt may be distinguished from one of a ferric salt. 
 
 27. Why is plated ware softer than sterling silver? What 
 compound is usually formed when silver tarnishes ? Mention 
 two articles of food that cause silver to tarnish.
 
 60 REVIEW QUESTIONS AND PROBLEMS 
 
 28. How does copper occur in nature ? What is blue 
 vitriol ? Give three tests for copper. 
 
 29. If 4.393 g. of copper precipitate 14.91 g. of silver 
 from a silver nitrate solution, and the atomic weight of 
 silver is 108, what is the atomic weight of copper ? 
 
 30. How would you account for the fact that solutions of 
 the different salts of a metal usually have the same color ? 
 
 31. How would you test for the presence of silver in 
 an ore? 
 
 32. From 10 cc. of a solution of silver nitrate 0.9365 g. 
 of silver chloride were obtained by precipitation with hydro- 
 chloric acid. How many grams of silver nitrate are contained 
 in a liter of the solution ? 
 
 33. Describe the chlorination and the cyanide processes 
 for extracting gold. 
 
 CHAPTER XX 
 CHROMIUM AND MANGANESE GROUP 
 
 1. Name the members of the chromium group. 
 
 2. Distinguish between trivalent and hexavalent 
 chromium. 
 
 3. Name the most important compounds of chromium. 
 
 4. Give the equation for the action of H 2 SO 4 upon 
 potassium chromate, showing all steps. 
 
 5. How is permanganate solution used as a test for 
 organic matter in water ? 
 
 6. Name (a) the most important compounds of man- 
 ganese ; (7>) state their uses ; (e) give their characteristics. 
 
 7. In the preparation of from KC10 g manganese 
 dioxide is used. Explain its action and name the process.
 
 CHROMIUM AND MANGANESE GROUP 61 
 
 8. How may potassium dichromate be converted into 
 potassium chromate and vice versa? 
 
 9. What is chrome iron, and what is the purpose in 
 using chromium in iron ? 
 
 10. Give the tests for Mn and for chromium. 
 
 11. Write the equations for the following reactions: 
 
 1.' Preparation of manganous chloride. 
 
 2. Preparation of manganous hydroxide. 
 
 3. Ferrous sulphate + potassium permanganate = 
 
 4. Ammonium sulphate -f- chromium sulphate = 
 
 5. Potassium chromate + hydrochloric acid = 
 
 12. How many grams of lead chromate can be made from 
 500 g. of potassium dichromate ? 
 
 13. Why is chrome alum called a double salt? What is 
 the meaning ? 
 
 14. How is manganese classified in the groups of the 
 elements ? 
 
 15. Describe the use of manganese in the manufacture of 
 Cl by the Welden process, and give the reactions. 
 
 16. What is known of molybdenum, tungsten, and 
 uranium ? 
 
 17. What is meant by the term " catalysis " ? Give a 
 reaction in which a catalytic agent is used. 
 
 18. What evidence is there from the study of chro- 
 mium and its compounds that oxygen is correctly called 
 acid former ? 
 
 19. How does K 2 Cr 2 7 prevent the "polarization" of a 
 voltaic cell ? What chromium compound is formed in the 
 " dichromate " battery ? 
 
 20. Exactly 20 cc. of a solution containing 15.8 g. of 
 KMnO 4 per liter were needed to react completely with a 
 solution of H./X r How much H 2 2 was there ?
 
 62 REVIEW QUESTIONS AND PROBLEMS 
 
 CHAPTER XXI 
 ORGANIC ACIDS AND COMPOUNDS 
 
 1. What are hydrocarbons and where are they found in 
 nature ? Name some hydrocarbons which occur in illumi- 
 nating gas, and show how you would prepare any one of 
 them. Give the equations. 
 
 2. What volume' of ordinary air would be required for 
 the complete combustion of 15 1. of methane, and what 
 weight of C0 2 would be formed ? 
 
 3. State two physical properties of acetylene. Why does 
 it give out light when burned in the air ? Explain the 
 structure and principle of the acetylene burner designed to 
 prevent the gas from burning with a smoky flame. What 
 two products of combustion are formed when the gas burns 
 in air ? How may the presence of each be detected ? 
 
 4. What is the essential character of the common animal 
 fats ? Explain the process of soap making. What is the 
 difference between " hard " and " soft " soaps ? 
 
 5. Determine the molecular formula for a compound made 
 up as follows : carbon 80 per cent ; hydrogen 20 per cent ; 
 vapor density 15. 
 
 6. The formula for ethane is C 2 H 6 . Calculate the specific 
 gravity of its vapor (a) compared with hydrogen ; (6) com- 
 pared with air. 
 
 7. Find the proportions by weight and by volume in 
 which ethane gas (C 2 Hg) will combine with oxygen. 
 
 8. What is a soap ? Name two soaps soluble in water ; one 
 not soluble in water. Describe a process for making soap. 
 
 9. Mention (a) four hydrocarbons ; (i) four carbohydrates. 
 Write the formula of each compound mentioned.
 
 ORGANIC ACIDS AND COMPOUNDS 63 
 
 10. Describe an experiment to show the presence of each 
 of the following in kerosene oil : () carbon ; (/>) hydrogen. 
 
 11. Mention three organic acids. State the physical and 
 chemical properties of each. 
 
 12. Find the weight of each of the products of combus- 
 tion of 52 g. of camphene (C JO H 16 ). 
 
 13. Describe a method of preparing sulphuric (common) 
 ether, and mention its properties and uses. 
 
 14. Describe the changes that take place when grape 
 juice undergoes () alcoholic fermentation; (/<) acetic fer- 
 mentation, and write the reaction in each case. 
 
 15. Write the graphic formula for marsh gas and find its 
 percentage composition. 
 
 16. Compare common (ethyl) alcohol with wood spirit 
 (methyl) alcohol as to () sources ; (6) important properties 
 and uses. 
 
 17. Name the three classes of carbohydrates and write 
 the chemical formula for each. 
 
 18. How would you bring about the alcoholic fermenta- 
 tion of grape sugar ? Write the equation. Give a test for 
 each of the products of the fermentation. 
 
 19. Write the chemical formulas for the following com- 
 pounds : iodoform, wood alcohol, formaldehyde, ether, acetic 
 acid, starch, chloroform. 
 
 20. Describe cane sugar and acetic acid, touching on 
 (a) production ; (/>) physical properties ; (c) chemical prop- 
 erties ; ((F) chemical formula. 
 
 21. Describe the manufacture of wood alcohol, and state 
 its properties and uses. 
 
 22. Explain the instability of organic substances and 
 state its importance in (</.) nature; (b) fuels.
 
 64 REVIEW QUESTIONS AND PROBLEMS 
 
 23. State the eight divisions of organic compounds, and 
 give the important members of each. 
 
 24. Compare isomerism and allotropy, and give examples 
 of each. 
 
 25. What is saponification, and how is it illustrated ? 
 
 26. Explain how collodion is related to cellulose. 
 
 27. Explain the relation of methyl chloride to wood 
 alcohol. How is methyl chloride used in surgery ? 
 
 28. Write the equation expressing the reaction that takes 
 place when formaldehyde is prepared from wood alcohol. 
 State the relation between formaldehyde and formalin. 
 
 CHAPTER XXII 
 EQUATIONS AND GENERAL FORMULAS 
 
 1. Give the formulas for borax, lime, quartz, green vitriol, 
 caustic soda, carborundum, marble, plaster of Paris, pyrite, 
 and cinnabar. 
 
 2. Give the name, formula, method of preparation, and 
 use of each of two carbides extensively used. 
 
 3. Classify as acids, bases, or salts, and give name of 
 each: NaOH, HF, NaOCl, KC10 8 , NaHC0 8 , NH 4 N0 3 , 
 NH 4 OH, K 2 S0 4 , Ca(OH) 2 , HN0 2 . 
 
 4. Complete the following equations, using formulas : 
 
 1. Barium chloride + sodium sulphate = 
 
 2. Hydrogen sulphide + bismuth chloride = 
 
 3. Ammonium chloride + calcium oxide 
 
 4. Sulphur dioxide + chlorine + water = 
 
 5. Give the name and formula of a binary compound, an 
 acid containing oxygen, a base, and a normal salt.
 
 EQUATIONS AND GENERAL FORMULAS 65 
 
 6. Give the chemical name of each of the following sulv 
 stances : calomel, brimstone, fire damp, choke clamp, muriatic 
 acid, oil of vitriol, copperas. 
 
 7. Complete, using formulas : 
 
 1. Nitric acid -f sodium carbonate = 
 
 2. Ammonium chloride + caustic soda = 
 
 3. Water + metallic sodium = 
 
 4. Manganese dioxide + hydrochloric acid = 
 
 8. Give a chemical method of distinguishing between 
 each of the following: 
 
 1. Hydrogen and carbon monoxide. 
 
 2. Hydrogen chloride and sulphur dioxide. 
 
 3. Oxygen and nitrous oxide. 
 
 4. Nitrogen and carbon dioxide. 
 
 9. Classify these compounds under the headings (a) acids, 
 (&) bases, (c) normal salts, (d) acid salts, (e) anhydrides, 
 (/) oxides: CO 2 , NaHS0 4 , CaCl 2 , PbO, H 8 P0 4 , Ca(OH) 2 , 
 NaSO 8 , Mn0 2 , S0 2 , KC1, KHS0 4 , NH 4 OC1, NaOH, CaF 2 , 
 HI, NH 4 OH, Ca(C10,) a , NaN0 8 . 
 
 10. Complete the following equations, using symbols and 
 formulas : 
 
 1. Ammonium hydroxide + hydrochloric acid = 
 
 2. Ammonia + hydrochloric acid = 
 
 3. Sodium chloride + silver nitrate = 
 
 4. Ferrous sulphide + sulphuric acid = 
 
 5. Lead nitrate + hydrogen sulphide = 
 
 6. Manganese dioxide + hydrochloric acid = 
 
 7. Calcium carbide + water = 
 
 8. Arsenic trioxide -f nascent hydrogen = 
 
 9. Sodium carbonate + nitric acid = 
 
 10. Calcium hydroxide + carbon dioxide =
 
 66 REVIEW QUESTIONS AND PROBLEMS 
 
 11. Complete and balance : 
 
 1. A1 2 (S0 4 ) 3 + KOH = 3. A1(OH) 3 + HC1 = 
 
 2. Al (OH), + KOH = 4. AgN0 8 + KBr = 
 
 5. CaCO 8 + C0 2 + H 2 = 
 
 12. Give chemical names and molecular formulas for the 
 following : borax, Epsom salts, Glauber salts, white vitriol, 
 green vitriol, blue vitriol, iron pyrites, hematite, magnetite, 
 potash, galena, alum, gypsum, and cryolite. 
 
 13. Classify as acids, bases, or salts, and name : H 2 S0 4 , 
 KC1, KHS0 4 , NH 4 OC1, NaOH, CaF 2 , HI, NH 4 OH, Ca(C10 8 ) 2 , 
 NaN0 8 . 
 
