MEDICAL .SCHOOL 
 LUSMAT&lf 
 
 
 
 SIFT OF 
 
 COLLEGE OF PHARMACY 
 
 DEPART Mil 
 
- 
 
 jH : 
 
WORKS OF PROF. A. F. HOLLEMAN, 
 
 Professor Ordinarius in the University of 
 Amsterdam, Netherlands, 
 
 PUBLISHED BY 
 
 JOHN WILEY & SONS, INC. 
 
 A Text-book of Inorganic Chemistry. 
 
 Issued in English in co-operation with HERMON 
 CHARLES COOPER. Fifth English edition, com- 
 pletely revised, viii +521 pp. 6 by 9. 79 figures. 
 Cloth, $2.25 net. 
 
 A Text-Book of Organic Chemistry. 
 
 Edited by A. JAMIESON WALKER, Ph.D., B.A., 
 assisted by OWEN E. MOTT, Ph.D., with the co- 
 operation of the author. Fourth English Edition, 
 partly rewritten. xviii + 621 pp. 6 by 9. 82 
 figures. Cloth, $2.25 net. 
 
 A companion volume to the preceding, and forming 
 with it a comprehensive treatise on pure Chemistry. 
 
 A Laboratory Manual of Organic Chemistry for 
 Beginners. 
 
 An Appendix to the author's Text-book of Organic 
 Chemistry. Edited by A. JAMIESON WALKER, Ph.D., 
 B.A. With the co-operation of the author. Third 
 English Edition, revised, xvii + 83 pp. 5 by 7J. 
 Cloth, $1.00 net. 
 
A 
 LABORATORY MANUAL 
 
 OF 
 
 ORGANIC CHEMISTRY 
 
 FOR BEGINNERS. 
 
 A. F. IIOLLEMAN, PH.D., F.R.A. AMST. 
 
 Professor Ordinarius in the University of Amsterdam. 
 
 AN APPENDIX TO THE AUTHOR'S TEXT-BOOK OF 
 ORGANIC CHEMISTRY 
 
 EDITED BY 
 
 A. JAMIESON WALKER, PH.D., B.A. 
 
 WITH THE CO-OPERATION OF THE AUTHOR. 
 
 THIRD EDITION. 
 TOTAL ISSUE, FIVE THOUSAND. 
 
 College ef Pharmacy 
 
 NEW YORK 
 
 JOHN WILEY & SONS, INC. 
 
 LONDON: CHAPMAN & HALL, LIMITED 
 
 1917 
 
Copyright, 1904, 1913, 
 
 BY 
 
 A. JAMIESON WALKER. 
 
 (First Edition Entered at Stationers 1 Hall.) 
 
 CHRONOLOGICAL SUMMARY. 
 
 ENGLISH EDITIONS. 
 
 First Edition: June, 1904. 
 First Edition, revised: March, 1908. 
 Second Edition: August, 1913. 
 Third Edition: May, 1917. 
 
 The original Dutch edition has also been translated into 
 German, Italian, and Russian. 
 
 PRESS OF 
 
 BRAUNWORTH & CO. 
 
 BOOK MANUFACTURERS 
 
 BROOKLYN. N. Y. 
 
AUTHOR'S PREFACE TO THE THIRD 
 EDITION. 
 
 THE whole of the manual has been carefully revised and 
 some new experiments have been incorporated. Certain 
 obsolete reactions, and others too difficult for the average 
 student, have been omitted. I am again indebted to Dr. 
 JAMIESON WALKER for the care bestowed by him on the 
 revision. 
 
 A. F. HOLLEMAN. 
 
 AMSTERDAM, April, 1917. 
 
 iii 
 
AUTHOR'S PREFACE TO THE REVISED 
 FIRST EDITION. 
 
 IT is admitted universally that chemistry cannot be learnt 
 by the study of text-books only, and that laboratory practice 
 is essential. A student new to the science derives most benefit 
 from a laboratory course of inorganic preparations, simple 
 quantitative experiments, and qualitative inorganic analysis. 
 He is brought thus into contact with work closely connected 
 with the text-books and lectures on this division of chemistry, 
 and is enabled to understand the subject much better than by 
 any other method. 
 
 Formerly, a student beginning the study of organic chemic- 
 try usually had to content himself with text-books and lec- 
 tures, and very seldom had the opportunity of handling the 
 compounds about which he had to read. There was, therefore, 
 an evident lack in the methods of teaching the elements of 
 organic chemistry adopted in the Universities. 
 
 A number of years have elapsed since a course of practical 
 work in organic chemistry was introduced into the Universities 
 of the Netherlands, chiefly through the influence of Professor 
 FRANCHIMONT of Leyden. This laboratory work is a com- 
 plement to the lectures, and has proved very satisfactory. 
 
 At the suggestion of Dr. A. JAMIESON WALKER, the labora- 
 tory manual written by me in Dutch for this purpose is issued 
 now in English. At his request, I have revised the whole 
 
VI AUTHOR'S PREFACE TO REVISED FIRST EDITION 
 
 text, and added some new experiments. In most instances 
 I have indicated the weights or volumes suitable for the reac- 
 tions, an experience of many years having taught me that 
 students always employ much larger quantities than are 
 necessary. The amounts prescribed are approximate, and, 
 to ensure the success of the experiments, need not be weighed 
 or measured with great accuracy. 
 
 It should be mentioned that this manual is related intimately 
 to my text-book of organic chemistry, and constitutes an 
 appendix to it. To obtain the maximum advantage from these 
 experiments, I advise the student first to study them with 
 the aid of the text-book, and afterwards to carry them out 
 in the laboratory. This is the only method by which he can 
 attain to a thorough comprehension of his laboratory work. 
 
 A. F. HOLLEMAN. 
 AMSTERDAM, January, 1908. 
 
EDITOR'S PREFACE TO THE THIRD 
 EDITION. 
 
 THE first English edition of this manual was published 
 in 1904, and a revision was issued in 1908. Owing to the 
 very extensive alterations in the text and in the arrangement 
 of the matter in Professor Holleman's " Text-book of Organic 
 Chemistry " during the preparation of the last two editions, 
 much revision was necessary for the second edition of this 
 volume, published in 1913. For the present issue a certain 
 amount of new matter has been added, and I have to thank 
 Professor Holleman for the time and labour devoted by him 
 to the work. 
 
 It should be noted that the references printed in Clarendon 
 type in the text are to the paragraphs of the fourth edition of 
 Professor Holleman's " Text-book of Organic Chemistry/' 
 and not to those of former editions. 
 
 A. JAMIESON WALKEB. 
 REPTON, DERBY, May, 1917. 
 
 vii 
 
EDITOK'S PEEFACE TO THE REVISED 
 FIRST EDITION 
 
 DURING the time the English edition of Professor HOLLE- 
 MAN'S " Text-book of Organic Chemistry " has been published, 
 it has taken a foremost place among works on the science for 
 students' use. This volume constitutes an appendix to the 
 text-book, and forms an introductory guide to laboratory work 
 in organic chemistry, as well as a compendium of experiments 
 suitable for lecture-table illustration. Its mission is not to 
 displace the standard works on organic preparations, but to 
 supplement them by bridging a gap between theory and prac- 
 tice which they do not, and cannot, span. The text has been 
 brought up to date for the present reprint. 
 
 The translation is from a completely revised and consider- 
 ably extended copy of the Dutch edition, specially prepared 
 by Professor HOLLEMAN for the purpose. To facilitate 
 reference, I have added paragraph headings, and all the 
 manuscript and proof-sheets have been corrected by the 
 author, to whom I am much indebted for his careful revision. 
 
 References in the text printed in Clarendon type are to my 
 translation of Professor HOLLEMAN'S " Leerboek der Organische 
 Chemie," and those to " Inorganic Chemistry " to Dr. COOPER'S 
 translation of his " Leerboek der Anorganische Chemie," 
 published by Messrs. JOHN WILEY and SONS., Inc. 
 
 My thanks are due to the publishers for the care they have 
 bestowed on the production of the work. 
 
 A. JAMIESON WALKER. 
 DERBY, ENGLAND, January, 1908. 
 
 viii 
 
CONTENTS. 
 
 Light figures refer to pages; old-style figures to the author's "Text-book of 
 Organic Chemistry." 
 
 PAGE 
 
 I. QUALITATIVE ANALYSIS OF CARBON COMPOUNDS (3-5) 1 
 
 Detection of Carbon and Hydrogen (3) 1 
 
 Carbonization, 1. Oxidation with copper oxide, 1. 
 Detection of Nitrogen (4) 2 
 
 LASSAIGNE'S method, 2. WILL and VARRENTRAP'S 
 
 method, 2. KJELDAHL'S method, 2. 
 Detection of the Halogens (5) 3 
 
 BEILSTEIN'S test, 3. Calcium-oxide test, 3. 
 Detection of Sulphur (5) 3 
 
 CARIUS'S test, 3. Caustic-alkali test, 3. Ignition with 
 sodium, 4. 
 
 II. THE ALLOTROPIC MODIFICATIONS OF CARBON (16) 4 
 
 Graphite, 4. Wood-charcoal, 4. Bone-charcoal, 4. 
 Decolorization of solutions by bone-charcoal, 4. 
 Absorption of lead salts by bone-charcoal, 5. De- 
 odorizing action of bone-charcoal, 5. 
 
 III. LABORATORY METHODS (17-26) 5 
 
 Fractional distillation, 5. Steam distillation, 6. Ex- 
 traction with solvents, 6. Determination of the melt- 
 ing-point, 6. Determination of the boiling-point, 6. 
 Crystallization, 7. 
 
 IV. SATURATED HYDROCARBONS (28-38) 7 
 
 Preparation of methane, 7. Distillation of petroleum, 
 
 8. Inflammability of petroleum- vapour, 8. Stabil- 
 ity of the saturated hydrocarbons, 8. 
 
 V. ALCOHOLS, C n H 2n -t-i'OH (39-50) 8 
 
 Action of sodium upon alcohol, 8. Fusel oil, 9. Wine, 
 
 9. Heat developed by mixing alcohol and water, 9. 
 Tests for water in alcohol, 9. Separation of water 
 from alcohol, 10. Oxidation of ethyl alcohol, 10. 
 
 ix 
 
x CONTENTS 
 
 PAGB 
 
 VI. ALKTL HALIDES, ESTERS, ETHERS, AND MERCAPTANS (51-60) 10 
 
 Ethyl chloride, 10. Ethylsulphuric acid, 10. Diethyl 
 ether, 11. Ethylmercaptan, 12. 
 
 VII. AMINES AND NITRO-COMPOUNDS (61-70) 12 
 
 Amines (61-67) 12 
 
 Methylamine, 12. Carbylamine-reaction, 12. Mustard- 
 oil reaction, 12. Reaction with copper salts, 13. 
 Nitrous-acid test, 13. Nitrosoamines, 14. Dimethyl- 
 amine and trimethylamine, 14. 
 