 14. For what do the following symbols and formulas stand : 
 S0 2 , C, CH 4 , Fe0 8 , CO 2 , CaCO 3 , Hg, I 2 , H 3 P0 4 , NaOH, (OH), 
 (NH 4 ), NH 3 , Ag, Al, 3 , S., As/)., SnO 2 , and Pb(OH) 2 ? 
 
 15. Complete and balance : 
 
 1. NaOH + H 2 S0 4 = 3. Na + H a O = 
 
 2. Mg + HC1 = 4. NaN0 3 + NH 4 C1 + II. E. = 
 
 5. NaCl + Mn() 2 + H 2 S0 4 + H. E. = 
 NOTE. H. E. stands for heat energy. 
 
 16. Write the formulas for the following compounds and 
 name the acids of which they are salts : sodium hypochlorite, 
 sodium chlorite, sodium chlorate, sodium perchlorate, sodium 
 chloride. 
 
 17. Give the names of the following acids and of the 
 sodium salt of each: HC1, HC10, HC10 2 , HC10 3 , HC10 4 , 
 HNO 2 , HN0 8 , HBr, HI, HF. 
 
 18. Write the equations for the following reactions : 
 
 1. Silver nitrate and sodium chloride. 
 
 2. Aluminum sulphate and potassium hydroxide. 
 
 3. Ammonium chloride and slaked lime. 
 
 4. Sodium chloride, manganese dioxide, and sul- 
 
 phuric acid.
 
 EQUATIONS AND GENERAL FORMULAS 67 
 
 5. Sodium hydroxide and sulphuric acid. 
 
 6. Chlorine and potassium bromide. 
 
 7. Steam and incandescent coke. 
 
 8. Calcium carbide and water. 
 
 9. Calcium hydroxide and carbon dioxide. 
 10. Methane and oxygen (ignited). 
 
 19. Write the equations for the reactions between the 
 following substances : 
 
 1. Calcium carbonate and hydrochloric acid. 
 
 2. Potassium nitrate and sulphuric acid. 
 
 3. Copper and water vapor (heated). 
 
 4. Aluminum sulphate ancPammoiiiuiu hydroxide. 
 
 5. Calcium carbide and water. 
 
 20. Write the formulas for the following : 
 
 1. Potassium chloride. 6. Ferrous sulphide. 
 
 2. Sodium carbonate. 7. Ferric chloride. 
 
 3. Phosphoric acid. 8. Aluminum sulphate. 
 
 4. Sodium cyanide. 9. Cuprous oxide. 
 
 5. Ferric oxide. 10. Manganese dioxide. 
 
 21. Write the equations for the following reactions: 
 
 1. Potassium hydroxide and sulphuric acid. 
 
 2. Calcium hydroxide and sulphuric acid. 
 
 3. Calcium hydroxide and ammonium sulphate. 
 
 4. Ferric chloride and ammonium hydroxide. 
 
 5. Sodium hydroxide and phosphoric acid. 
 
 6. Ammonium nitrate and heat. 
 
 22. Write the formulas for 
 
 1. Sodium carbonate. 4. Arsine. 
 
 2. Lead sulphate. 5. Arsenic trioxide. 
 
 3. Silica. 6. Ammonium sulphide. 
 
 7. ^Normal c;ilcium phosphate.
 
 68 REVIEW QUESTIONS AND PROBLEMS 
 
 23. Write the formulas for 
 
 1. Limestone. 5. Aluminum phosphate. 
 
 2. Secondary sodium phos- 6. Mercurous chloride. 
 
 phate. 7. Barium nitrate. 
 
 3. Cupric sulphate. 8. Acetylene. 
 
 4. Ammonia. 9. Gypsum. 
 
 10. Marsh gas. 
 
 24. Classify as acids, bases, or salts: NaN0 8 , NH 4 C1, 
 HC10, NH 4 OH, BaS0 4 , Ca(NO 8 ) 2 , HC10 4 , Sr(OH) 2 , HN0 2 , 
 Fe(OH) 8 . 
 
 25. Write the formulas for 
 
 1. Barium perchlorate. 6. Sodium perchlorate. 
 
 2. Ammonium sulphate. 7. Calcium hypochlorite. 
 
 3. Strontium nitrate. 8. Barium hydroxide. 
 
 4. Calcium sulphate. 9. Strontium oxide. 
 
 5. Ferric sulphate. 10. Barium nitrate. 
 
 26. Complete and balance : 
 
 1. CaC0 3 + HC1 = 6. Mn0 2 + NaC 1 + H 2 S0 4 = 
 
 2. Mn0 2 + HCl= 7. Zn + H 2 S0 4 = 
 
 3. A1 2 (S0 4 ) 8 + NH 4 OH = 8. CaC 2 + H 2 = 
 
 4. CuS0 4 + H 2 S = 9. H 2 + C (hot) = 
 
 5. KOH + H 8 P0 4 = 10. Cl + KOH = 
 
 11. FeCl 8 + NH 4 OH = 
 
 27. Give the structural formulas of NH 4 C1, NH 4 OH, and 
 (NH 4 ) 2 S0 4 . 
 
 28. Complete and balance : 
 
 1. Na 2 C0 8 + HC1 = 6. Ca,(P0 4 ) 2 + H 2 S0 4 = 
 
 2. CaC0 8 + HN0 8 = 7. NaOH + H 3 P0 4 = 
 
 3. A1 2 (S0 4 ) 8 + KOH = 8. KN0 8 + H 2 SO 4 = 
 
 4. Zn + H 2 S0 4 = 9. Mn0 2 + HC1 = 
 
 5. CuS0 4 + H 2 S= 10. SCyNCyOH + H 2 =
 
 EQUATIONS AND GENERAL FORMULAS 69 
 
 29. Write the formulas for 
 
 1. Marble. 6. Ammonium phosphate. 
 
 2. Primary sodium sulphate. 7. Ammonia. 
 
 3. Aluminum sulphate. 8. Silver nitrate. 
 
 4. Cuprous chloride. 9. Mercuric chloride. 
 
 5. Cupric oxide. 10. Quicklime. 
 
 30. Name the following: (NH 4 ) 2 C0 8 , NH 4 HOO g , NH 4 CN, 
 NH 4 H 2 P0 4 , Au 2 g , Ba(C 2 H 8 2 ) 2 , BaCr0 4 , BiBr s , BiON0 8 , 
 CsCl, NiAs, Os0 4 , K 2 A1 2 O 4 , K 2 PtCl 4 , FeAs0 4 -2H 2 0. 
 
 31. Name the following: NiS 2 , NaHC0 8 , NaAuCl 4 2 H 2 O, 
 SeCl 2 , RuCl 2 , CaAlSi 2 O 8 , SnF 2 , SrC 2 , TaBr fi . 
 
 32. Name the following: NaC10 4 , HC1O, NO, KC1O 2 , 
 KN0 2 , C.N,, H 2 S0 4 , H 2 S 8 O 4 , H 8 PO 4 , HNaC0 8 , Ca(OCl), 
 FeCl 8 , CuBr, HKC0 8 , NH 4 C1, Ca(OH) 2 , H 2 2 , H 8 P0 8 , C 2 H 2 . 
 
 33. Complete the following reactions, using formulas : 
 
 1. Iron + sulphuric acid = 
 
 2. Zinc oxide + nitric acid = 
 
 3. Calcium hydroxide + carbon dioxide = 
 
 4. Marsh gas + oxygen (ignited) = 
 
 5. Hydrogen sulphide + lead nitrate = 
 
 34. Classify into acids, bases, salts, or anhydrides : S0 8 , 
 NaN0 8 , HBr, Ba(OH) 3 , CaS0 4 , P 2 O 5 , H 8 BO 3 , NH 4 OH, 
 H 8 P0 4 , C0 2 . 
 
 35. Complete, using formulas : 
 
 1. Ferrous sulphate -f hydrochloric acid = 
 
 2. Calcium carbonate -f- nitric acid = 
 
 3. Sulphurous acid + sodium hydroxide = 
 
 4. Silver nitrate + potassium bromide = 
 
 5. Ferric oxide + hydrogen = 
 
 6. Phosphorus pentoxide + water =
 
 70 REVIEW QUESTIONS AND PROBLEMS 
 
 36. Write the equations for the preparation of : 
 
 1. Carbon dioxide from calcium carbonate. 
 
 2. Ammonium hydroxide from ammonium chloride. 
 
 3. Chlorine from hydrochloric acid. 
 
 4. Calcium hydroxide from calcium carbonate. 
 
 5. Nitric acid from sodium nitrate. 
 
 37. Complete, using formulas : 
 
 1. Sodium hydroxide + carbon dioxide = 
 
 2. Lead nitrate + hydrogen sulphide = 
 
 3. Calcium hydroxide + nitric acid = 
 
 4. Phosphorus + oxygen = 
 
 5. Sodium carbonate + calcium chloride = 
 
 6. Hydrogen + (hot) copper oxide = 
 
 State which of the above compounds are acids, bases, 
 salts, or anhydrides. 
 
 38. Write the equations for the preparation of () sulphur 
 dioxide ; (6) hydrogen sulphide ; (V) ammonia ; ((f) carbon 
 dioxide; (e) nitric acid. 
 
 39. Give the chemical formulas for the following : dia- 
 mond, carborundum, black lead, marble, sand (pure), washing 
 soda, lye, blue vitriol. 
 
 40. State which of the reactions indicated below will take 
 place in aqueous solution, and which will not, and give 
 the reasons for your conclusion in each case. Complete the 
 equations, using formulas : 
 
 1. Barium chloride + silver nitrate = 
 
 2. Calcium chloride + carbon dioxide + water = 
 
 3. Copper sulphate + zinc = 
 
 4. Ferrous sulphate -f- copper = 
 
 5. Calcium hydroxide + nitric acid = 
 
 41. Name two metals which have a valence of 2 and 3 
 respectively, and write the formulas for the nitrates and 
 sulphates of these metals.
 
 EQUATIONS AND GENERAL FORMULAS 71 
 
 42. Give the chemical names and formulas for the follow- 
 ing: baking soda, brimstone, slaked lime, litharge, quick- 
 silver, oil of vitriol, sal ammoniac, alum, plaster of Paris, 
 quartz, niter. 
 
 43. Write the molecular formulas for ozone, sodium sul- 
 phate, carbon monoxide, aluminum chloride, potassium 
 hydroxide, calcium carbonate, ferric oxide, phosphorus 
 pentoxide, lead iodide, phosphoric acid. 
 
 44. Give the names of the following formulas : Hg (NOg) 2 , 
 CuO, Ag 2 S0 4 , H 2 2 , Br 2 , Au, H 2 S, Pb(OH) 2 , BaC0 8 . 
 
 45. Write the formulas for nitrogen peroxide, carbon 
 monoxide, sulphuric anhydride, calcium hydroxide, cupric 
 oxide, stannic chloride, hydrogen bromide, potassium car- 
 bonate, silver nitrate, lead sulphate. 
 
 46. Write a list of the formulas for the oxides of nitrogen, 
 and show how any of these can react with water. Point out 
 how any two of this series of compounds illustrate the Law 
 of Multiple Proportions. 
 
 47. Write equations showing laboratory methods of pre- 
 paring the following : (a) hydrochloric acid ; (i) sodium 
 carbonate ; (c) ferric hydroxide ; (cf) copper sulphate. 
 
 48. Give the chemical names and formulas for the follow- 
 ing: quicklime, marble, blue vitriol, bicarbonate of soda, 
 litharge, calomel. If any reactions are possible between 
 these substances and dilute sulphuric acid, write equations 
 tor show them. 
 
 49. Write equations for the preparation of () CO 2 ; 
 (l>) NaOH ; (c) H 2 S ; (d) AgCl ; (e) a basic oxide and HC1 ; 
 (/) an acidic oxide and KOH. 
 
 50. Describe the effects observed when chlorine water is 
 added (a) to mercurous chloride ; (It) to potassium iodide 
 solution. What inference do you draw about the reactions 
 that have taken place ?
 
 72 REVIEW QUESTIONS AND PROBLEMS 
 
 51. Write the chemical names of the following: H 2 SO 3 , 
 NaHCO,, H 2 S, Fe 2 (SO 4 ) 8 , P 2 O 5 , and show by equation how 
 each may be prepared. 
 
 52. Write the graphic formula for (a) nitric acid ; (b) cal- 
 cium carbonate ; (c) acetic acid. 
 
 53. Show by equation the bleaching action of (a) Cl ; 
 
 (*) so 2 . 
 
 54. Write the equations for the preparation of the follow- 
 ing acids other than by the direct combination of the elements 
 involved : H 2 S, HN0 8 , H 2 S0 4 , HBr, HC1, H 2 C0 8 , H 8 P0 4 . 
 
 55. Write the equations for the following reactions : 
 
 1. Potassium hydroxide and nitric acid. 
 
 2. Ferrous sulphide and hydrochloric acid. 
 
 3. Barium chloride and sodium sulphate. 
 
 4. Calpium hydroxide and ammonium chloride. 
 
 56. Write the chemical name of each of the following : 
 KHC0 8 , AsH 8 , Ca 8 (P0 4 ) 2 , C 6 H 12 6 , (C 2 H 5 ) 2 0. 
 
 57. Name and write the formulas for two oxides of 
 phosphorus and the acid corresponding to each. 
 
 58. Write the formula and give the chemical name of 
 saltpeter, laughing gas, sugar of lead, white vitriol, Glauber 
 salts, corrosive sublimate, plaster of Paris. 
 
 59. Describe minutely, giving chemical equations to show 
 the changes which take place : 
 
 1. When strong nitric acid reacts with metallic 
 
 copper. 
 
 2. When hydrogen sulphide is passed into a solution 
 
 of mercuric chloride. 
 
 3. When ammonium sulphate is heated with a solu- 
 
 tion of sodium hydroxide. 
 
 4. When bromine water and sulphurous acid are 
 
 mixed.
 
 EQUATIONS AND GENERAL FORMULAS 73 
 
 60. () Complete, using formulas : 
 
 1. Baric nitrate + potassic sulphate = 
 
 2. Ammonic chloride (solid) + calcic hydroxide 
 
 (solid) = 
 
 3. Sulphurous oxide +- oxygen = 
 
 (fi) Give equations for making sulphuretted hydrogen. 
 
 61. Write the formulas for: 
 
 1. Three chlorides insoluble in water. 
 
 2. Four sulphates insoluble in water. 
 
 3. Two sulphides insoluble in water. 
 
 4. One carbonate soluble in water. 
 
 62. Name the following: NaCIO, NO, KN0 2 , H 2 S0 8 , 
 FeCl 8 , H 8 P0 4 , HP0 8 , Cu a O, CuBr 2 , PbO 2 . 
 
 63. Write the equations for the chemical reactions below : 
 
 1. Ammonium chloride and slaked lime. 
 
 2. Manganese dioxide and hydrochloric acid. 
 
 3. Nitric acid and sodium hydroxide. 
 
 4. Sodium nitrate and sulphuric acid. 
 
 5. Manganese dioxide, sodium chloride, and sulphuric 
 
 acid. 
 
 64. Write equations for the following reactions : 
 
 1. Between lead peroxide and aqueous hydrochloric 
 
 acid. 
 
 2. On subliming mercuric sulphate and aqueous com- 
 
 mon salt. 
 
 3. Between aluminum sulphate and aqueous ammonia. 
 
 4. Between aluminum and potassium hydroxide. 
 
 5. Between copper sulphate and sodium hydroxide. 
 
 65. Write the formula for phosphoric acid, acetic acid, 
 hydriodic acid, chromic acid, silicic acid, sulphurous acid, 
 nitrous acid.
 
 74 REVIEW QUESTIONS AND PROBLEMS . 
 
 CHAPTER XXIII 
 
 QUESTIONS AND CALCULATIONS 
 
 A. PERCENTAGE COMPOSITION 
 
 1. Find the percentage composition of carbon in () CH 4 ; 
 (ft) C 2 H 2 ; (c) C 2 H 4 ; (rZ) COS; () C 4 H 10 ; (/) C 6 H 10 O 5 . 
 
 2. Calculate the percentage composition of the follow- 
 ing compounds : carbon dioxide, ammonia, ferric oxide, ace- 
 tic acid, calcium sulphate, cream of tartar, ferrous sulphate, 
 alum. 
 
 3. How much sodium in (a) 10 g. of NaOH ? (ft) 19 g. of 
 Na 2 SO 4 ? (e) 15 g. of NaCl ? (d) 22 g. of NaHS0 4 ? 
 
 4. Calculate the percentage composition of (a) galena; 
 (7/) pitchblende. 
 
 5. How much anhydrous salt in (-) a kilogram of crys- 
 talline Glauber salts ? (b) alum ? (e) Epsom salts ? (//) sal 
 soda ? (e) copper sulphate ? 
 
 6. Find the percentage of the elements in a sample of 
 air which consists of 12.37 g. of N and 3.63 g. of O. 
 
 7. Calculate the percentage composition of (a) magnetic 
 oxide of iron (Fe g O 4 ); (&) crystallized sodium carbonate 
 (Na 2 CCylOH 2 0). 
 
 8. How many grams of argon can be obtained from 
 1500 kg. of normal air ? 
 
 9. Calculate the percentage composition of () nitric 
 acid ; (b) potassium nitrate ; (c) sodium nitrate. 
 
 10. Calculate the percentage composition of () alcohol 
 (C 2 H 6 0); (6) acetic acid (C^O,); (c) cane sugar (CJH.OJ ; 
 (d) acetone (C g H 6 O). 
 
 11. Find the percentage composition of ether.
 
 QUESTIONS AND OAL(TLATrONS 75 
 
 R ATOMIC AND MOLECULAR WEIGHTS 
 
 1. Suppose 10 g. of lead yield 14.642 g. of lead sulphate 
 (PbS0 4 ). Calculate the atomic weights of S on the assump- 
 tion that the atomic weights of lead and oxygen are 206.91 
 and 16 respectively. 
 
 2. A certain weight of copper oxide, when heated in a 
 current of H, lost 59.789 g. of and formed 67.282 g. of 
 water. If = 16, what is the atomic weight of H ? 
 
 3. One gram of a certain metal was dissolved in HC1 
 and gave 1242 cc. of H at C. and 760 mm. The specific 
 heat was found to be 23. Calculate the equivalent weight 
 and the atomic weight. What would be the valence of the 
 metal ? the formula of the chloride ? 
 
 4. Suppose 13.67 g. of a compound of lead and oxygen 
 contained 12.39 g. of lead and 1.28 g. of oxygen ; what is 
 the formula of the compound if the atomic weight of lead 
 is 206.9 ? 
 
 5. If 63.8351 g. of silver iodide yield 38.9656 g. of silver 
 chloride, what is the atomic weight of iodine if 107.85 and 
 35.46 are accepted as the atomic weights of silver and 
 chlorine respectively ? 
 
 6. What is the equivalent of Ni if it dissolves in acids 
 with the evolution of a mass of H equal to 3.411 per 
 cent of its own mass ? What is its atomic weight if it is 
 bivalent ? 
 
 7. If the atomic weight of Ag is 197.94, and if the same 
 electric current, on passing through solutions of Ag and 
 Cu salts, precipitates weights of the metals in the ratio of 
 l(Cu) : 3.408 (Ag), what is the atomic weight of copper ? 
 
 8. The specific heat of P is 0.189 and its vapor density 
 referred to hydrogen is 62. How many atoms are there in 
 a molecule of phosphorus gas ?
 
 76 REVIEW QUESTIONS AND PROBLEMS 
 
 9. Dumas synthesized silver sulphide (Ag. 2 S), finding the 
 ratio of the weights of silver and of the sulphide to be 
 112.1943 : 128.8288. The atomic weight of silver is 107.94 ; 
 find the atomic weight of S. 
 
 10. A chemist converted 16.6450 g. of bismuth oxide in- 
 to 25.2551 g. of bismuth sulphate (Bi 2 (S0 4 ) 3 ). The atomic 
 weight of S is 32.06. Calculate that of bismuth. 
 
 11. Heinrichson heated 31.20762 g. of calcite and obtained 
 17.49526 g. of quicklime. If the atomic weights of oxygen 
 and carbon are 16.00 and 12.001 respectively, what is the 
 atomic weight of calcium ? 
 
 12. A chemist obtained from 59.4763 g. of magnesium 
 sulphate 19.9379 g. of magnesia. Calculate from this data 
 the atomic weight of Mg. 
 
 13. If 3.17 g. of iron form 4.53 g. of Fe 2 O 8 , what is the 
 atomic weight of iron ? 
 
 14. If 200 parts of BaCl 2 give 224.2 of BaS0 4 , what is 
 the atomic weight of barium ? 
 
 15. The molecular weight of lead oxide (PbO) is 221.3. 
 The per cent of lead is 92.81. Specific heat of lead is 0.031. 
 What is its atomic weight ? 
 
 16. The specific heat of Ag is 0.056. AVhat is its atomic 
 weight ? 
 
 17. If 4.5 g. of Hg unite with oxygen to form 4.86 g. of 
 mercuric oxide, and the specific heat of mercury is 0.032, 
 what is its atomic weight ? 
 
 18. A metal yields a chloride containing 66.14 per cent 
 of chlorine and having the specific gravity 7.44. What is 
 its atomic weight ? 
 
 19. Dumas found that 2.399 g. of aluminum chloride re- 
 quired 5.802 g. of silver for the complete precipitation of 
 the chlorine. Calculate the atomic weight of aluminum.
 