 Nitro-compounds (68-70) 14 
 
 Sodium nitromethane, 14. Nitrolic-acid reaction, 14. 
 Reduction of nitro-compounds, 14. 
 
 VIII. NlTRILES AND ISoNlTRILES (76~78) 15 
 
 Preparation, 15. Hydrolysis of nitriles, 15. 
 
 IX. SATURATED ACIDS, C n H 2 nO 2 ; AND ESTERS (79-88; 91-95) 15 
 
 Formic acid, 15. Decomposition of mercuric formate, 
 16. Action of concentrated sulphuric acid on formic 
 acid, 16. Oxidation of formic acid by potassium per- 
 manganate, 17. Cacodyl-test for acetic acid, 17. 
 Stability of acetic acid towards oxidizing agents, 17. 
 Silver acetate, 17. Test for acetic acid, 18. Oxidation 
 of ethyl alcohol to acetic acid, 18. Action of caustic 
 alkalis on sodium acetate, 18. Saponification of butter, 
 
 18. Calcium and lead salts of the higher fatty acids, 19. 
 Volatile fatty acids, 19. Higher fatty acids, 19. Soap, 
 
 19. Emulsifying action of soap, 20. Cleansing action 
 of soap, 20. Ethyl acetate, 20. Velocity of saponifica- 
 tion of ethyl acetate, 20. Solubility of ethyl acetate in 
 water, 20. 
 
 K. ALDEHYDES AND KETONES (98-111) 21 
 
 Aldehydes (98-109) 21 
 
 Acetaldehyde, 21. Silver-mirror test, 21. Aldehyde- 
 resin, 21. SCHIFF'S reaction, 21. Production of 
 formaldehyde, 22. Action of formaldehyde on proteins, 
 22. Non-resinification of formaldehyde, 22. 
 
 Ketones (98-103, 110 and 111) 22 
 
 Acetone, 22. Test for acetone, 22. Addition-product 
 of acetone and sodium hydrogen sulphite, 22. Sepa- 
 ration of acetone from aqueous solution, 23. Oxida- 
 tion of acetone, 23. 
 
CONTENTS 
 
 XI. UNSATUEATED HYDROCARBONS (112-127) . . . 23 
 
 Olefines (112-120) 23 
 
 Ethylene, 23. Luminosity of the ethylene flame, 23. 
 Action of bromine on ethylene, 23. VON BAEYER'S 
 test for the double bond, 24. Explosive mixture of 
 ethylene and oxygen, 24. Unsaturated hydrocarbons 
 in coal gas, 24. Double linking in amylene, 24. 
 
 Acetylene (126) 24 
 
 Preparation of acetylene, 24. Copper acetylene and sil- 
 ver acetylene, 24. 
 
 XII. MONOBASIC UNSATURATED ACIDS (134-138) 25 
 
 Double bond in almond oil, 25. Olei'c acid from almond 
 oil, 25. Elai'dic transformation, 25. Fusion of oleic 
 acid with caustic alkali, 25. Lead oleate, 26. 
 
 XIII. CHLOROFORM AND IODOFORM (144-146) 26 
 
 Preparation of chloroform, 26. Formation of chloroform 
 from trichloroacetic acid, 26. Action of potassium 
 hydroxide on chloroform, 26. Conversion of chloroform 
 into potassium cyanide, 27. Chloroform and silver 
 nitrate, 27. lodoform-test for alcohol, 27. 
 
 XIV. GLYCEROL (151-155) 27 
 
 Preparation of allyl alcohol, 27. Test for glycerol, 28. 
 Action of alkalies on copper salts in presence of 
 glycerol, 28. 
 
 XV. SATURATED DIBASIC ACIDS (161-168) 28 
 
 Oxalic Acid (162) 28 
 
 Preparation of oxalic acid from wood, 28. Conversion 
 of formates into oxalates, 29. Calcium, lead, and cop- 
 per oxalates, 29. Decomposition of calcium oxalate 
 by heat, 29. Decomposition of lead and copper oxa- 
 lates by heat, 29. Action of concentrated sulphuric 
 acid on oxalic acid, 29. Complex oxalates, 30. Action 
 of light on EDER'S solution, 30. Dimethyl oxalate, 30. 
 Diethyl oxalate, 31. Oxamide, 31. 
 
 Succinic Acid (166) 31 
 
 Barium succinate, 31. Basic ferric succinate, 31. Suc- 
 cinimide, 31. 
 
xii CONTENTS 
 
 PAGS3 
 
 XVI. HYDROXY-ACIDS OR ALCOHOL-ACIDS (179-197) 32 
 
 Lactic Acid (182) 32 
 
 Decomposition of lactic acid by dilute sulphuric acid, 32. 
 Decomposition of lactic acid by concentrated sulphuric 
 acid, 32. Oxidation of lactic acid, 32. 
 
 Tartaric Acid (188-196) 32 
 
 Potassium tartrates, 32. Iron ammonium tartrate, 32. 
 FEHLING'S solution, 33. Action of heat on tartaric 
 acid, 33. Microchemical test for tartaric acid and race- 
 mica cid, 33. Relative solubility of calcium tartrate 
 and calcium racemate, 33. " Tartar emetic," 33. 
 
 Citric Acid (197) 33 
 
 Preparation from lemons, 33. Action of concentrated 
 sulphuric acid on citric acid, 34. 
 
 XVII. CHLORAL HYDRATE (201) 34 
 
 Action of water on chloral, 34. Action of alkali hydroxide 
 on chloral hydrate, 34. Silver-mirror test for chloral 
 hydrate, 35. Action of sodium hydrogen sulphite on 
 chloral hydrate, 35. 
 
 XVIII. ALDEHYDO-ALCOHOLS AND KETO-ALCOHOLS OR SUGARS (202- 
 
 228) 35 
 
 Properties of the Monoses (203) 35 
 
 Silver-mirror test, 35. Resinification with caustic alkalies, 
 35._Reduction of FEHLING'S solution, 35. Osazones, 35. 
 
 Methods of Formation of the Monoses (206) 36 
 
 Inversion of sucrose (cane-sugar), 36. Glycerose, 36. 
 
 Pentoses (207) 36 
 
 Furfuraldehyde-test, 36. 
 
 Hexoses (208) 3 6 
 
 Hydrochloric-acid test, 36. 
 
 Dextrose (208) 37 
 
 Calcium alkoxide of dextrose, 37. Glucosesulphuric acid, 
 37. Copper alkoxide of dextrose, 37. Detection of 
 dextrose in urine, 37. Oxidation of dextrose by nitric 
 acid, 37. 
 
 La3vulose (209) 38 
 
 Alcoholic character, 38. Test for bevulose, 38. 
 
 d-Galactose (211) 38 
 
 Oxidation of d-galactose to mucic acid, 38. 
 
CONTENTS 
 
 Hexodioses (213-220) 38 
 
 Lactose (215) 8 
 
 Detection of lactose in milk, 38. Lactosazone, 39. 
 " Sand-sugar," 39. 
 
 Sucrose (216-220) 39 
 
 Properties distinguishing sucrose from the monoses, 39. 
 Action of heat on sucrose, 39. Tricalcium saccharate, 
 
 39. Inversion, 39. 
 
 Polyoses (224-228) 40 
 
 Starch (225 and 226) 40 
 
 Starch-paste, 40. Properties distinguishing starch from 
 the monoses, 40. Conversion of starch into dextrose, 
 
 40. Iodine-test for starch, 40. Barium alkoxide of 
 starch, 40. Conversion of starch into dextrin, 40. 
 Potato-starch, 41. 
 
 Cellulose (227 and 228) 41 
 
 Hydrolysis of cellulose, 41. Parchment-paper, 41. 
 Solubility of cellulose in SCHWEITZER'S reagent, 41. 
 Nitrocelluloses, 41. Detection of lignin in paper, 42. 
 
 XIX. PROTEINS (246-254) 42 
 
 Detection of nitrogen and sulphur in the proteins, 42. 
 " Salting-out " proteins with ammonium sulphate, 42. 
 Coagulation of proteins by alcohol, 42. Coagulation 
 of proteins by nitric acid, 43. Biuret-reaction, 43. 
 MILLON'S reagent, 43. Xanthoprotein-reaction, 43. 
 ADAMKIEWICZ'S reaction, 43. Decomposition-products 
 of keratin, 43. 
 
 XX. HYDROCYANIC ACID AND ITS SIMPLE AND COMPLEX SALTS (256 
 
 and 257) 43 
 
 Hydrocyanic acid, 43. Prussian-blue test, 44. Silver 
 cyanide, 44. Hydrolysis of potassium cyanide, 44. 
 Conversion of ammonium formate into hydrocyanic 
 acid, 44. Double ferrocyanide of potassium and cal- 
 cium, 44. Ferrocyanic acid, 44. Action of concen- 
 trated sulphuric acid on potassium ferrocyanide, 44. 
 Action of heat on potassium ferrocyanide, 45. Potas- 
 sium ferricyanide, 45. Reduction of potassium ferri- 
 cyanide, 45. Oxidation of potassium ferrocyanide by 
 potassium permanganate, 45. 
 
xiv CONTENTS 
 
 PAGE 
 
 XXI. POTASSIUM CYANATE AND POTASSIUM THIOCYANATE (258-260). . 45 
 
 Potassium cyanate, 45. Potassium thiocyanate, 46. 
 Silver thiocyanate, 46. 
 
 XXII. DERIVATIVES OF CARBONIC ACID (263-270) 46 
 
 Carbon Disulphide (264) 46 
 
 Inflammability, 46. Volatility, 46. Solvent power, 46. 
 Barium trithiocarbonate, 47. Potassium and copper 
 salts of xanthic acid, 47. 
 Urea (266 and 267) 47 
 
 WOHLER'S synthesis, 47. Urea oxalate, 47. Urea 
 nitrate from urine, 47. KNOP'S method for the esti- 
 mation of urea in urine, 48. BUNSEN'S method for 
 the estimation of urea in urine, 48. LIEBIG'S method 
 for the estimation of urea in urine, 48. Action of heat 
 on urea, 48. Cyanuric acid, 48. 
 Carbamic Acid (268) 49 
 
 Calcium carbamate, 49. Ammonium dithiocarbamate, 49. 
 
 XXIII. URIC ACID GROUP (271-273) , 49 
 
 Ammonium urate, 49. Di-potassium urate, 49. Mu- 
 rexide-test for uric acid, 49. Reduction of silver 
 nitrate by uric acid, 50. Murexide-test for caffeine, 50. 
 
 XXIV. BENZENE AND ITS HOMOLOGUES (281-288) 50 
 
 Stability of benzene towards the halogens, 50. Absence 
 of double bonds in benzene, 50. Nitrobenzene, 50. 
 Benzenemonosulphonic acid. 50. FRIEDEL and CRAFTS'S 
 reaction, 51. Formation of benzene from calcium ben- 
 zoate, 51. Oxidation of side-chains, 51. 
 
 XXV. MONOHALOGEN COMPOUNDS (289) 51 
 
 Stability of monochlorobenzene towards alcoholic potash 
 or soda, 51. 
 
 XXVI. MONOHYDRIC PHENOLS (292-294) 52 
 
 Preparation of phenol from calcium salicylate, 52. Prep- 
 aration of phenol by fusion of sodium benzenesulphonate 
 with sodium hydroxide, 52. Sodium phenoxide, 52. 
 Tribromophenol, 52. Ferric-chloride test for phenol, 
 52. Depression of the freezing-point of phenol, 53. 
 Action of nitric acid on phenol, 53, Cresol, 53. 
 
CONTENTS xv 
 
 PAGB 
 
 XXVII. MONOAMINO-COMPOUNDS AND THEIR DERIVATIVES (296-301) . 53 
 
 Aniline, 53. Neutral reaction of aniline, 54. Aniline 
 salts, 54. Tribromoaniline, 54. Bleaching-powder test 
 for aniline, 54. Potassium-dichromate test for ani- 
 line, 54. Acetoanilide, 54. Carbylamine-reaction, 54. 
 Diphenylamine, 54. Nitrosodimethylaniline, 55. 
 LIEBERM ANN'S test for aromatic nitroso-compounds, 
 
 55. Azobenzene, hydrazobenzene, and benzidine sul- 
 phate, 55. Diphenylurea, 55. 
 
 XXVIII. DlAZO-COMPOUNDS AND HYDRAZINES (305-310) 56 
 
 Benzenediazonium chloride, 56. Replacement of Nz- 
 group in benzenediazonium chloride by hydroxyl, 
 
 56. GATTERMANN'S reaction, 56. Diazoaminobenzene, 
 56. Aminoazobenzene, 56. Oxidation of phenylhy- 
 drazine by FEHLING'S solution, 57. 
 
 XXIX. BENZOIC ACID AND ITS DERIVATIVES (311-313) 57 
 
 Benzonitrile and benzoic acid, 57. Benzo'ic acid from 
 gum-benzoin, 57. Volatility of benzoic acid with steam, 
 
 58. Solubility of benzoic acid in water, 58. Ethyl 
 benzoate, 58. Benzanilide, 58. Benzamide, 58. 
 
 XXX. BENZALDEHYDE (314 and 315) 59 
 
 Silver-mirror test, 59. Benzaldehydephenylhydrazone, 
 
 59. Sulphite compound of benzaldehyde, 59. Action 
 of alcoholic potash on benzaldehyde, 59. Oxidation of 
 benzaldehyde, 59. 
 
 XXXI. BENZENE HOMOLOGUES WITH SUBSTITUTED SIDE-CHAINS (321- 
 
 325) 60 
 
 Saponification of benzyl chloride by potassium or sodium 
 hydroxide, 60. Benzyl iodide, 60. Action of light on 
 toluene in presence of bromine, 60. Resinification of 
 benzyl alcohol, 60. 
 
 XXXII. COMPOUNDS CONTAINING AN UNSATURATED SIDE-CHAIN (328) 61 
 
 Oxidation of cinnamic acid by potassium permanganate, 61. 
 
 XXXIII. POLYSUBSTITUTED BENZENE DERIVATIVES (329-350) 61 
 
 Reactivity of the halogen atom in halogen nitro-com- 
 pounds, 61. m-Dinitrobenzene, 61. Reactivity of 
 one nitro-group in 1 : 3 : 5-trinitrobenzene, 61. Nitro- 
 
XVI CONTENTS 
 
 phenols, 62. Coloured salts of p-nitrophenol, 62. Picric 
 acid, 62. Potassium picrate, 62. Taste of picric acid, 
 62. Dyeing with picric acid, 62. isoPurpuric acid, 
 
 62. Chloropicrin, 62. lonization of picric acid in 
 aqueous solution, 63. Tests for catechol, resorcinol, and 
 quinol, 63. Reducing power of the dihydroxybenzenes, 
 
 63. Pyrogallol, .63. Benzoquinone, 64. Quinhy drone, 
 
 64. Difference in basicity of the three nitroanilines, 64. 
 Reactivity of the amino-group in picramide, 64. p-Dia- 
 zobenzenesulphonic acid, 64. Oxidation of amino- 
 phenols, 64. Test for nitrous acid with ra-phenylenedia- 
 mine, 64. Dyeing with aminoazobenzene, 65. Reduc- 
 tion of aminoazobenzene, 65. Taste of " saccharin," 
 
 65. Salicylic acid, 65. Action of bromine- water on 
 salicylic acid, 65. Identification of salicylic acid and 
 phenol, 65. Calcium salicylate, 65. Manufacture of 
 ink, 65. Action of tannin on gelatin, 66. Test for 
 tannin, 66. Action of tannin on quinine, 66. Inter- 
 action of proteins and tannin, 66. Decomposition of 
 anthranilic acid, 66. Phthalic anhydride, 66. Fluor- 
 escein, 66. Phenolphthalein, 66. Red anion of 
 phenolphthalein, 67. 
 
 XXXIV. HYDROCYLIC COMPOUNDS (365-370) 67 
 
 Artificial camphor, 67. Volatility of camphor with 
 steam, 67. Camphor and water, 67. Camphoric 
 acid, 67. 
 
 XXXV. BENZENE-NUCLEI LINKED TOGETHER BY CARBON (371-374) . . 68 
 
 Rosolic acid, 68. Magenta, 68. Action of concen- 
 trated hydrochloric acid on a solution of magenta, 68. 
 Colour-base, 68. Leu co-base, 68. 
 
 XXXVI. CONDENSED BENZENE-NUCLEI (377-386) 69 
 
 Action of heat on naphthalene, 69. Naphthalene 
 picrate, 69. Naphthalenemonosulphonic acids, 69. 
 a-Nitronaphthalene, 69. Crude naphthol, 69. Mar- 
 tius's yellow, 70. Naphthylamines, 70. Congo-red, 70. 
 Naphthionic acid, 70. Oxidation of anthracene by chro- 
 mic acid, 70. Test for anthraquinone, 70. Potas- 
 sium salt of alizarin, 70. 
 
CONTENTS 
 
 xvii 
 
 XXXVII. HETEROCYCLIC COMPOUNDS (387-399) 71 
 
 Pyridine, 71. Action of pyridine on ferric chloride, 71. 
 Action of pyridine on mercuric chloride, 71. Test for 
 pyridine, 71. Action of the alkaloid-reagents on pyri- 
 dine, 71. Stability of pyridine towards VON BAEYER'S 
 reagent, 71. Stability of pyridine towards oxidizing 
 agents, 71. Pyrrole-red, 71. Indophenin-reaction, 71. 
 Tests for antipyrine, 72. 
 
 XXXVIII. CONDENSATION-PRODUCTS OF BENZENE AND HETEROCYLIC 
 
 NUCLEI (400-405) 72 
 
 SKRAUP'S synthesis of quinoline, 72. Quinoline hydro- 
 chloride, 72. Quinoline picrate, 72. Quinoline di- 
 chromate, 73. Volatility of indigo, 73. Solubility of 
 indigo in nitrobenzene, 73. Indigosulphonic acid, 73. 
 Oxidation of indigo to isatin, 73. "Vat-dyeing," 73. 
 
 XXXIX. ALKALOIDS (406-415) 73 
 
 Alkaloid-reagents, 73. Nicotine, 73. Fluorescence of 
 quinine-sulphate solution, 74. Action of chlorine on 
 quinine salts, 74. Test for strychnine, 74. Test for 
 brucine, 74. 
 
 INDEX 75 
 
A LABORATORY MANUAL OF 
 ORGANIC CHEMISTRY. 
 
 I. QUALITATIVE ANALYSIS OF CARBON COMPOUNDS. 
 
 (3-5.) 
 DETECTION OF CARBON AND HYDROGEN (3). 
 
 1. Carbonization. A small quantity of sugar is heated in a 
 crucible covered with a lid. Inflammable gases are evolved, 
 leaving a residue of charcoal. This is proved to be carbon 
 by heating it in a hard-glass tube about 15 cm. long sealed 
 at one end, and slightly inclined, the tube being first filled 
 with oxygen, and closed with a loosely-fitting cork. Car- 
 bon dioxide is formed, part remaining in the tube. After 
 cooling, lime-water is agitated with the gas, and becomes 
 turbid owing to the formation of calcium carbonate, CaCOs. 
 
 The presence of carbon in coal-gas is shown by the soot 
 deposited when a cold surface, such as that of a porcelain 
 crucible-lid, is introduced into a luminous flame. 
 
 2. Oxidation with Copper Oxide. 10 g. of finely-powdered 
 copper oxide a hygroscopic substance are dried by heat- 
 ing in a dish or crucible. While still warm it is mixed care- 
 fully with a small quantity of sugar, and the mixture placed 
 in a hard-glass tube sealed at one end; the open end of the 
 tube is then closed with a cork, and a delivery-tube leading 
 into lime-water. On heating, the sugar is oxidized by the 
 
2 LABORATORY MANUAL OF ORGANIC CHEMISTRY [i. 
 
 copper oxide; the carbon dioxide evolved makes the lime- 
 water turbid, and the water formed condenses in drops on the 
 cool part of the tube. 
 
 DETECTION OF NITROGEN (4). 
 
 3. a) LASSAIGNE'S Method. A piece of dried albumin a 
 substance containing nitrogen and a piece of sodium are 
 placed in a narrow tube sealed at one end. The tube is then 
 gradually heated to redness, and maintained at this tem- 
 perature for a few minutes. The hot end of the tube is placed 
 in 2-3 c.c. of water, whereupon it cracks, and the sodium 
 cyanide formed dissolves. After filtering through a small 
 filter-paper, and washing the residue with a few drops of 
 water, a drop of a solution containing iron in the ferrous and 
 ferric state is added to the filtrate, and the mixture acidified 
 slightly with hydrochloric acid to dissolve the precipitated fer- 
 rous and ferric hydroxides. If sodium cyanide was present, 
 there remains a blue precipitate, due to the formation of 
 Prussian blue. 
 