 QUESTIONS AND CALCULATIONS 77 
 
 Calculate the molecular weights of the following : 
 
 20. NH 4 C1; (NH 4 ) 2 C0 8 ; NH 4 HC0 8 ; (NH 4 ) 2 Cr0 4 ; NH 4 CN; 
 NH 4 F; (NH 4 ) 2 Mg0 4 ; NH 4 NO 8 ; NH 4 NO 2 ; 
 
 21. CaC0 8 ; CaAl 2 4 ; Ca(HC0 8 ) 2 ; CaO; Ca^lO^; CaF 2 ; 
 Ca(OH) 2 ; CaI 2 ; CaS0 4 ; C0 2 ; 
 
 22. FeAs0 4 .2H 2 0; FeCl g ; FeC0 8 ; Fe 8 4 ; FeS; 
 
 23. Pb(C 2 H 8 2 ) 2 ; Pb(B0 2 ) 2 .H 2 0; PbBr 2 ; Pb(N0 8 ) 2 ; 
 PbO; Pb 3 4 ; 
 
 24. MgF 2 ; MgS0 4 .7H 2 O; MnCl 2 ; Mn(OH) 2 ; HgCl 2 ; 
 HgS0 4 ; 
 
 25. NiAs; NiCC^O,),; NiC0 8 ; HN0 8 ; N 2 ; N 2 O; NOC1; 
 
 26. Sn0 2 ; Sn 2 Fe(CN) 6 ; SnF 2 ; SrBr 2 ; SrC 2 ; 
 H 2 0; H 2 S0 4 ; SOBr 2 ; TaBr 5 ; 
 
 27. Mn 2 8 -H 2 0; (CaBa)C0 8 ; CaC0 8 (MgFe)C0 8 ; 
 (K 2 Ba) A^Sip^ ; (NaK) AlSi g 8 . 
 
 C. SIMPLEST FORMULAS 
 
 1. Calculate the simplest formula for the compounds hav- 
 ing the percentage composition (a) N = 82.35, H = 17.64 ; 
 (b) N = 26.17, Cl = 66.35, H = 7.48. 
 
 2. Calculate the simplest formula for the substances hav- 
 ing the composition (a) = 76.19, H = 1.58, N = 22.22 ; 
 (/>) N = 13.86, K = 38.61, = 47.52. 
 
 3. Find the simplest formulas for the substances hav- 
 ing the following composition : (a) H = 1.58, N = 22.22, 
 = 76.19 ; (i) = 47.53, N = 13.86, K = 38.61. 
 
 4. Calculate the simplest formula for the compounds hav- 
 ing the percentage composition : (a) N = 82.353, H = 17.647 ; 
 (b) = 30, Fe = 70 ; (c) H = 1, C = 12, K = 39, O = 48. 
 
 5. What is the simplest formula for a compound having 
 the composition H = 7.69 and C = 92.3 ?
 
 78 REVIEW QUESTIONS AND PROBLEMS 
 
 6. Calculate the simplest formulas for the substances 
 having the composition (a) C = 40, H = 6.67, = 53.33 ; 
 (ft) C = 16.8, H = 5.26, N = 36.84, S = 42.1 ; (c) C = 54.55, 
 H = 9.09, = 36.36. 
 
 7. Calculate the formulas for the following : 
 
 Cu = 34.46. CaO = 43.45. Ag = 53.15. Lithia=6.43. 
 Fe = 30.59. A1 2 8 = 17.68. Cu = 31.08. Alumina = 29.26. 
 8 = 34.95. Si0 2 = 38.87. 8 = 15.77. Silica =64.31. 
 
 8. What is the simplest formula for a mineral whose 
 percentage composition is as follows: Ca, 50.12 per cent; 
 C, 12.04 per cent ; and 0, 47.84 per cent. 
 
 9. A liter of gas weighs 1.16 g. Is its formula CH, C 2 H 2 , 
 orC 4 H 4 ? 
 
 10. The analysis of a certain compound gave the follow- 
 ing results : 
 
 1. C =12.00 2. 11.69 3. 11.83 
 
 H = 3.98 4.02 4.00 
 
 N = 6.77 6.80 6.78 
 
 Br = 77.56 77.61 77.64 
 
 What is its formula ? 
 
 D. MOLECULAR FOKMULAS 
 
 1. The vapor density of steam is 9. The percentage 
 composition of water is H = 11.11, = 88.89. What is 
 the formula of steam ? 
 
 2. Find the formula for a hydrocarbon that contains an 
 equal number of hydrogen and carbon atoms, and the vapor 
 of which has a density (air) of 2. 
 
 3. If 750 cc. of CO weighs 0.94 g., what is the molecular 
 weight of the compound ?
 
 ni KS'I 'IONS AND CALCULATIONS 79 
 
 4. Calculate the formulas for the compounds having the 
 following percentage composition and vapor density : 
 
 1. C = 92.3 per cent, H = 7.7 per cent, vapor den- 
 
 sity == 39. 
 
 2. C = 73.8 per cent, H = 8.7 per cent, N = 17.5 per 
 
 cent, vapor density = 80.2. 
 
 3. C = 39.9 per cent, H = 6.7 per cent, O = 53.4 per 
 
 cent, vapor density = 30.5. 
 
 4. C = 10.04 per cent, H = 0.84 per cent, Cl = 89.12 
 
 per cent, vapor density = 59.7. 
 
 5. The vapor density of Cl is 35.45. What is its molecular 
 weight ? 
 
 6. What is the formula for mercuric chloride as deduced 
 from the following data : weight of flask full of vapor at 
 350 and 758.4 mm. = 27.401 g ; capacity of flask = 250 cc. ? 
 
 7. The specific heat of P is, 0.189 and its vapor density 
 referred to H is 62. How many atoms are there in a mole- 
 cule of phosphorus gas? 
 
 8. The gas density of sodium vapor is 11.5. Calculate 
 the number of atoms in a molecule of sodium vapor. 
 
 9. A gaseous compound of H and C is found to contain 
 12 parts by weight of carbon to 1 part of hydrogen. Its 
 gas density is 13. What is its formula ? 
 
 10. If 1500 cc. of CO gas weigh 1.8816 g., what is the 
 molecular weight of the compound ? 
 
 11. Calculate the molecular formulas for the compounds 
 corresponding to the following data : 
 
 1. C = 73.8, H = 8.7, N = 17.1, vapor density = 5.03. 
 
 2. C = 92.3, H = 7.7, vapor density = 2.425. 
 
 3. C = 39.9, H = 0.7, = 53.4, vapor density = 1.906. 
 
 Yapm- density in rach case is referred to oxygen.
 
 80 REVIEW QUESTIONS AND PROBLEMS 
 
 12. An oxide of carbon contains 42.85 per cent of carbon. 
 Calculate the molecular formula if a liter of the gas weighs 
 1.25 g. under standard conditions. 
 
 13. A volatile liquid contains 37.5 per cent of carbon, 
 50 per cent of oxygen, and 12.5 per cent of hydrogen. A liter 
 of the vapor weighs about 16 times that of hydrogen. What 
 is the molecular formula ? 
 
 14. If a hydrocarbon contains 80 per cent carbon and a 
 liter of it weighs 1.346 g., what is its formula ? 
 
 15. Employ Avogadro's hypothesis in calculating the 
 atomic weight of oxygen from the following data : carbonic 
 acid gas, steam, laughing gas, and sulphurous anhydride con- 
 tain in the order named 72.73, 88.89, 36.364, and 50.00 per 
 cent by weight of oxygen ; and their densities referred to 
 H are, in the same order, 22, 9, 22, and 32. 
 
 16. A gas has the formula C 3 H g . Is it lighter or heavier 
 than air ? 
 
 17. A liter of arsine weighs 3.49 g. under standard condi- 
 tions ; find its molecular weight. 
 
 18. What is the molecular weight of marsh gas, 3 1. of 
 which weigh 2.15 g.? 
 
 19. Calculate the molecular weights of the following gases 
 from their vapor densities : (a) chlorine, 35.5 ; (7>) hydro- 
 chloric acid, 18.25 ; (c) ammonia, 8.5 ; (<7) nitrogen, 1'4 ; 
 (e) steam, 9. 
 
 20. Sulphur dioxide is 2.22 times as heavy as air ; find 
 its density and the molecular weight. 
 
 21. The specific gravity of ammonia compared to hydro- 
 , gen is 8.5. What is its molecular weight ? Explain the 
 
 steps by which it is obtained. 
 
 22. At what temperature does air have the density of 
 H at 0C.?
 
 WEIGHTS AND VOLUMES FROM EQUATIONS 81 
 
 CHAPTER XXIV 
 WEIGHTS AND VOLUMES FROM EQUATIONS 
 
 1. What weight of hydrogen will be required for the com- 
 plete reduction of 10 g. of CuO ? What will be the volume 
 at a temperature of 15 C. and 740 mm. pressure ? 
 
 2. What weight of potassium chlorate (KC10 8 ) would be 
 needed to generate sufficient oxygen to fill a cylinder of 
 50 1. capacity under a pressure of 1000 cm. of mercury and 
 a temperature of 15 C. ? 
 
 3. The capacity of a balloon is 10,000 cu. ft. How much 
 would it cost to fill it with hydrogen at a pressure of 800 mm. 
 and at a temperature of 23 C., the H being made from Zn 
 costing 20 ct. per pound and sulphuric acid costing 8 ct. 
 per pound? 
 
 4. What weight of ammonium chloride will yield 1 1. of am- 
 monia at a pressure of 740 mm. and a temperature of 22 C. ? 
 
 5. What would be the volume under standard conditions 
 of a quantity of air that occupies 200 cc. at 20 C. under a 
 pressure of 740 mm. of mercury ? 
 
 6. How many liters of nitrogen monoxide can be prepared 
 from 100 g. of ammonium nitrate ? 
 
 '7. What volume of a solution of H 2 S0 4 that contains 
 40 g. of H 2 S0 4 in one liter will be required for the exact 
 neutralization of 10 cc. of a solution of NaOH containing 
 20 g. of NaOH to one liter ? 
 
 8. What volume of ammonia gas, temperature 20 C., pres- 
 sure 740 mm., can be obtained from 214 g. of sal ammoniac, 
 and how should one proceed to prepare it ? 
 
 9. How much sodic chloride may te formed from 10 g. 
 of crystallized sodic carbonate (Na a CO, 10 H/)) ?
 
 82 REVIEW QUESTIONS AND PROBLEMS 
 
 10. How much CO 2 by weight and by volume can be ob- 
 tained from 53 g. of sodium carbonate ? What volume would 
 the gas occupy at 20 C. and 750 mm. pressure ? 
 
 11. Calculate the volume of C0 2 at 0C. and 760mm. 
 that can be made from 50 g. of calcium carbonate and an 
 excess of HC1. 
 
 12. What volume will 25 kg. of oxygen occupy at a tem- 
 perature of 18 C. and a pressure of 740 mm.? 
 
 13. What weight of sulphur is necessary to produce 100 1. 
 of SO 2 at a temperature of 20 C. and a pressure of two 
 atmospheres ? 
 
 14. How many cubic centimeters of H 2 SO 4 , containing 
 49 g. of H 2 S0 4 per liter, will be required to neutralize 2 g. 
 of NaOH ? 
 