 6) WILL and VARRENTRAP'S Method. Small pieces of dry 
 albumin are mixed with five times their bulk of soda-lime, and 
 the mixture warmed in a test-tube. A strip of moist, red 
 litmus-paper held at the open end of the tube is turned blue by 
 the evolved ammonia, and the characteristic odour of the 
 gas can also be detected. 
 
 c) KJELDAHL'S Method. 0- 1 g. of acetamide is heated with 
 2 c.c. of concentrated sulphuric acid in a test-tube. After a 
 short interval, the reaction-mixture is poured carefully into 
 25 c.c. of water, excess of sodium hydroxide added, and the 
 beaker covered with a glass plate having a moistened strip of 
 red litmus-paper adhering to its lower surface. In a few 
 minutes the litmus is turned blue by the evolved ammonia. 
 
i.] QUALITATIVE ANALYSIS OF CARBON COMPOUNDS 3 
 DETECTION OF THE HALOGENS (5). 
 
 4. a) BEILSTEIN'S Test. Copper oxide is introduced into 
 a loop at the end of a piece of platinum-wire by dipping the 
 moistened loop into finely-powdered copper oxide, heating 
 in the flame, and repeating these operations several times. 
 A piece of copper-oxide wire held by the platinum-wire can 
 also be used. The copper oxide is then heated to redness 
 until the flame is no longer coloured, cooled, moistened with a 
 drop of chloroform, CHCls, by the aid of a capillary pipette, 
 and again introduced into the flame. The vapour of the copper 
 halide (chloride) formed imparts a fine green colour to the flame. 
 
 6) Calcium-oxide Test. A lump of quicklime is heated in a 
 test-tube to a high temperature, and, while still hot, two drops 
 of chloroform are added. When cold, the contents of the 
 tube are treated with water, and the lime dissolved by dilute 
 nitric acid free from hydrochloric acid. On addition of silver 
 nitrate to this solution, a precipitate of silver chloride is 
 obtained, proving the presence of chlorine iir the chloroform. 
 
 Chloroform is agitated with silver-nitrate solution, but 
 no precipitate of silver chloride is formed. 
 
 DETECTION OF SULPHUR (5). 
 
 5. a) CARIUS'S Test. 0*1 g. of ammonium thiocyanate, 
 NHUCNS, is warmed with 5 c.c. of nitric acid of 1*2 specific 
 gravity till the reaction begins; to prevent the oxidation be- 
 coming too violent, the heating is then discontinued. After 
 dilution of the cold solution with 25 c.c. of water, barium 
 chloride is added, the resulting white precipitate of barium 
 sulphate indicating that the sulphur has been oxidized to 
 sulphuric acid. 
 
 6) Caustic-alkali Test. A small quantity of egg-albumin 
 is warmed with a concentrated solution of sodium hydroxide 
 (1 : 2), in which it dissolves, forming sodium sulphide among 
 the products. This can be proved either by adding a few 
 
4 LABORATORY MANUAL OF ORGANIC CHEMISTRY [n. 
 
 drops of lead acetate, resulting in the formation of black lead 
 sulphide, PbS; or by bringing a drop of the liquid into con- 
 tact with a bright silver coin, with production of a brownish- 
 black stain of silver sulphide, Ag2S; or by addition of two 
 or three drops of a solution of sodium nitroprusside to the 
 alkaline mixture, when a deep-violet coloration results, some 
 minutes elapsing before the colour attains its maximum 
 intensity. Traces of sulphur can be detected by this reaction, 
 c) Ignition with Sodium. A piece of albumin is ignited 
 with sodium as described in 3, a, and the hot tube placed in 
 water. After filtration, the presence of sodium sulphide in 
 the solution can be detected by means of lead acetate or 
 sodium nitroprusside (5, b). 
 
 II. THE ALLOTROPIC MODIFICATIONS OF CARBON. 
 
 (16.) 
 
 1. Graphite. 0*1 g. of graphite is mixed with 5 g. of 
 finely-powdered copper oxide, and heated to a high tem- 
 perature in the apparatus described in I., 2. The evolved 
 carbon dioxide renders the lime-water turbid. 
 
 2. Wood-charcoal. A piece of wood-charcoal is gently 
 heated in a test-tube; the water occluded in the pores of the 
 charcoal 'evaporates, and condenses in drops on the cool parts 
 of the tube. 
 
 A piece of wood-charcoal is placed in water, and the mixture 
 warmed. The air present in the pores of the charcoal escapes, 
 forming bubtles in the water. 
 
 3. Bone-charcoal. Pieces of bone are placed in a crucible 
 fitted with a lid, and heated in a fume-cupboard. Vapours of 
 disagreeable odour are evolved, the residue in the crucible 
 consisting of bone-charcoal and the mineral constituents of 
 the bones. The bone-ash is freed from mineral matter by 
 heating the residue with hydrochloric acid. 
 
 4. Decolorization of Solutions by Bone-charcoal. 20 c.c. of 
 a very dilute solution of magenta a red dye are agitated 
 
in.] LABORATORY METHODS 5 
 
 with a teaspoonful of bone-charcoal, and filtered. The filtrate 
 is colourless (" Inorganic Chemistry/' 176). 
 
 5. Absorption of Lead Salts by Bone-charcoal. 20 c.c. of a 
 very dilute solution of lead acetate are tested for lead by 
 addition of an aqueous solution of hydrogen sulphide. The 
 solution must be so dilute that it gives a brown turbidity, 
 but no precipitate. 
 
 A like volume of the lead-acetate solution is agitated for a 
 short time with a teaspoonful of bone-charcoal, and then 
 filtered. On addition of hydrogen sulphide solution, no 
 turbidity or brown coloration is developed in the filtrate (" In- 
 organic Chemistry," 176). 
 
 6. Deodorizing Action of Bone-charcoal. A dilute aqueous 
 solution of hydrogen sulphide, having a perceptible odour 
 of the gas, is agitated with bone-charcoal, and filtered. An 
 odourless filtrate is obtained. 
 
 III. LABORATORY METHODS. 
 (17-26.) 
 
 i. Fractional Distillation. 50 c.c. of 90 per cent, alcohol 
 diluted with 50 c.c. of water are placed in a 100 c.c. fraction- 
 ating-flask fitted with a thermometer and connected with a 
 condenser, and gently heated with a small flame. The liquid 
 begins to boil about 78, and the distillate is collected in two 
 fractions, the first passing over below 88, and the second 
 above that temperature. After the distillation is complete 
 the first fraction is returned to the flask, and slowly distilled 
 till the thermometer again reaches 88. The burner is then 
 removed, the second fraction poured back into the flask, 
 and the distillation continued without changing the receiver 
 till the temperature has again risen to 88. A different 
 receiver is now employed, and the process continued till dis- 
 tillation is complete. 
 
 The first fraction contains most of the alcohol, and can be 
 ignited; the second is chiefly water, and is incombustible. 
 
6 LABORATORY MANUAL OF ORGANIC CHEMISTRY [m. 
 
 2. Steam Distillation. 10 c.c. of petroleum are placed in a 
 200-c.c. flask d (22, Fig. 17) connected with a condenser. 
 Water is boiled in the can a, which is fitted with a safety- 
 tube b and a delivery-tube c, the evolved steam being passed 
 into the flask d through a glass tube reaching to the bottom, 
 and bent as in the illustration. The flask is inclined at an 
 angle to prevent the petroleum being carried over mechanically. 
 The distillate is a mixture of petroleum and water. 
 
 3. Extraction with Solvents. 10 c.c. of a five per cent, 
 solution of urea and 10 c.c. of ether are introduced into a sepa- 
 rating-funnel, and the mixture vigorously shaken. When the 
 liquid has separated into two layers, these are removed, and 
 each is evaporated to dryness in a porcelain dish on the water- 
 bath. Only a trace of urea is obtained from the ether, this 
 substance being very soluble in water, and almost insoluble 
 in ether. 
 
 A saturated solution of salicylic acid is prepared by vigor- 
 ously agitating 1 g. of the acid with 25 c.c. of water, and filter- 
 ing. The filtrate is extracted with 10 c.c. of ether as described 
 in the last paragraph. Almost all the salicylic acid dissolves 
 in the ether, being very soluble in this solvent, and but slightly 
 soluble in water. 
 
 4. Determination of the Melting-point. A little naphthalene 
 is placed in a narrow glass tube sealed at one end, several 
 of these being obtained by drawing out a test-tube. The 
 capillary tube is fastened with an india-rubber ring to the 
 stem of a thermometer, so that the part containing the naphtha- 
 lene is about half-way up the mercury bulb. The end of the 
 thermometer carrying the tube is then immersed in a melting- 
 point flask or beaker containing water, which is slowly heated 
 with a small flame. When the substance melts, the tem- 
 perature (80) of the thermometer is observed. 
 
 5. Determination of the Boiling-point. A small quantity 
 of benzene is placed in a fractionating-flask having a high 
 side-tube connected with a condenser. The flask is closed with 
 
iv.] SATURATED HYDROCARBONS 7 
 
 a cork fitted with a thermometer, the bulb being placed sev- 
 eral centimetres below the side-tube. The benzene is heated 
 with a small flame to ebullition, and the temperature at 
 which the mercury becomes stationary noted. This is the 
 boiling-point. 
 
 6. Crystallization. 3 g. of crude oxalic acid are dissolved 
 in 10 c.c. of hot water, and the impurities present in the acid 
 removed by filtering the turbid solution. On standing, the 
 clear filtrate deposits crystals of oxalic acid. The mother- 
 liquor is poured off, the crystals are drained on a funnel, and 
 dried on a porous plate or between sheets of filter-paper. 
 
 IV. SATURATED HYDROCARBONS. 
 (28-38.) 
 
 i. Preparation of Methane, CH4. 5 g. of aluminium carbide 
 are placed in a fractionating-flask, and covered with 100 c.c. 
 of water. The mouth of the flask is then closed with a cork, 
 and the methane evolved through the side-tube collected 
 in thick-walled cylinders. One of these cylinders is closed 
 with a glass plate, and turned mouth upwards. On removal 
 of the cover, and ignition of the gas with a burner or taper, 
 it burns with a flame of feeble luminosity. When combus- 
 tion ceases, some lime-water is poured quickly into the cylinder, 
 the cover replaced, and the contents agitated. The carbon 
 dioxide formed by the combustion of the gas renders the lime- 
 water turbid. 
 
 A thick-walled explosion-cylinder is filled about one-third 
 full with methane, and the remainder with oxygen. On igni- 
 tion, the mixture explodes with a loud report. 
 
 A cylinder is filled with chlorine by downward displace- 
 ment, and over it is placed an inverted cylinder full of methane, 
 closed with a glass plate. The plate is removed, and the gases 
 mixed by inverting the cylinders several times, care being taken 
 
8 LABORATORY MANUAL OF ORGANIC CHEMISTRY [v. 
 
 to prevent loss. After insertion of two glass plates between 
 the cylinders, one is placed mouth downwards in a saturated 
 solution of common salt, and the cover removed. In diffused 
 daylight the liquid slowly rises, the colour of the chlorine dis- 
 appears, and oily drops of the substitution-products methyl- 
 ene chloride, CH^Ck; chloroform, CHCls; and carbon tetra- 
 chloride, CCU are deposited on the sides of the cylinder. 
 The mixture must not be exposed to direct sunlight, or there is 
 danger of an explosion. On ignition of the contents of the 
 other cylinder, hydrochloric acid is produced, and soot de- 
 posited. 
 
 2. Distillation of Petroleum. Petroleum is distilled g lowly 
 from a flask connected with a condenser and fitted v/ith a 
 thermometer. The boiling-point rises gradually, proving the 
 liquid to be a mixture. 
 
 3. Inflammability of Petroleum- vapour. 5 c.c. of petroleum 
 are poured into a porcelain dish. A lighted match plunged 
 into the liquid is extinguished. If, however, the petroleum 
 is carefully heated to 40 on a water-bath, the inflammable 
 vapour evolved is ignited by the application of a burning 
 match. 
 
 4. Stability of the Saturated Hydrocarbons. Samples of 
 petroleum and of paraffin-wax are agitated with concentrated 
 sulphuric acid and with concentrated nitric acid. Being 
 mixtures of saturated hydrocarbons, they are neither acted 
 on nor dissolved. 
 
 V. ALCOHOLS, C n H 2n+1 - OH. 
 (39-50.) 
 
 i. Action of Sodium upon Alcohol. 0-5 g. of sodium is intro- 
 duced into a small fractionating-flask containing 10 c.c. of 
 absolute alcohol, and fitted with a delivery-tube for collecting 
 gas over water. The mouth of the flask is immediately closed 
 
v.] ALCOHOLS, CnH 2 n+i-OH 9 
 
 with a cork, and an energetic evolution of gas takes place. 
 The gas is collected in a cylinder, and proved by ignition to be 
 hydrogen. 
 
 2. Fusel-oil. A small quantity of crude spirit is evaporated 
 slowly on a water-bath. After the volatilization of the ethyl 
 alcohol, the odour of fusel-oil is very marked. , It is also per- 
 ceptible when a few drops of the spirit are placed on the palm 
 of the hand, and rubbed with the finger to promote the evapo- 
 ration of the ethyl alcohol. 
 
 3. Wine. 25 c.c. of wine contained in a fractionating- 
 flask connected with a condenser are heated on a water-bath. 
 Alcohol distils, and can be recognized by its odour and 
 inflammability. 
 
 4. Heat Developed by Mixing Alcohol and Water. 10 c.c. 
 of absolute alcohol and 10 c.c. of water are poured into two 
 small beakers, and these immersed in a large vessel of water 
 to bring them to the same temperature. This is noted, and 
 after removal of the beakers from the water their contents 
 are mixed quickly and stirred with the thermometer. A rise 
 in temperature is observed. 
 
 5. Tests for Water in Alcohol. a) Copper-sulphate Test. 
 3 g. of blue crystallized copper sulphate, CuS04,5H2O, are 
 gently heated in a porcelain crucible till anhydrous, the salt 
 being converted into a white powder. When cold, the residue 
 is transferred to a test-tube or small flask containing 15 c.c. 
 of aqueous alcohol; the copper sulphate soon regains its original 
 blue colour, on account of the formation of the hydrated salt, 
 CuS0 4 ,5H 2 0. 
 
 6) CRISMER'S Test. 2 c.c. of petroleum are added to a 
 like volume of alcohol of about 90 per cent, strength, and a 
 thermometer is introduced into the liquid. At first, the two 
 liquids do not mix completely, but the application of slight 
 heat renders them wholly miscible. The liquid is allowed 
 to cool, and the temperature is noted at the moment of 
 appearance of turbidity. One drop of water is then added, 
 
10 LABORATORY MANUAL OF ORGANIC CHEMISTRY [vi. 
 
 and the liquid again heated until it becomes homogeneous. 
 On cooling, turbidity reappears at a temperature some degrees 
 higher than on the first occasion. 
 
 6. Separation of Water from Alcohol. Alcohol of about 50 
 per cent, strength is agitated with solid potassium carbonate, 
 and, if enough of the salt has been added, two layers are 
 obtained. These are separated by means of a tap-funnel. 
 The upper layer is strong alcohol, and burns on ignition; the 
 lower layer is a concentrated, aqueous solution of potassium 
 carbonate, containing only a trace of alcohol. 
 
 7. Oxidation of Ethyl Alcohol. Ethyl alcohol is heated with 
 an aqueous solution of potassium permanganate until the 
 violet colour has disappeared and manganese dioxide has been 
 precipitated. On acidifying the mixture with sulphuric acid 
 and distilling, an acid distillate with an odour of acetic acid is 
 obtained. 
 
 The iodoform-test for ethyl alcohol is given in XIII., 6; 
 the benzoate-test in XXIX., 5. 
 
 VI. ALKYL HALIDES, ESTERS, ETHERS, AND MER- 
 
 CAPTANS. 
 
 (51-60.) 
 
 1. Ethyl Chloride. A mixture of 10 c.c. of alcohol and 5 c.c. 
 of concentrated sulphuric acid is added to 5 g. of common salt 
 contained in a 50-c.c. fractionating-flask connected with a 
 condenser in a fume-cupboard. On warming, gaseous ethyl 
 chloride, C2H5C1, is evolved, and dissolves in the condensed 
 alcohol. When ignited, this distillate burns with a green- 
 tinged flame a phenomenon characteristic of many chlorine 
 derivatives. 
 
 2. Ethylsulphuric Acid. About 2 c.c. of concentrated sul- 
 phuric acid are poured carefully into an equal volume of absolute 
 alcohol, the mixing being accompanied by rise of temperature. 
 
vi.] ALKYL HALIDES, ESTERS, ETHERS, ETC. 11 
 
 The mixture is heated gently for a short time, cooled, and poured 
 into 25 c.c. of water. This solution is stirred, and barium 
 carbonate added till the liquid is no longer acid to litmus. 
 Carbon dioxide is evolved, with formation of insoluble barium 
 sulphate and soluble barium ethylsulphate, Ba^HsSO^. 
 After filtering, dilute sulphuric acid is added to a portion of 
 the filtrate; the precipitate of barium sulphate formed proves 
 the presence of a barium salt in solution. 
 
 On warming the rest of the filtrate with dilute hydrochloric 
 acid, barium sulphate is precipitated. This is due to the 
 decomposition of the liberated ethylsulphuric acid into alcohol 
 and sulphuric acid, followed by the interaction of the latter 
 with the barium ions present in the solution. 
 
 3. Diethyl Ether, (C2H5)2O. A fractionating-flask is fitted 
 with a cork carrying a tap-funnel and a thermometer, both 
 arranged nearly to touch the bottom. After 50 c.c. of alcohol 
 of ninety per cent, strength and 50 c.c. of concentrated sul- 
 phuric acid have been poured into the flask, 5 g. of anhydrous 
 aluminium sulphate are added, and the flask is connected to 
 a condenser with a rapid current of water flowing through its 
 jacket. Heat is then applied till the thermometer indicates 
 a temperature between 130 and 140. As soon as the dis- 
 tillation of ether begins, alcohol is introduced slowly into the 
 flask from the tap-funnel, and the distillation continued with a 
 small flame so as to maintain the temperature constant. The 
 distillate is agitated in a separating-funnel with a like volume 
 of w r ater, which dissolves most of the alcohol, leaving a layer 
 of ether floating on the surface of the solution. After separa- 
 tion from the aqueous liquid, the ether is dried by agitation 
 for a few minutes with fused and finely-powdered calcium 
 chloride. 
 
 A small quantity of the ether is agitated with a large excess 
 of water, in which it dissolves. 
 
 A mixture of 5 c.c. of ether and 5 c.c. of water is shaken in a 
 separating-funnel, and the ethereal and aqueous layers sepa- 
 
12 LABORATORY MANUAL OF ORGANIC CHEMISTRY [vn. 
 
 rated carefully. Anhydrous copper sulphate added to this 
 ether turns blue, proving that the ether has dissolved some of 
 the water. On gently warming the aqueous layer in a por- 
 celain dish, ether-vapour is evolved, and can be recognized 
 by its odour and by its combustion with a bright, luminous 
 flame. This proves that the water has dissolved some of the 
 ether. 
 
 The absorption of heat caused by the evaporation of ether 
 can be demonstrated by placing a small quantity in the palm of 
 the hand, and blowing on it. A sensation of cold is felt imme- 
 diately. 
 
 4. Ethylmercaptan. On warming 2 c.c. of a saturated 
 solution of potassium ethylsulphate with a like volume of a 
 thirty-three per cent, solution of potassium hydrogen sul- 
 phide, KHS, the odour of ethylmercaptan at once becomes 
 perceptible. 
 
 VII. AMINES AND NITRO-COMPOUNDS. 
 (61-70.) 
 
 AMINES (61-67). 
 
 1. Methylamine. A thin paste of bleaching-powder is ren- 
 dered strongly alkaline by addition of slaked lime, and mixed 
 with an aqueous solution of 5 g. of acetamide, CH3-CONH2. 
 On distillation, an aqueous solution of methylamine, CH 3 'NH 2 , 
 is obtained (259). 
 
 2. Carbylamine-Reaction. A portion of the solution thus 
 obtained is warmed gently with one or two drops of chloroform 
 and a small quantity of alcoholic potash. Owing to the forma- 
 tion of methylcarbylamine, CHs-NC, the odour characteristic 
 of i'sonitriles is perceived (77). 
 
 3. Mustard-oil Reaction. A mixture of carbon disulphide 
 and absolute alcohol in like proportions is added to another 
 
VII.] 
 
 AMINES AND NITRO-COMPOUNDS 
 
 13 
 
 portion of the distillate obtained in i, till solution is com- 
 plete, and the liquid is warmed for a short time. On addi- 
 tion of ferric chloride, a black precipitate of sulphide of iron is 
 formed; and, on further heating, the odour of .methyl-mustard- 
 oil, CH 3 'NCS, becomes perceptible (260). 
 
 4. Reaction with Copper Salts. The remainder of the dis- 
 tillate of i is added drop by drop to 1 c.c. of a dilute solution 
 of copper sulphate. At first a precipitate of copper hydroxide 
 is formed, and on further addition of the amine-solution redis- 
 solves, with production of a deep-blue colour. The reaction, 
 therefore, is analogous to that between ammonium hydroxide 
 and copper salts (" Inorganic Chemistry/' 244). 
 