 15. Find the number of grams of H 2 S0 4 required to unite 
 with 176 g. of iron sulphide to form H 2 S. 
 
 16. How many liters of oxygen at standard conditions 
 would be formed by the complete decomposition of 25 g. of 
 mercuric oxide ? 
 
 17. How many tons of oil of vitriol containing 70 per cent 
 H 2 SO 4 are needed to convert 100 t. of salt into salt cake? 
 
 18. How much sulphuric acid and potassium nitrate 
 would be required to prepare 100 g. of HN0 8 ? 
 
 19. Compute the weight of KOH required for the exact 
 neutralization of the total quantity of HC1 obtained from 
 175.5 g. of NaOH by the action of H 2 S0 4 . 
 
 20. A solution of 5 g. of potassium iodide is precipitated 
 with silver nitrate. W'hat will be the weight of the precipi- 
 tate of silver iodide ? 
 
 21. If sodium nitrate, ammonium nitrate, and potassium 
 nitrate were the same price per pound, which would be 
 cheapest to use for preparing nitric acid, and why ?
 
 WEIGHTS AND VOLUMES FROM EQUATIONS 83 
 
 22. What relative weights of cupric oxide and cuprous 
 oxide are procurable from the same weight of copper ? 
 
 23. Compare the weights of aluminum and zinc necessary 
 for the production of equal weights of hydrogen by the 
 interaction with an acid. 
 
 24. What weight of H 2 S0 4 can be prepared from 100 g. 
 of sulphur ? 
 
 25. What weight of potassium bromate can be obtained 
 by neutralizing 1520 g. of bromine with potash ? 
 
 26. What weight of limestone is needed to convert 90 tons 
 of soda crystals into sodium bicarbonate ? 
 
 27. How many grams of CO 2 will combine with 100 g. of 
 CaO to form CaCO 8 ? 
 
 28. How much CaSO 4 can be formed from 37 g. of CaCl 2 ? 
 
 29. What weight of Al 2 O g will be needed to prepare 94.8 g. 
 of potash alum ? 
 
 30. What weight of sodium carbonate can be made from 
 500 kg. of common salt ? 
 
 31. Assume that thermit contains 75 per cent iron oxide ; 
 how much of the mixture would be required to produce 6 Ib. 
 of metallic iron ? 
 
 32. Find the oxygen necessary to burn 100 g. of CS 2 . 
 
 33. How many grams of iron sulphide are necessary to 
 prepare 100 1. of hydrosulphuric acid when the laboratory 
 conditions are 17 C. and the pressure 740 mm. ? 
 
 34. What weight of sodium chloride is necessary to pre- 
 pare sufficient hydrochloric acid to saturate 1 1. of water 
 under standard conditions ? 
 
 35. On the supposition that calcium carbide costs 12 ct. 
 a kilogram, what would be the cost of an amount suffi- 
 cient to generate 100 1. of acetylene measured at 20 C. and 
 TlOiiiiu.?
 
 84 REVIEW QUESTIONS AND PROBLEMS 
 
 36. What weight of sodium carbonate crystals will 1 kg. 
 of the anhydrous salt yield ? 
 
 37. Write the equations for the preparation of 3 kg. of 
 KOH by three different methods. 
 
 38. Supposing bauxite to be aluminum hydroxide, what 
 weight of it is necessary for the prepai-ation of 100 kg. 
 of Al? 
 
 39. How much water is necessary to convert 50 g. of 
 P 2 5 into hydrogen phosphite ? 
 
 40. How much carbon would be necessary to convert 50 g. 
 of CuO into pure copper ? 
 
 41. How much nitric and sulphuric acid is needed to pre- 
 pare nitric acid enough to exactly neutralize 5 Ib. of chalk ? 
 
 42. How many tons of coke containing 97 per cent carbon 
 are required to reduce 388 t. of hematite ? 
 
 43. In burning 27 g. of alcohol find the weight of the 
 products. 
 
 44. What weight of Cl can be prepared from 78 g. of rock 
 salt containing 99 per cent NaCI ? How much Mn0 2 and 
 H 2 S0 4 would be required to carry out the reaction ? What 
 volume would the Cl occupy under standard conditions, and 
 what volume of HC1 would be formed ? 
 
 45. How much metallic iron can be made by reducing 
 230 g. of ferric oxide ? 
 
 46. Calculate the volume of a solution of H 2 S0 4 , den- 
 sity 1.8 and containing 89 per cent pure acid, that would 
 be required to make 200 g. of HC1 by acting on sodium 
 chloride. 
 
 47. What weight of ammonium chloride, when acted 
 upon by calcium hydroxide, is required to produce 17 g. of 
 ammonia gas, and what weight of calcium chloride is formed 
 at the same time ?
 
 MISCELLANEOUS QUESTIONS AND PROBLEMS 85 
 
 48. To neutralize completely 196 g. of H^SO^ what weight 
 of crystallized sodium carbonate (Na 2 C0 8 10 H 2 0) is re- 
 quired ? The volume of C0 2 evolved is approximately 4450 cc. 
 under standard conditions. Calculate its volume at 890 mm. 
 pressure and 27 C. 
 
 49. What volume of nitrous oxide (N 2 0) measured at 
 C. and 750 mm. would be evolved by the decomposition 
 of 10 g. of ammonium nitrate, assuming the weight of 1 1. of 
 nitrous oxide at C. and 760 mm. to be 1.97 g. ? 
 
 CHAPTER XXV 
 MISCELLANEOUS QUESTIONS AND PROBLEMS 
 
 1. Mention the constituents of water and give their 
 properties by volume and by weight. Compare them as to 
 physical and chemical properties. 
 
 2. State and illustrate the Law of Multiple Proportions. 
 
 3. Find the percentage composition of H 2 S0 4 . How 
 many grains of SO 2 can be set free by the action of 325 g. 
 of the acid on copper ? 
 
 4. Describe the usual methods of preparing ammonia on 
 a commercial scale. Write the equation. 
 
 5. Describe an experiment illustrating the bleaching 
 properties of S0 2 . Explain. 
 
 6. Distinguish between () allotropism and isomerism; 
 (ft) efflorescence and deliquescence ; (c) hard and soft water. 
 
 7. Mention three distinct allotropic forms of carbon. 
 Compare the physical properties of the forms mentioned. 
 
 8. Describe a method of manufacturing matches. Write 
 two reactions that take place when a common friction match 
 is ignited.
 
 86 REVIEW QUESTIONS AND PROBLEMS 
 
 9. Distinguish between (a) a physical change and a 
 chemical change ; (&) between a mixture and a chemical 
 compound; (c) illustrate each. 
 
 10. Mention the constituent metals of these alloys : bell 
 metal, pewter, brass, soft solder, German silver, type metal, 
 Babbitt metal. 
 
 11. Write the chemical name of each: white lead, blue 
 vitriol, calomel, gypsum, caustic potash, copperas. 
 
 12. Describe a method of preparing phosphorus and write 
 the reactions. % 
 
 13. Find the weight of the products of combustion when 
 26 g. of alcohol (C 2 H 6 0) are burned. 
 
 14. Write the graphic formula of hydrogen arsenide and 
 the reaction for its complete combustion. 
 
 15. Describe an experiment to show that a metal changes 
 in weight when heated in air. Explain. 
 
 16. What is a solution ? Describe an experiment to illus- 
 trate (a) a saturated solution ; (A) a supersaturated solution. 
 
 17. Describe a method of preparing nitrogen and make a 
 sketch of the apparatus. Give the important physical and 
 chemical properties of N. 
 
 18. Give the important physical and chemical properties 
 of bromine. Mention one source and two uses of bromine. 
 
 19. Describe a test to show the presence of each of the 
 following : oxygen, iodine, sodium, carbon dioxide, lead. 
 
 20. A liter of gas under standard conditions weighs 
 2.0608 g. Find (a) its vapor density ; (7>) its molecular 
 weight. 
 
 21. Name four important constituents of the air and give 
 the relation of each to plant and animal life. 
 
 22. Describe the preparation of nitrous oxide, writing 
 the reaction, and give the important properties.
 
 MISCELLANEOUS QUESTIONS AND PROBLEMS 87 
 
 23. Describe the process by which the pig iron of com- 
 merce is obtained from the ore by means of a blast furnace. 
 
 24. Name the four most important constituents of ordinary 
 illuminating gas. Give the relative importance of these 
 constituents in the production of (a) light; (6) heat. 
 
 25. Describe the Bessemer process of manufacturing steel 
 and make a tabular statement of the physical and chemical 
 difference between wrought iron and cast iron. 
 
 26. What substance did you employ in the laboratory 
 preparation of hydrochloric acid ? Why was each substance 
 selected ? 
 
 27. Describe the action and explain what occurs when 
 chlorine water is added to a solution of potassium iodide 
 containing starch. 
 
 28. Give three methods for collecting gases and state 
 the conditions under which each may be advantageously 
 employed. 
 
 29. How many cubic centimeters of H 2 SO 4 , containing 
 49 g. per liter, will be required to neutralize 2 g. of sodium 
 hydroxide ? 
 
 30. Describe the preparation of hydrogen gas and make 
 a sketch of the apparatus used. How can it be proved ex- 
 perimentally that water is formed when H burns ? 
 
 31. () How is coal gas manufactured ? () How could 
 you show by experiment that particles of solid carbon are 
 present in a luminous flame of coal gas ? (c) Why is a 
 Bunsen flame nonluminous ? 
 
 32. Describe the process by which metallic aluminum is 
 manufactured. Describe the reaction that takes place be- 
 tween metallic aluminum and ferric oxide when a mixture 
 of the two is ignited. What practical applications are made 
 of this reaction ?
 
 88 REVIEW QUESTIONS AND PROBLEMS 
 
 33. What is meant by the term " catalysis " ? tfame three 
 processes or reactions where a catalytic agent is present. 
 
 34. Describe the essential features of the mechanical fil- 
 tration process for the purification of large water supplies. 
 
 35. What occurs when a solution of copper sulphate is 
 electrolyzed (a) with both electrodes of platinum ? (i) with 
 both electrodes of copper? Describe the electrolytic puri- 
 fication of crude copper. 
 
 36. Define basic anhydride and acid anhydride; give an 
 example of each. What is a dibasic acid ? Give examples. 
 
 37. Describe in detail the Le Blanc process for the 
 manufacture of soda. 
 
 38. Discuss the periodic classification of the elements. 
 
 39. Explain briefly two practical methods of determining 
 the combining weights of oxygen and hydrogen. 
 
 40. How may lime be shown to be the oxide of a metal ? 
 
 41. How may sulphuretted hydrogen be made? Give 
 the properties and uses of this substance. 
 
 42. What is soap ? How is it made ? What is the 
 difference between hard soap and soft soap ? 
 
 43. Name three substances occurring in nature that are 
 composed of calcium carbonate. What substances are formed 
 when calcium carbonate is highly heated ? What change 
 takes place when water is added to the solid product thus 
 formed ? What use is made of the latter substance ? What 
 chemical change occurs when it is exposed to the air ? 
 