 5. Nitrous-acid Test. A concentrated aqueous solution of 
 1 g. of ethylamine hydrochloride, C2H5NH2,HC1, and 1 g. of 
 
 NITROUS ACID TEST FOR PRIMARY AMINES. 
 
 potassium or sodium nitrite is poured slowly through a thistle- 
 funnel into a 50-c.c. fractionating-flask a, containing 20 c.c. 
 of glacial acetic acid (Fig.). The evolved nitrogen is freed 
 from ethyl nitrite by passing it through a small wash-bottle 
 6, containing alcoholic potash. The gas is collected over water 
 in a cylinder c, and proved to be nitrogen by its extinguishing 
 a lighted wood-splint or taper. By means of the iodoform- 
 
14 LABORATORY MANUAL OF ORGANIC CHEMISTRY [vn. 
 
 test (XIII., 6), the presence of alcohol in the fractionating- 
 flask can be shown. 
 
 6. Nitrosoamines. To a cold, saturated, aqueous solution of 
 1 g. of potassium or sodium nitrite is added 1 g. of solid diethyl- 
 amine hydrochloride, (C2H5) 2 NH,HC1, and one drop of dilute 
 sulphuric acid. On gently heating the liquid, diethylnitroso- 
 amine, (X^Hs^N-NO, collects on the surface as a yellow oil 
 of characteristic odour. 
 
 7. Dimethylamine and Trimethylamine. A small quantity of 
 sodium-hydroxide solution is added to herring-brine contained 
 in a distilling-flask connected with a condenser. On heating, a 
 distillate is obtained; this is alkaline, owing to the presence of 
 dimethylamine and trimethylamine. Like ammonium hydrox- 
 ide, it precipitates ferric hydroxide, Fe203,nH20, from a solu- 
 tion of ferric chloride. 
 
 NITRO-COMPOUNDS (68-70.) 
 
 1. Sodium Nitromethane. A solution of 3 drops of nitro< 
 methane in 1 c.c. of absolute alcohol is prepared. To this are 
 added a few drops of a solution of sodium ethoxide, obtained 
 by dissolving small pieces of sodium in 10 c.c. of absolute 
 alcohol. The white precipitate of sodium nitromethane is 
 filtered off, and, while still moist, is dissolved in a small 
 quantity of water. It must not be dried or a dangerous explo- 
 sion may result. When moist, it is innocuous. 
 
 2. Nitrolic-acid Reaction. The liquid thus obtained is 
 mixed with a few drops of a concentrated aqueous solution of 
 sodium nitrite, and carefully acidified with dilute sulphuric 
 acid. The blood-red colour of the sodium salt of methyl- 
 nitrolic acid is produced. It is discharged by adding more 
 acid, but returns on addition of a dilute solution of sodium 
 hydroxide. 
 
 3. Reduction of Nitro-compounds. 3 drops of nitromethane 
 are added to potassium-hydroxide solution and granulated 
 
UULLtGt 
 
 of PHARMACY 
 
 ix.] SATURATED ACIDS, CnH 2 nO 2 ; AND ESTERS 15 
 
 zinc contained in a test-tube. The characteristic odour of 
 methylamine at once becomes perceptible, and a strip of red 
 litmus-paper held in the vapour is turned blue. 
 
 VIII. NITRILES AND zsoNITRILES. 
 
 (76-78.) 
 
 1. Preparation. A mixture of 10 g. 01 potassium ethyl- 
 sulphate and 10 g. of dried potassium ferrocyanide is sub- 
 mitted to dry distillation in a retort connected with a con- 
 denser. The distillate has the isonitrile odour, due to the 
 presence of ethylcarbylamine. Agitation with dilute sulphuric 
 acid for a short time removes this smell, whereupon that of 
 the nitrile propionitrile formed in the reaction becomes 
 perceptible, although it was previously wholly masked by that 
 of the isonitrile, a by-product. 
 
 2. Hydrolysis of Nitrile s. The liquid of i is made alkaline 
 with potassium hydroxide, and boiled in a test-tube. The 
 evolution of alkaline vapours can be detected by means of 
 a strip of moistened, red litmus-paper. 
 
 The reaction-mixture contains potassium propionate. On 
 acidifying with dilute sulphuric acid and distilling, propionic 
 acid passes over, the distillate turning blue litmus red. 
 
 IX. SATURATED ACIDS, C n H 2n O 2 ; AND ESTERS. 
 (79-88; 91-95.) 
 
 i. Formic Acid. A mixture of 10 g. of glycerol and 10 g. of 
 crystallized oxalic acid is heated in a fractionating-flask con- 
 nected with a condenser. Carbon dioxide is evolved, as can be 
 demonstrated by holding a test-tube containing lime-water at 
 the outlet of the condenser so that the gas enters the tube. 
 After an energetic evolution of gas has continued for some time, 
 
16 LABORATORY MANUAL OF ORGANIC CHEMISTRY [ix. 
 
 5 g. of crystallized oxalic acid are added, and the heating 
 renewed. Formic acid distils (153). 
 
 2. Decomposition of Mercuric Formate. A portion of the 
 distillate of i is agitated with a small quantity of finely-divided 
 mercuric oxide, prepared by triturating the powder in a mortar 
 with a little water. The resulting solution of mercuric for- 
 mate is filtered from the excess of mercuric oxide, and heated. 
 At first, carbon dioxide is evolved, and white mercurous for- 
 mate precipitated. On further heating, the mercurous salt is 
 decomposed with evolution of carbon dioxide, and precipita- 
 tion of metallic mercury: 
 
 TT 
 
 H gOOCH + C0 2 + HCOOH; 
 
 Mercurous 
 
 Mercuric formate formate 
 
 Hg|OOCH+H|COQ|Hg = 2Hg + C0 2 + HCOOH. 
 
 Mercurous formate 
 
 The liquid now contains free formic acid, and, therefore, 
 turns blue litmus red. It is filtered, and the filtrate is neu- 
 tralized exactly with sodium or ammonium hydroxide; on 
 addition of silver-nitrate solution, silver formate is precipitated. 
 When this is heated, it decomposes with evolution of carbon 
 dioxide, liberating half the formic acid and precipitating metallic 
 silver, analogously to the mercury salt. The reaction of the 
 liquid, therefore, again becomes acid. 
 
 3. Action of Concentrated Sulphuric Acid on Formic Acid. 
 Another portion of the distillate of i is placed in a sir all flask, 
 and kept cool during the slow addition of twice its volume of 
 sulphuric acid. The flask is closed with a cork and delivery- 
 tube, the end of the latter dipping under water in a pneumatic 
 trough. On the application of heat, a gas is evolved. It is 
 collected in a cylinder, and, on ignition, burns with the blue 
 flame characteristic of carbon monoxide. Agitation of the 
 contents of the cylinder with lime-water produces turbidity, 
 proving the formation of carbon dioxide by the combustion. 
 
rx.] SATURATED ACIDS, CnH 2 nO2; AND ESTERS 17 
 
 4. Oxidation of Formic Acid by Potassium Permanganate. 
 
 The remainder of the formic acid obtained in i is heated with a 
 small quantity of potassium permanganate and dilute sulphuric 
 acid in the apparatus employed in 3, the end of the delivery- 
 tube being immersed in lime-water contained in a test-tube. 
 The permanganate solution is decolorized, and the carbon 
 dioxide produced by the oxidation of the formic acid renders 
 the lime-water turbid. 
 
 5. Cacodyl-Test for Acetic Acid. On distilling sour beer 
 (200 c.c.), an acid distillate is obtained with an odour of acetic 
 acid. The distillate is nearly neutralized with a few drops of 
 sodium-hydroxide solution, a slightly acid reaction being 
 maintained. It is then evaporated, the last traces of water 
 being removed by heating over a free flame. A portion of 
 the anhydrous sodium acetate thus obtained is mixed with 
 arsenious oxide, and the mixture heated gently in a test- 
 tube. The excessively disagreeable odour of cacodyl oxide, 
 (CH 3 )2As As(CHs) 2 , is soon perceived (73). This sub- 
 stance being extremely poisonouSj great care must be exercised 
 in carrying out the experiment, and the heating should be dis- 
 continued as soon as the odour has been detected. 
 
 6. Stability of Acetic Acid towards Oxidizing Agents. Small 
 quantities of dilute potassium-permanganate solution and 
 dilute sulphuric acid are added to 5 drops of acetic acid. 
 Unlike formic acid, the acetic acid does not decolorize the 
 permanganate solution. 
 
 7. Silver Acetate. 1 g. of sodium acetate is dissolved in 
 10 c.c. of water, and a solution of silver nitrate added. The 
 precipitate of silver acetate, which is only slightly soluble in 
 water at the ordinary temperature, is collected on a filter, and 
 sufficient to saturate the aqueous solution at the boiling-point 
 transferred to a beaker containing 50 c.c. of boiling, distilled 
 water. On cooling, the salt crystallizes in long, silky needles. 
 These are filtered off, spread on a porous plate to remove as 
 much of the mother-liquor as possible, and dried in a dish on 
 
18 LABORATORY MANUAL OF ORGANIC CHEMISTRY [ix 
 
 the water-bath. On carefully heating the salt in a porce- 
 lain crucible, it decomposes, leaving a residue of metallic 
 silver. 
 
 8. Test fdr Acetic Acid. A few drops of ferric chloride are 
 added to a dilute solution of sodium acetate. Owing to the 
 formation of a complex aceto-ferric acetate, the liquid turns 
 blood-red. On boiling this solution, a reddish-brown, flocculent 
 precipitate of basic acetate of iron is formed. If allowed to 
 stand for a short time, this sinks to the bottom of the test- 
 tube, leaving the supernatant liquid colourless. 
 
 9. Oxidation of Ethyl Alcohol to Acetic Acid. A mixture of 
 6 g. of potassium dichromate and 10 g. of concentrated sulphuric 
 acid is introduced into a 100-c.c. distilling-flask connected 
 with a condenser, and a solution of 2 c.c. of alcohol in 10 c.c. 
 of water added drop by drop from a tap-funnel. On heating, 
 acetic acid distils, and can be recognized by its odour, or, after 
 careful neutralization with sodium carbonate, by the ferric- 
 chloride test (8). 
 
 10. Action of Caustic Alkalis on Sodium Acetate. One part 
 by weight of sodium acetate, which has been fused and finely 
 powdered, is thoroughly mixed with four parts by weight of 
 soda-lime. The mixture is heated in a hard-glass retort of 
 100 c.c. capacity, fitted with a delivery-tube for collecting the 
 gas in cylinders over water. The gas is collected in a thick- 
 walled cylinder and ignited (IV., i). 
 
 Methane thus prepared always contains some hydrogen, 
 and to obtain a product of maximum purity, it is best to 
 keep the temperature as low as possible. 
 
 11. Saponification of Butter. About 5 g. of butter are 
 saponified by boiling in a porcelain dish with 20 c.c. of a 
 solution of 1 part of sodium hydroxide in 2 parts of water, 
 the mixture being constantly stirred. After a few minutes, 
 it begins to foam. The heating is continued for twenty 
 minutes, and the contents of the dish allowed to cool. The 
 liquid separates into two layers the lower an aqueous 
 
ix.] SATURATED ACIDS, CnH 2 nO 2 ; AND ESTERS 19 
 
 solution of glycerol and sodium hydroxide, and the upper 
 the fused sodium salts of the fatty acids, which are insoluble 
 in concentrated sodium-hydroxide solution. When cold, the 
 upper layer is semi-solid. It is separated from the aqueous 
 solution, and dissolved in water to free it from unsaponified 
 fat. This can be almost completely removed by filtration 
 through a moistened filter-paper. 
 
 12. Calcium and Lead Salts of the Higher Fatty Acids. A 
 part of the soap solution obtained by the method described 
 in ii is neutralized with dilute acetic acid, and calcium chloride 
 and lead acetate respectively (idded to separate portions. Pre- 
 cipitates of the calcium and lead salts of the higher fatty acids 
 are formed. 
 
 13. Volatile Fatty Acids. The rest of the soap solution is 
 poured into a 100-c.c. distilling-flask connected with a condenser, 
 and excess of dilute sulphuric acid added. On heating, water 
 and the volatile fatty acids of the butter distil, chief of the latter 
 being ?i-butyric acid. They can be detected by their odour 
 and acid reaction. 
 
 14. Higher Fatty Acids. After the distillation of the vola- 
 tile fatty acids, the residue in the flask consists of the solid 
 higher fatty acids. It is transferred to a porcelain dish, allowed 
 to cool, and the solid layer of fatty acids triturated with 
 water several times to remove adhering sulphuric acid. To 
 prove that the mixture has an acid reaction, it is dissolved in 
 alcohol, and the solution added drop by drop to a very dilute 
 solution of sodium hydroxide coloured red by a drop of phenol- 
 phthale'in. The colour disappears, and the acids dissolve, 
 proving that the alkali has been neutralized. 
 
 15. Soap. A few drops of an alcoholic solution of phenol- 
 phthalein are added to a concentrated, neutral soap solution. 
 On dilution with a large excess of water, the colourless liquid 
 becomes red, owing to the liberation of free alkali by the 
 hydrolytic dissociation of the salts of the fatty acids. 
 
 A solution of calcium sulphate is added to one of soap, 
 
20 LABORATORY MANUAL OF ORGANIC CHEMISTRY [ix. 
 
 whereupon the calcium salts of the higher fatty acids are pre- 
 cipitated. 
 
 16. Emulsifying Action of Soap. About 2 g. of soap are 
 dissolved in sufficient water to render the solution alkaline, 
 a few drops of oil are added, and the solution vigorously 
 agitated. An emulsion is produced. 
 
 17. Cleansing Action of Soap. A mixture of soot and 
 water is decanted into a filter. The filter-paper is then removed 
 from the funnel, refolded with the black surface outward, and 
 replaced in the funnel. Water poured into the reversed 
 filter remains clear during percolation; but filtration of a soap- 
 solution renders it black, and cleanses the paper completely. 
 
 1 8. Ethyl Acetate. Dry hydrochloric-acid gas is passed 
 into a mixture of 10 c.c. of glacial acetic acid and 15 c.c. of 90 
 per cent alcohol. The gas can be prepared by gently heating 
 dried common salt with concentrated sulphuric acid in a flask, 
 or can be obtained from a KIPP generator charged with lump 
 ammonium chloride and concentrated sulphuric acid. The 
 mixture is heated for an hour under a reflux-condenser, and 
 then poured into brine. Drops of ethyl acetate separate, 
 a liquid characterized by its pleasant and refreshing odour. 
 
 19. Velocity of Saponification of Ethyl Acetate. A small 
 quantity of ethyl acetate is dissolved in water, and like 
 volumes of the solution transferred to two test-tubes fitted 
 with corks. One portion is agitated with a few drops of 
 potassium or. sodium hydroxide, and the other with a like 
 volume of dilute sulphuric acid. Since the saponification is 
 effected much more rapidly by the caustic alkali than by the 
 acid, the odour of the ester vanishes from the first tube much 
 sooner than from the second. 
 
 20. Solubility of Ethyl Acetate in Water. An excess of 
 ethyl acetate is vigorously agitated with 25 c.c. of water at 
 the ordinary temperature till saturation is complete, and the 
 aqueous solution is separated from the undissolved ester. 
 When warmed, the solution becomes turbid from the separa- 
 
x.] ALDEHYDES AND KETONES 21 
 
 tion of ethyl acetate, which is more soluble in cold than in hot 
 water. 
 
 X. ALDEHYDES AND KETONES. 
 (98-111.) 
 
 ALDEHYDES (98-109). 
 
 1. Acetaldehyde. A mixture of 60 g. of water, 20 g. of 
 concentrated sulphuric acid, and 15 g. of ninety per cent, 
 alcohol is added to 13 g. of potassium dichromate contained 
 in a 200-c.c. fractionating-flask connected with a condenser. 
 Sometimes the oxidation begins spontaneously; should it 
 not, however, the flask is gently heated on a sand-bath, with 
 a rapid current of cold water flowing through the condenser. 
 A mixture of water, alcohol, acetaldehyde, and acetal distils, 
 and can be used in carrying out the aldehyde-reactions 
 described in 2, 3, and 4. 
 
 2. Silver-mirror Test. A small portion of the distillate is 
 diluted with water in a clean test-tube, and a few drops of an 
 ammoniacal silver solution added. This is prepared by 
 adding a small excess of a solution of sodium hydroxide to 
 one of silver nitrate, and then ammonium hydroxide drop by 
 drop in exactly sufficient quantity to redissolve the precipitate. 
 After being shaken, the test-tube is immersed in water heated 
 almost to its boiling-point. If the tube is thoroughly clean, 
 the reduced silver is deposited on its sides as a mirror; if not, 
 a black precipitate of the metal is obtained. 
 
 3. Aldehyde-resin. Potassium hydroxide is added to another 
 portion of the distillate, and the mixture warmed. A yellow 
 coloration is produced at once, and, on further heating, a 
 precipitate of aldehyde-resin is formed. 
 
 4. SCHIFF'S Reaction. Another portion of the distillate 
 is added to a solution of magenta decolorized with sulphurous 
 acid SCHIFF'S reagent. The red colour of the dye is restored. 
 
22 LABORATORY MANUAL OF ORGANIC CHEMISTRY [x. 
 
 5. Production of Formaldehyde. A red-hot copper spiral 
 is placed in a test-tube containing 1 c.c. of methyl alcohol, 
 and a cork is loosely inserted in the mouth of the tube. When 
 cold, the spiral is removed, and the presence of formaldehyde 
 detected by the reduction of FEHLING'S solution (XVI., 6). 
 
 6. Action of Formalin on Proteins. The yolk of an egg 
 is carefully placed in formalin. After the lapse of some time, 
 it will be found to have acquired the consistency of an india- 
 rubber ball. 
 
 7. Non-re sinification of Formaldehyde. A few drops of 
 formalin are diluted with water, and a solution of sodium 
 hydroxide added. Heating the liquid produces no resinification. 
 
 KETONES (98-103, 110 and 111). 
 
 8. Acetone. About 50 g. of dried calcium acetate are 
 heated to a high temperature in a retort connected with a 
 condenser. Acetone is the principal constituent of the dis- 
 tillate, to which the by-products present impart an empyreuma- 
 tic odour. On addition of water, most of the liquid dissolves; 
 the insoluble tar-like products are separated by filtration 
 through a moistened filter-paper. 
 
 9. Test for Acetone. The filtrate obtained in 8 is added 
 to a solution of mercuric nitrate made strongly alkaline by 
 addition of alcoholic potash. On agitating the mixture, the 
 acetone dissolves a part of the mercuric oxide suspended in 
 the liquid. By repeated filtration, a clear filtrate is obtained. 
 On addition of ammonium sulphide to this, a precipitate 
 of mercuric sulphide is formed, proving the presence of mer- 
 cury in the solution. 
 
 10. Addition-product of Acetone and Sodium Hydrogen Sul- 
 phite. 5 c.c. of acetone are agitated with a like volume of a 
 very concentrated solution of sodium hydrogen sulphite; a 
 crystalline addition-product is precipitated, being almost 
 insoluble in the concentrated sulphite solution. On addi- 
 tion of water, it dissolves. 
 
xi.] UNSATURATED HYDROCARBONS 23 
 
 11. Separation of Acetone from Aqueous Solution. 5 c.c. of 
 acetone are added to a like volume of water, with which the 
 ketone is miscible in all proportions. On addition of solid 
 potassium hydroxide to the mixture till saturation is complete, 
 the liquid separates into two layers, the upper one being 
 chiefly acetone, and the lower an aqueous solution of potassium 
 hydroxide containing traces of acetone. 
 
 12. Oxidation of Acetone. An aqueous solution of 2 c.c. of 
 acetone is prepared, and a dilute solution of potassium per- 
 manganate added till the pink colour of the liquid persists. 
 After removal of the manganese dioxide by filtration, the 
 filtrate is acidified with dilute sulphuric acid and distilled^ 
 After careful neutralization with sodium carbonate, the 
 presence of acetic acid in the distillate can be proved by the 
 ferric-chloride test (IX., 8). 
 
 XI. UNSATURATED HYDROCARBONS. 
 
 (112-127.) 
 OLEFINES (112-120). 
 
 1. Ethylene. A mixture of 20 c.c. of alcohol of eighty per 
 cent, strength and 120 c.c. of concentrated sulphuric acid is 
 allowed to stand for some time. It is then heated in a large 
 flask on a sand-bath, the tendency to foam being checked by 
 the addition of 7 g. of anhydrous aluminium sulphate, or a 
 quantity of sand. The ethylene evolved is collected over 
 water in cylinders, being thereby freed from most of the car- 
 bon dioxide and sulphur dioxide generated along with it. 
 
 2. Luminosity of the Ethylene Flame. One of the cylin- 
 ders is turned mouth upwards, and its contents ignited; the 
 ethylene burns with a luminous flame. 
 
 3. Action of Bromine on Ethylene. A small quantity of 
 bromine-water is added to another cylinder, the open end 
 closed with a glass plate, and the contents agitated. The 
 
24 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xi. 
 
 red colour is discharged, and oily drops of ethylene bromide, 
 C2H 4 Br 2 , collect on the sides of the cylinder, the character- 
 istic odour of this compound also becoming perceptible. 
 
 4. VON BAEYER'S Test for the Double Bond. The gas in a 
 third cylinder is shaken up with mixed aqueous solutions of 
 potassium permanganate and sodium carbonate. The violet 
 colour of the solution is discharged, and a brown precipitate 
 of hydrated manganese dioxide, MnCb/ftH^O, formed. 
 
 5. Explosive Mixture of Ethylene and Oxygen. A thick- 
 walled cylinder one-quarter full of ethylene is filled up with 
 oxygen, the contents mixed by shaking, and a light applied. 
 The mixture explodes with a loud report. 
 