 44. What is plaster of Paris ? What chemical difference 
 is there between the hardening of mortar and the setting 
 of plaster of Paris ? 
 
 45. State by what experiments you could find out whether 
 or not a compound (a) contains water of crystallization; 
 (i) is efflorescent ; (c) gives ions in dissolving ; (d) is an acid.
 
 MISCELLANEOUS QUESTIONS AND PROBLEMS 80 
 
 46. What experiments should you make to distinguish 
 between (a) magnesium oxide and flour? (7>) potassium 
 chloride and potassium bromide ? 
 
 47. State the practical use and explain the efficiency of 
 the Davy safety lamp. 
 
 48. Mention the chemical name and write the formula of 
 each of two oxides of phosphorus, and describe a method 
 of preparing each. 
 
 49. Define kindling temperature. Mention, in the order of 
 their kindling points, charcoal, sulphur, coal, phosphorus. 
 
 50. Describe, writing the reactions, a method of preparing 
 ammonia by the action of an alkali on an ammonium salt. 
 
 51. Define and illustrate filtrate, reagent, triad, halogen, 
 positive element, hydroxide, isomerism. 
 
 52. Distinguish in meaning between the following suffixes 
 when used in names of chemical compounds : (a) ous and 
 ic : () ite and ate ; (c) and the prefixes hyjjo and per. 
 
 53. Find under standard conditions the weight of 1 1. 
 of CO. 
 
 54. Define fermentation. Describe a laboratory experi- 
 ment to illustrate fermentation, writing the reactions. 
 
 55. Describe the occurrence of S in nature. Describe the 
 process of extracting sulphur from one of its ores. 
 
 56. Describe the manufacture of safety matches and state 
 why they are safer than other matches. Write the chemical 
 reactions that occur when safety matches are ignited. 
 
 57. Describe the process of extracting mercury from one 
 of its ores, writing the reaction. Mention the important 
 physical properties and the principal uses of mercury. 
 
 58. In what compound does chlorine usually occur in 
 nature (give chemical and common name)? Show by equa- 
 tion how free chlorine is obtained from this body.
 
 90 REVIEW QUESTIONS AND PROBLEMS 
 
 59. How is sulphur dioxide made from sulphur and how 
 is sulphuric acid made from it ? Write equations. 
 
 60. Show by equations how calcium carbonate decom- 
 poses on heating and how it reacts with dilute H 2 SO 4 . Give 
 the common names of the products of both reactions. 
 
 61. Point out the chemical similarity between chlorine, 
 bromine, and iodine. What is this group called ? How is 
 each of these elements set free from a salt containing it ? 
 
 62. Give the Laws of Definite and Multiple Proportion 
 and point out what relation they have to the atomic theory. 
 
 63. What is the basis of the Mendeleeff classification ? 
 What evidence have we that this is a natural classification ? 
 Discuss the properties of the elements in some natural family 
 in such a way as to show their apparent relation. 
 
 64. Define the terms " atom," " valence," " equivalent," 
 and " gram-molecule." Explain the following processes : dis- 
 tillation, sublimation, electrolysis, neutralization, reduction, 
 fermentation, precipitation ? 
 
 65. To what constituents do acids owe their characteris- 
 tic properties ? Does this substance impart these proper- 
 ties to all its compounds ? What is the theory advanced to 
 explain the facts embraced in your answer? How do we 
 explain the fact that some acids are stronger than others ? 
 Name some other facts which the above-mentioned theory 
 explains. 
 
 66. One volume of oxygen at 100 C. will go to form how 
 many volumes of steam under the same conditions ? How 
 will the number of molecules of each compare ? What in- 
 ference can be drawn from the last answer as to the char- 
 acter of the oxygen molecule ? How do we account for 
 the increase in the density when oxygen is converted into 
 ozone ?
 
 MISCELLANEOUS QUESTIONS AND PROBLEMS 91 
 
 67. Give an account of the manufacture of H 2 S0 4 . Write 
 the equations. How are the pan acid and concentrated acid 
 obtained from the chamber acid? Give the uses to which 
 this acid is put. 
 
 68. Define the terms " acid," " base," and " salt." Discuss 
 the process of neutralization. What is the modern concep- 
 tion as to the condition of acids, bases, and salts in dilute 
 aqueous solutions ? 
 
 69. Describe the Solway process for the manufacture of 
 soda, giving the reactions. 
 
 70. State the Law of Gay-Lussac and the hypothesis of 
 Avogadro, and illustrate each. 
 
 71. Give the principal sources and the chemical and phys- 
 ical properties of the following elements : hydrogen, sulphur, 
 nitrogen, carbon, sodium, and zinc. 
 
 72. How much metallic iron can be obtained by reducing 
 23 g. of ferric oxide ? 
 
 73. If a quantity of steam which, at 100 C. and standard 
 pressure, occupies 500 cc. be cooled to 4 C., what will be 
 the volume of its resulting water ? What will it weigh ? 
 
 74. Give the properties of sodium, potassium, copper, 
 lead, and phosphorus, and the equations for the preparation 
 of each. 
 
 75. Describe the manufacture of white lead, the making 
 of caustic soda, or the refining of copper. 
 
 76. Are the reactions reversible by which () oxygen 
 is obtained from potassium chlorate ? (i) ^hydrogen from 
 sodium and water ? (c) water from oxygen and hydrogen ? 
 Why? 
 
 77. When dilute acid is poured on zinc, what causes the 
 reaction to go in one direction only ? If H dissolved abun- 
 dantly in water, how far would the reaction go ?
 
 92 REVIEW QUESTIONS AND PROBLEMS 
 
 78. Is the burning of a candle a reversible reaction that 
 runs to equilibrium ? Why ? 
 
 79. Thin layers of oxides form over the surfaces of most 
 metals, making soldering impossible. The tinsmith makes 
 firm joints by using acid or rosin when soldering. Explain 
 the action. 
 
 80. Experiments show that 13.1 g. of zinc unite with 32 g. 
 of oxygen to form zinc oxide. Calculate the combining 
 weight of zinc. 
 
 81. Name the following compounds and write the formulas: 
 
 1. The magnesium salt of chloric acid. 
 
 2. The zinc salt of chlorous acid. 
 
 3. The calcium salt of nitrous acid. 
 
 4. The potassium salt of hypochlorous acid. 
 
 5. The sodium salt of carbonic acid. 
 
 6. The lithium salt of perchloric acid. 
 
 7. The mercurous salt of nitric acid. 
 
 8. The mercurous salt of nitrous acid. 
 
 9. The mercuric salt of nitric acid. 
 
 10. The compound of sodium and hydrogen. 
 
 11. The compound of aluminum and silicon. 
 
 12. The two compounds of tin and sulphur. 
 
 82. 1 g. of aluminum acted on by acid yields 1230 cc. of 
 H under standard conditions. Calculate the apparent com- 
 bining weight of Al, and correct this by the use of Dulong 
 and Petit's Law, the specific heat of Al being 0.22. 
 
 83. What is a flame ? What causes the luminosity of a 
 flame ? Why is the Bunsen flame nonluminous ? Describe 
 the structure of the Bunsen flame. 
 
 84. State Avogadro's hypothesis and illustrate it by 
 means of the union of H and to form water, and of Cl 
 and H to form HC1.
 
 MISCELLANEOUS QUESTIONS AND PROBLEMS 93 
 
 85. A solution of potassium permanganate undergoes no 
 change when a current of hydrogen gas is caused to bubble 
 through it. It is soon decolorized, however, after treatment 
 with zinc and sulphuric acid. Explain fully the principle 
 underlying these facts. 
 
 86. What is ozone? How may it be prepared? What are 
 its properties ? What is hydrogen peroxide ? What are its 
 properties ? 
 
 87. What advances of practical importance have resulted 
 from the study of chemistry and from chemical investigation ? 
 
 88. How is ammonia used in refrigeration ? How do you 
 class the radical NH 4 ? 
 
 89. Give the formula and properties of acetylene and 
 describe a method by which it may be made. 
 
 90. The atomic weight of carbon is 12 and of oxygen 
 15.9. What is the weight of 1 1. of a gas of the formula 
 < J 1 ,. < M ),. < '< ), C 2 H 2 ? What volume of will be necessary 
 for the complete combustion of 1 1. of each of these gases ? 
 Give equation in each case. 
 
 91. Give the equations illustrating the formation of H a SO 4 
 from sulphur dioxide, air, steam, and the oxides of nitrogen. 
 State the properties of concentrated sulphuric acid. 
 
 92. A piece of calcium chloride becomes moist after pro- 
 longed exposure to the air. A clear crystal of sodium sul- 
 phate loses its transparency and crumbles to powder after 
 a similar exposure. Explain the principle underlying these 
 facts, and define the terms used to characterize the proper- 
 ties illustrated by them. 
 
 93. Calculate the approximate weight in grams of 1 1. of 
 each of the following gases: HC1, C1 2 , HI, NH 3 . 
 
 94. How may CO 2 be prepared ? Through what cycle does 
 carbon pass in animal and vegetable life?
 
 94 REVIEW QUESTIONS AXD PROBLEMS 
 
 95. Define distillation, filtrate, titration, standard solu- 
 tion, catalysis, indicator, polymerization, alkali, neutral 
 reaction, halogen. 
 
 96. Explain the term " ion " and " ionization." What 
 classes of substances are ionized when dissolved in water ? 
 By what are all such substances designated ? Define acid 
 and base in terms of the theory of electrolytic dissociation. 
 
 97. Write the equation for preparing hydrofluoric acid 
 and explain the process of etching on glass. 
 
 98. Give a brief account of the discovery of any one of 
 the chemical elements, including the name of the discoverer 
 and the approximate date and conditions of discovery. 
 
 99. What is the formula for white arsenic ? What com- 
 pound of arsenic is formed when a solution of the substance 
 is brought together with zinc and sulphuric acid ? Why is 
 the compound not formed when hydrogen gas is led through 
 the. solution ? 
 
 100. In what great industry is calcium phosphate (normal) 
 employed? To what treatment must it first be subjected ? 
 
 101. Name an important ore of lead. Describe a method 
 of extracting lead from the ore mentioned, and mention two 
 practical uses of lead. 
 
 102. Give a brief account of the alkaline-earth metals. 
 Tell how glass is made and colored. 
 
 103. State the general difference between metals and non- 
 metals. What is a heavy metal ? 
 
 104. Is the process of oxidation accompanied by the 
 process of reduction ? Illustrate by an equation and inter- 
 pret. Is occlusion a chemical or a physical action ? State 
 your reasons. 
 
 105. A gas globe when full of air weighed 55.06 g., and 
 when full of water at 20 C. it weighed 309.66 g. The air
 
 MISCELLANEOUS QUESTIONS AND PROBLEMS 95 
 
 was removed from the globe and the latter carefully weighed 
 by means of a counterpoise. The globe was then filled with 
 a gas at 19.8 C. and 761.4mm., when it weighed .469 g. 
 more than when the air was exhausted. What is the weight 
 of a liter of this gas under standard conditions ? 
 
 106. How many cubic centimeters of water will have to 
 be added to 10 g. of H 2 S0 4 to yield a 10 per cent solution 
 of the acid? 
 
 107. What is the heat of formation of sulphuric acid 
 from its elements in a dilute aqueous solution ? 
 
 108. Calculate the percentage composition of garnet 
 (<VV'( Si 4)i); of mica (KH 2 Al 8 (Si0 4 ) 8 ). 
 
 109. How much does a mole of sulphuric acid weigh ? of 
 sodium chloride ? of ammonium nitrate ? 
 
 110. A compound of hydrogen and carbon of exactly the 
 same percentage composition has the gas density of 39. 
 What is its formula? 
 
 111. In the preparation of phosphine what gases may 
 take the place of hydrogen ? 
 
 112. What is a mineral? Are the following substances 
 minerals : quartz, water, granite, mercury, soil, coal oil ? 
 
 113. What other elements besides aluminum act either 
 as acid formers or as base formers ? 
 
 114. What substances must be avoided when galvanized- 
 iron vessels are in use ? 
 
 115. Why is nitric acid a better solvent for Hg, Cu, and 
 Ag than hydrochloric or sulphuric acid ? 
 
 116. A silver dollar contains 10 per cent alloy and weighs 
 26.5 g. How much is the silver in it worth ? How could 
 you separate it from the copper ? 
 
 117. Prove that the phosphorus molecule has 4 atoms.
 
 96 REVIEW QUESTIONS AND PROBLEMS 
 
 118. Reduce the following to the Fahrenheit scale: 
 () + 3oC.; (&) +89C.; (c) - 40 C. ; (d) - 50 C. ; 
 () + 104C. 
 
 119. Reduce the following to the centigrade scale: 
 (a) 38 F.; (ft) 120 F.; (c) - 64 F.; (rf) -30F.; (e) 0F.; 
 (/) - 40 F. 
 
 120. Outline the contact and the lead-chamber processes 
 of manufacturing H 2 S0 4 , and compare them as to efficacy. 
 
 121. Prepare a, table of the halogens according to the 
 following form: 
 
 1. Element. 
 
 2. Atomic weight. 
 
 3. Compounds found in nature (formulas). 
 
 4. Equations for the preparation of the element. 
 
 5. Physical properties. 
 
 6. Chemical properties. 
 
 7. Relative replacing power. 
 
 8. Equations for the preparation of the hydrogen 
 
 compound. 
 
 9. Stability of the hydrogen compound. 
 
 122. What are the speeds of transpiration of ammonia 
 and nitrogen ? 
 
 123. Name three substances one gas, one liquid, and one 
 solid that are used for disinfecting and that have bleach- 
 ing properties. Explain the action of each in bleaching. 
 State the advantage of formaldehyde for fumigation. 
 
 124. In what liquid is sodium usually kept ? How are red 
 and yellow phosphorus usually kept ? Explain. 
 
 125. Give Avogadro's Law and find how many cubic feet 
 of CO are represented in the following reaction if there 
 are represented 10 cu. ft. of C0 2 , all volumes at the same 
 temperature and pressure,
 
 PROBLEMS 97 
 
 CHAPTER XXVI 
 
 PROBLEMS ON MEASUREMENT, TEMPERATURE, 
 WEIGHT, AND DENSITY 
 
 A. MEASUREMENT 
 
 1. Find the number of liters in a cubic meter; the 
 number of cubic millimeters. 
 
 2. How many millimeters in () 16km.? (b) 21Hm.? 
 (c) 26.9m.? (d) 66.92dm.? (e) 108.2cm.? 
 
 3. How many feet in 62.14 m. ? in 390 m. ? 
 
 4. Convert 43 in. into (a) decimeters ; (6) hectometers ; 
 (<;) kilometers ; (</) centimeters ; (e) millimeters. 
 
 5. Calculate the number of liters necessary to fill with 
 water a tank 21 x 60 x 8 ft. in dimension. 
 
 6. Required the number of square millimeters, square 
 centimeters, square decimeters, contained in the top of a 
 flat desk measuring 1 in. 20 cm. by 80 cm. 
 
 7. How many miles in 15km.? 
 
 8. A room 20 m. x 50 m. x 3m. is filled with air under 
 standard conditions. How many liters are there ? How 
 much does it weigh in kilograms ? 
 
 9. A woodpile containing 1500 m. 8 is 12 m. long and 
 12 m. wide. How high is it ? 
 
 10. What is the capacity of a tank in liters that is 
 4 m. x 9 m. x 8 m. in dimension ? 
 
 11. What is the radius in centimeters of a sphere whose 
 volume is measured by 6 1. of water ? 
 
 12. How deep must a cistern be to hold 80001., if the 
 bottom lias a radius of 1.75m.? How deep if it has a 
 square bottom 3m. on a side?
 
 98 REVIEW QUESTIONS AND PROBLEMS 
 
 13. A rectangular scow 40m. long and 7m. wide draws 
 1 in. of water when empty and 3 in. when loaded ; find in 
 kilograms the weight of the load. 
 
 14. How many liters will a cylindrical gasometer 1 in. 
 across and 15 m. high hold ? 
 
 15. A pressure of 1000 Ib. per square inch is how many 
 kilograms per square millimeter ? 
 
 B. TEMPERATURE 
 
 1. Convert into the centigrade scale : 
 (a) 36 R.; (b) 28 R.; (c) 76 R. 
 
 2. Convert into the Reaumur scale : 
 0)90C.; (7)15C.; (c) 55C.; (d) 30 C. 
 
 3. Convert into the Fahrenheit scale : 
 
 (a) 52 R.; (b) 76 R.; (c) 6.7 R.; (d) 25 R. 
 
 4. Convert into the Reaumur scale: 
 
 (a) 48 F.; (b) 129 F.; (c) 210 F.; (d) - 30 F. 
 
 5. Convert into the centigrade scale : 
 
 (a) 207 F.; (ft) 180 F.; (c) 0F. ; (d) -30F. 
 
 6. Convert into the Fahrenheit scale : 
 
 (a) 643 C.; (b) 972 C.; (c) -40C.; (rf) 2500 C. 
 
 7. Convert into the absolute scale : 
 
 (a) 8C.; (b) 40C.; (c) 80C.; (d) 2000F. ; (e) - 37F. 
 
 8. Convert into centigrade, Reaumur, and Fahrenheit 
 
 scales : 
 (a) 400 and (V) 267 absolute scale. 
 
 C. WEIGHT AND DENSITY 
 
 1. How much space will 4320 g. of water occupy ? 
 
 2. What is the weight of water in a tank 20 cm. x 
 31cm. x 92cm.? 
 
 3. A mass of 63 g. is divided into pills 7 in number. 
 What is the weight of each ?
 
 I'KOIJLKMS 99 
 
 4. If a liter of Hg. weighs 13 kg. 598 g., find the weight 
 in kilograms of 4.2 1. 
 
 5. A cubical block of wood 2 cm. on a side weighs 5 g. 
 How far will it sink in alcohol of specific gravity .8 ? 
 
 6. If the density of brass is 8.5, what will be the weight 
 in air of a mass of brass which weighs in vacua 500 g.? 
 
 7. A liter flask weighs 25 g. When filled with a mixture 
 of alcohol and water it weighs 867 g. How many cubic 
 centimeters of each in the flask ? 
 
 8. A piece of cork floats on ether with 12 cc. exposed. 
 What is the entire volume of the cork? 
 
 9. The pressure of the air will hold water 30 ft. high in 
 a vacuum. How high will it hold mercury ? 
 
 10. If a pint of water weighs exactly a pound, how many 
 cubic inches would it contain ? 
 
 11. A lump of metal weighs a ton. Its weight in water 
 is 1500 Ib. What is its specific gravity ? 
 
 12. Find the mass of 50 cc. of benzine if its density = 0.85. 
 
 13. A piece of lead weighed 39.9 g. in air and 36.368 g. 
 in water. What is the specific gravity of lead ? 
 
 14. Find the volume of 1000 g. of sea water. 
 
 15. Find the specific gravity of alcohol from the follow- 
 ing data : 
 
 1. Weight of specific-gravity bottle empty, 20.3920 g. 
 
 2. Weight of specific-gravity bottle filled with water, 
 
 70.3412 g. 
 
 3. Weight of specific-gravity bottle filled with alcohol, 
 
 61.6515 g. 
 
 16. A piece of lead weighs 50 g. in air, and when sus- 
 pended in a liquid whose specific gravity is 1.2 it weighs 
 44.69. Determine the specific gravity of lead.
 
 100 REVIEW QUESTIONS AND PROBLEMS 
 
 17. If sulphuric acid has a specific gravity of 1.84, how 
 many cubic centimeters of it weighs 80 g. ? 
 
 18. Nitric acid is 1.52 times as heavy as water. What is 
 the weight of 3 1. of the acid ? 
 
 19. A balloon contains 1000 cu. m. of a gas whose density 
 is 0.000092 g. per cubic centimeter. Taking the density of 
 air as 0.0003 g. per cubic centimeter, calculate the total 
 weight which the balloon will lift. 
 
 20. A block of wood having a cross section of 
 5 cm. x 4 cm. x 3 cm. floats in water when immersed to a 
 depth of 2.5 cm. What mass of lead on the top would be 
 sufficient to cause complete immersion of the block ? 
 
 21. A piece of metal weighs 50 g. in air, and when sus- 
 pended in a liquid whose specific gravity is 1.2 it weighs 
 44.6 g. What is its specific gravity and what metal is it ? 
 
 22. What is the weight of ammonia and of chlorine 
 necessary to produce 1 1. of nitrogen ? 
 
 23. Calculate the specific heat of iron from the follow- 
 ing data: 
 
 1. Weight of iron used, 100 g. 
 
 2. Weight of ice melted, 14.35 g. 
 
 3. Temperature of the iron at the beginning of the 
 
 operation, 100 C. 
 
 4. Latent heat of water, 80. 
 
 24. How many cubic centimeters of a liquid of specific 
 gravity 1.4 must be mixed with 1 1. of a liquid of specific 
 gravity .8 to make a mixture of specific gravity 1.2 ? 
 
 25. A capillary glass tube weighs .2 g. A thread of mer- 
 cury 12 cm. long is drawn into the tube, when it is found to 
 weigh .7 g. Find the diameter of the capillary tube. 
 
 26. Find the length of an iron rod 2 cm. in diameter 
 that weighs 1 kg.
 
 PROBLEMS 101 
 
 27. If gold were bought in Alaska at a certain price per 
 ounce, and sold in Mexico at the same price, would there be 
 a gain or loss, transportation charges not being considered ? 
 
 28. A quantity of silver when placed in one pan of an 
 untrue balance appeared to weigh 5 gm., but when placed 
 in the other pan 6 gm. What is the true mass of the silver ?
 
 APPENDIX 
 
 CHAPTER XXVII 
 
 I. PHYSICAL CONSTANTS OF THE IMPORTANT 
 ELEMENTS 1 
 
 ELEMENT 
 
 SYMBOL 
 
 ATOMIC 
 WEIGHTS 
 
 VALENCE 
 
 SPECIFIC 
 GRAVITY 
 
 MEI.T- 
 
 PolXT 
 
 BOIL- 
 ING 
 
 POINT 
 
 Ap- 
 
 proxi- 
 mate 
 
 Exact 
 
 Water 
 
 Air 
 
 Aluminum . . 
 
 Al 
 
 27. 
 
 27.1 
 
 III 
 
 2.6 
 
 
 657. 
 
 1500. 
 
 Antimony . . 
 
 si, 
 
 120. 
 
 120.2 
 
 
 6.6 
 
 
 630. 
 
 1500. 
 
 Argon 
 
 A 
 
 40. 
 
 39.9 
 
 
 
 1.38 
 
 -188. 
 
 -186. 
 
 Arsenic 
 
 Aa 
 
 75. 
 
 75. 
 
 III.V 
 
 5.7 
 
 
 
 360. 
 
 Barium .... 
 
 Ba 
 
 137. 
 
 137.4 
 
 II 
 
 3.8 
 
 
 850. 
 
 950. 
 
 Bismuth. . . . 
 
 Bi 
 
 208. 
 
 208. 
 
 III.V 
 
 9.7 
 
 
 269. 
 
 1435. 
 
 Boron 
 
 B 
 
 11. 
 
 11. 
 
 III 
 
 2.6 
 
 
 infus. 
 
 3500. 
 
 Bromine. . . . 
 
 Bi 
 
 80. 
 
 79.96 
 
 I 
 
 3.1 
 
 
 -73 
 
 59. 
 
 Cadmium . . . 
 
 Cd 
 
 112. 
 
 112.4 
 
 II 
 
 8.6 
 
 
 322. 
 
 778. 
 
 Calcium .... 
 
 Ca 
 
 40. 
 
 40.1 
 
 II 
 
 15 
 
 
 800. 
 
 
 Carbon 
 
 C 
 
 12. 
 
 12. 
 
 IV 
 
 1.7-2.1 
 
 
 subl. 
 
 3500. 
 
 Chlorine. . . . 
 
 n 
 
 35.5 
 
 35.45 
 
 I 
 
 
 2.49 
 
 -102. 
 
 -33.6 
 
 Chromium . . 
 
 Or 
 
 52. 
 
 52.1 
 
 II, III, VI 
 
 6.9 
 
 
 1515. 
 
 
 Cobalt 
 
 Co 
 
 59. 
 
 59. 
 
 II 
 
 8.7 
 
 
 1530. 
 
 
 Copper 
 
 Oa 
 
 63.6 
 
 63.6 
 
 1,11 
 
 8.9 
 
 
 1065. 
 
 2100. 
 
 Fluorine. . . . 
 
 F 
 
 19. 
 
 19. 
 
 I 
 
 
 1.31 
 
 -223. 
 
 -187. 
 
 Gold 
 
 Au 
 
 197. 
 
 197.2 
 
 I, III 
 
 19.3 
 
 
 1065. 
 
 
 Helium 
 
 Be 
 
 4. 
 
 4. 
 
 
 
 0.13 
 
 -271. 
 
 -267. 
 
 Hydrogen. . . 
 
 11 
 
 \ 
 
 1.008 
 
 I 
 
 
 0.07 
 
 -256.5 
 
 -2525 
 
 Iodine 
 
 I 
 
 127'. 
 
 126.9 
 
 I 
 
 4.9 
 
 
 114. 
 
 184. 
 
 Iron 
 
 Fe 
 
 56. 
 
 58.9 
 
 n, in 
 
 7.8 
 
 
 1950. 
 
 
 Lead 
 
 Pb 
 
 207 
 
 2069 
 
 II IV 
 
 11.3 
 
 
 327 
 
 1400. 
 
 Lithium .... 
 
 U 
 
 7. 
 
 7.03 
 
 i 
 
 059 
 
 
 186. 
 
 1400. 
 
 Magnesium . 
 
 Mg 
 
 24.3 
 
 24.3 
 
 ii 
 
 1.7 
 
 
 632. 
 
 1100. 
 
 Manganese. . 
 
 Mn 
 
 55. 
 
 55. 
 
 II, IV 
 
 7.4 
 
 
 1245. 
 
 
 Mercury .... 
 
 Kg 
 
 200. 
 
 200. 
 
 1,11 
 
 13.6 
 
 
 -38.8 
 
 357. 
 
 Nickel 
 
 Ni 
 
 58.7 
 
 58.7 
 
 h 
 
 8.7 
 
 
 1484. 
 
 
 Nitrogen . . . 
 
 N 
 
 14. 
 
 
 III.V 
 
 
 0.96 
 
 -210. 
 
 -195. 
 
 Oxygen 
 
 o 
 
 
 ie!oo 
 
 ii 
 
 
 1.10 
 
 -230. 
 
 - 182. 
 
 Phosphorus . 
 Platinum . . . 
 
 p 
 
 rt 
 
 31. 
 195. 
 
 31. 
 
 194.8 
 
 IILV 
 IV 
 
 1.8 
 21.5 
 
 
 44.2 
 1710. 
 
 290. 
 
 Potassium . . 
 
 K 
 
 39. 
 
 39.1 
 
 I 
 
 0.87 
 
 
 625 
 
 757. 
 
 Silicon 
 
 Si 
 
 28. 
 
 28.4 
 
 IV 
 
 2.0 
 
 
 
 3500. 
 
 Silver 
 
 Ag 
 
 108. 
 
 107.9 
 
 I 
 
 105 
 
 
 961. 
 
 2050. 
 
 Sodium .... 
 
 Na 
 
 
 23.05 
 
 I 
 
 057 
 
 
 97.6 
 
 877. 
 
 Strontium . . 
 
 Sr 
 
 8?! 
 
 87.6 
 
 II 
 
 25 
 
 
 900. 
 
 
 Sulphur .... 
 Tin 
 
 S 
 Sn 
 
 33. 
 119. 
 
 32.06 
 119.0 
 
 II, IV, VI 
 
 h,iv 
 
 2.0 
 73 
 
 
 1145 
 232. 
 
 444.6 
 1600. 
 
 Zinc 
 
 /.n 
 
 65. 
 
 65.4 
 
 ii 
 
 7.1 
 
 
 419. 
 
 918. 
 
 1 This table will be found in the text of Brownlee and others, and is used by 
 their permission.
 
 104 REVIEW QUESTIONS AND PROBLEMS 
 
 II. WEIGHTS AND MEASURES 
 
 LENGTH 
 
 1 millimeter (mm.) 
 1 centimeter (cm.) 
 1 decimeter (dm.) 
 1 meter (m.) 
 1 kilometer (km.) 
 
 = 10 mm. 
 = 10 cm. 
 = 10 dm. 
 = 1000 in. 
 
 = 0.03937 inch 
 = 0.3937 inch 
 = 3.937 inches 
 = 39.37 inches 
 = 0.6214 mile 
 
 VOLUME 
 
 1 cubic centimeter (ccm.) = 0.06103 cubic inch 
 
 1 cubic decimeter = 1000 ccm. = 61.03 cubic inches 
 1 liter (1.) =1000ccm. = 1.057 quarts 
 
 1 cubic meter =10001. =35.32 cubic feet 
 
 WEIGHT 
 
 1 milligram (mg.) = 0.0154 grain 
 
 1 gram (g.) = 1000 mg. = 15.432 grains 
 
 1 kilogram (kilo), kg. = 1000 g. = 2.2046 pounds av. 
 
 III. TABLE OF METRIC TRANSFORMATION 
 
 To <:n.\ M; i: 
 
 Inches to centimeters . 
 Centimeters to inches . 
 
 MULTIPLY BY 
 . 2.54 
 0.3937 
 
 Cubic inches to cubic centimeters . . . 16.387 
 
 Cubic centimeters to cubic inches 0.061 
 
 Ounces to grams (avoirdupois) 28.35 
 
 Grams to ounces (avoirdupois) 0.0353 
 
 Grains to grams 0.0648 
 
 Grams to grains 15.43
 
 APPENDIX 
 
 105 
 
 IV. WEIGHT OF ONE LITER OF VARIOUS GASES 
 
 MEASURED UNDER STANDARD 
 
 CONDITIONS 
 
 Air 
 
 . . 1.2023 
 
 Oxygen 
 
 1 430 
 
 Ammonia .... 
 
 . . 0.7(il7 
 
 Hydrogen 
 
 . 0.08984 
 
 Carbon dioxide . . 
 
 . . 1. '.IIJ41 
 
 Hydrosulphuric acid 
 
 . 1.5211 
 
 Carbon monoxide . 
 Chlorine .... 
 Cyanogen . '. . . 
 
 . . 1.251 
 . . 3.1650 
 . . 2.322 
 
 Methane . . . . . 
 Nitric oxide .... 
 Nitrogen 
 
 . 0.7157 
 
 . i.slto 
 
 1 2501 
 
 Ethylene .... 
 
 . . 1.252 
 
 Nitrons oxide . . . 
 
 . 1.9677 
 
 Hydrazoic acid . . 
 Hydrocyanic acid . 
 
 . . 1.920 
 . 1.2036 
 
 Sulphur dioxide . . 
 Steam . 
 
 . 2.8596 
 0.805 
 
 V. PHYSICAL FORMULAS 
 TEMPERATURE 
 
 BOYLE'S AND CHARLES'S LAWS COMBINED 
 
 ()r = 
 
 -a) 
 
 760 [1 + (.003660] 
 
 T'P 
 
 VI. SPECIFIC GRAVITIES 
 
 Brass 
 
 8.4 
 
 Nitric acid 
 
 1 56 
 
 Cork 
 
 0.25 
 
 Silver 
 
 . . 10.5 
 
 Coal 
 
 1.8 
 
 Sulphuric acid . . 
 
 . . 1.84 
 
 Gold 
 
 19.8 
 
 Tin , 
 
 . . 7.3 
 
 Hydrochloric acid . . . 
 
 1.22 
 
 Water (distilli-d) . 
 
 . . 1. 
 
 Iron 
 
 7.8 
 
 Water (sea) ... 
 
 . . 1.025 
 
 Kcrosr-iH' 
 
 0.8 
 
 Water (ice) . . . , 
 
 0.92 
 
 Lead 
 
 11.3 
 
 Zinc 
 
 7.1
 
 106 
 
 REVIEW QUESTIONS AND PROBLEMS 
 
 S3 
 
 2 3
 
 UNIVERSITY OF CALIFORNIA AT LOS ANGELES 
 THE UNIVERSITY LIBRARY 
 
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 MAY 9 
 
 0V 16 1939 
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 JAN 3 1947 
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 MAR 1 7 1943 
 
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