 6. Unsaturated Hydrocarbons in Coal-gas. Two cylinders 
 are filled with coal-gas by displacement of water. By the 
 application of the tests described in 3 and 4, the gas can be 
 shown to contain unsaturated compounds. 
 
 7. Double Linking in Amylene. The presence of a double 
 linking in amylene can be demonstrated by the reactions 
 described in 3 and 4. 
 
 ACETYLENE (126). 
 
 8. Preparation of Acetylene. A piece of calcium carbide 
 is dropped into water contained in a 100-c.c. fractionating- 
 flask fitted with a delivery-tube dipping under water, and the 
 neck of the flask quickly closed with a cork. A vigorous 
 evolution of acetylene ensues. The gas is collected in cylin- 
 ders, and submitted to the tests described in 2, 3, and 4. 
 
 9. Copper Acetylene and Silver Acetylene. An ammoniacal 
 solution of cuprous chloride is prepared by adding ammonium 
 hydroxide to a mixture of cuprous chloride and water till solu- 
 tion is complete. On addition of a portion of this liquid to a 
 cylinder containing acetylene a red precipitate of copper acety- 
 lene is formed, readily soluble in hydrochloric acid with evolu- 
 tion of acetylene. 
 
 An ammoniacal silver solution prepared by adding ammo- 
 
xii.] MONOBASIC UNSATURATED ACIDS 25 
 
 nium hydroxide carefully to a solution of silver nitrate till the 
 precipitate first formed has just redissolved gives with 
 acetylene a white precipitate of silver acetylene. 
 
 XII. MONOBASIC UNSATURATED ACIDS. 
 (134-138.) 
 
 1. Double Bond in Almond Oil. 5 c.c. of almond oil, con- 
 sisting principally of glyceryl oleate, are diluted with 10 c.c. 
 of ether or carbon disulphide. A portion of the solution is 
 agitated with bromine-water; the colour is discharged. To 
 another portion is added a solution of potassium permanganate 
 and sodium carbonate; a brown precipitate of hydrated man- 
 ganese dioxide is obtained. 
 
 2. Oleic Acid from Almond Oil. 5 c.c. of almond oil are 
 saponified by the method described in IX., n, the heating 
 with sodium hydroxide being continued for not less than an 
 hour. Periodically, water is added to replace that lost by 
 evaporation. The resulting sodium-soap is dissolved in water 
 and the solution acidified with dilute sulphuric acid. The 
 liberated oleic acid forms a liquid layer on the surface of the 
 aqueous solution, from which it is removed by the aid of a 
 separating-funnel. The tests for double linkings described 
 in XI., 3 and 4, are carried out with portions of this acid. 
 
 3. Elaidic Transformation. Some of the liquid oleic acid is 
 poured into 2 or 3 c.c. of a concentrated solution of sodium 
 nitrite, a small quantity of dilute sulphuric acid added, and 
 the mixture allowed to stand for some time. Owing to 
 its transformation into elai'dic acid, the liquid oleic acid 
 gradually becomes solid. 
 
 4. Fusion of Oleic Acid with Caustic Alkali. 5 g. of sodium 
 hydroxide are heated to fusion with a few drops of water in an 
 iron crucible, and 2 c.c. of olei'c acid added. The mixture is 
 stirred, and maintained for some time in the fused state. 
 
26 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xm. 
 
 After cooling, it is dissolved in water, and excess of dilute 
 sulphuric acid added. On distillation from a fractionating- 
 flask, an acid distillate is obtained, containing acetic acid. 
 
 5. Lead Oleate. 5 c.c. of almond oil, 25 c.c. of water, 
 and 10 g. of lead monoxide are boiled in a porcelain dish, 
 with constant stirring, until the red colour of the lead 
 oxide has disappeared. The operation requires at least an hour. 
 Water is added periodically to replace that lost by evapora- 
 tion. After cooling, the water is poured off, and the plaster- 
 like lead oleate (so-called " lead-plaster ") formed is triturated 
 thoroughly with ether by the aid of a pestle. After filtering, 
 and distilling the ether, the lea-d oleate is left in the semi-solid 
 state. Addition of hydrogen-sulphide solution proves the 
 presence of lead, a black precipitate of lead sulphide being 
 produced. 
 
 XIII. CHLOROFORM AND IODOFORM. 
 
 (144-146.) 
 
 1. Preparation of Chloroform. 25 g. of fresh bleaching- 
 powder, 10 c.c. of alcohol of eighty-five per cent, strength, and 
 10 c.c. of water are heated gently in a litre flask on a sand- 
 bath till the reaction begins; the flame is then removed. 
 There is much foaming, and water and chloroform distil, the 
 latter constituting the lower layer of the distillate. 
 
 2. Formation of Chloroform from Trichloroacetic Acid. An 
 aqueous solution of 1 g. of trichloroacetic acid is boiled in a 
 fractionating-flask. Carbon dioxide is evolved, and can be 
 identified by its action on lime-water. When the mixture 
 has cooled, the presence of chloroform in the flask can be 
 detected by the odour. 
 
 3. Action of Potassium Hydroxide on Chloroform. A few 
 drops of chloroform are heated in a test-tube with a small 
 quantity of dilute potassium hydroxide, potassium chloride 
 
xiv.] GLYCEROL 27 
 
 and potassium formate being produced. The mixture is 
 neutralized so as to maintain a slightly alkaline reaction, 
 and heated with a solution of mercuric chloride. Reduction 
 to mercurous chloride, and then to metallic mercury, proves 
 the presence of dissolved formate (IX., 2). 
 
 4. Conversion of Chloroform into Potassium Cyanide. 1 c.c. 
 of chloroform is heated in a test-tube for a short time with 
 5 c.c. of concentrated alcoholic ammonia and 1 c.c. of con- 
 centrated alcoholic potash. The liquid is transferred to a 
 porcelain dish, and evaporated to dryness on a water-bath. 
 The presence of potassium cyanide in the residue is detected 
 by the method employed in LASSAIGNE'S test for nitrogen 
 (I., 3 a). 
 
 5. Chloroform and Silver Nitrate. 1 c.c. of chloroform is 
 agitated three or four times with water in a test-tube, using 
 about 10 c.c. for each operation; traces of hydrochloric acid, 
 if present, are thus eliminated. More water and 2 or 3 drops 
 of silver-nitrate solution are then added. A precipitate of 
 silver chloride is not formed. 
 
 6. lodoform-Test for Alcohol. To 1 c.c. of alcohol in a test- 
 tube are added 10 c.c. of a moderately concentrated solution of 
 iodine in potassium-iodide solution, and potassium hydroxide 
 drop by drop till the brown colour of the iodine is discharged. 
 A yellow, crystalline precipitate of iodoform is obtained, dis- 
 tinguished by its characteristic odour. Under the microscope, 
 the crystals are seen to be six-sided, dichroic (reddish-green) 
 plates. 
 
 XIV. GLYCEROL. 
 
 (151-155.) 
 
 i. Preparation of Allyl Alcohol. 10 c.c. of glycerol and 
 12 g. of crystallized oxalic acid are heated in a retort connected 
 with a condenser. At first, formic acid distils (IX., i), and 
 
28 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xv. 
 
 soon oily streaks of allyl alcohol are seen on the sides of the 
 retort. The distillation is continued with another receiver, 
 this alcohol passing over. It is characterized by an irritating 
 odour. On heating it with chromic-acid solution, the powerful, 
 penetrating odour of acraldehyde is perceived. 
 
 2. Test for Glycerol. 1 c.c. of glycerol is heated in a dish 
 with 5 g. of sodium pyrosulphate, Na2S2Or; the odour of 
 acraldehyde is soon manifested. 
 
 3. Action of Alkalis on Copper Salts in Presence of Glycerol. 
 5 c.c. of dilute copper-sulphate solution are added to 1 c.c. of 
 glycerol. On addition of potassium hydroxide to this mixture, 
 copper hydroxide, Cu(OH)2, is not precipitated. Instead, a 
 soluble copper alkoxide of glycerol is formed, imparting a deep- 
 blue colour to. the solution. 
 
 XV. SATURATED DIBASIC ACIDS. 
 
 (161-168.) 
 OXALIC ACID (162). 
 
 i. Preparation of Oxalic Acid from Wood. A concentrated 
 solution of potassium (not sodium) hydroxide is added to 10 
 g. of sawdust, so as to form a thick paste, and the mixture 
 heated on a shallow iron dish, and constantly stirred. The 
 first product is potassium formate; on further heating, it loses 
 hydrogen, yielding potassium oxalate (2). The heating is 
 continued for a few minutes after rapid evolution of hydrogen 
 from the mass in large bubbles which burn on ignition has 
 begun, and then stopped, to prevent decomposition of the 
 oxalate formed. When cold, the reaction-mixture is lixiviated 
 with water, filtered through a folded filter, and acidified with 
 dilute acetic acid. On addition of calcium-chloride solution, 
 calcium oxalate is precipitated, insoluble in acetic acid, but 
 soluble in cold, and more readily in warm, hydrochloric acid. 
 
xv.] SATURATED DIBASIC ACIDS 29 
 
 2. Conversion of Formates into Oxalates. 2 g. of dried 
 sodium formate are heated to a high temperature in a test- 
 tube. Hydrogen is evolved, and can be ignited after all the 
 air has been expelled from the tube. The white residue is 
 proved to be sodium oxalate by dissolving it in water, and 
 adding a solution of calcium chloride; a precipitate of calcium 
 oxalate, insoluble in dilute acetic acid, is formed. 
 
 3. Calcium, Lead, and Copper Oxalates. These oxalates are 
 prepared by adding solutions of calcium chloride, lead acetate, 
 and copper sulphate respectively to a ten per cent, solution of 
 ammonium oxalate till precipitation is complete, 50 c.c. of the 
 ammonium-oxalate solution being used for each experiment. 
 The salts are collected on filters, washed thoroughly with 
 water, and spread on porous plates to dry. The last traces 
 of moisture are eliminated by heating them in porcelain dishes 
 on the water-bath. 
 
 4. Decomposition of Calcium Oxalate by Heat. 3 g. of cal- 
 cium oxalate are heated in a hard-glass test-tube fitted with a 
 delivery-tube. When the temperature has risen above 200, 
 water of crystallization condenses on the sides of the tube; 
 on further heating, carbon monoxide is evolved. The gas is 
 collected in a cylinder, and its identity established by the 
 method of IX., 3. The residue in the tube is calcium carbonate; 
 when cold, it is treated with hydrochloric acid, causing a vigor- 
 ous evolution of gas. This is proved to be carbon dioxide by 
 its action on lime-water. 
 
 5. Decomposition of Lead and Copper Oxalates by Heat. 
 The experiment described in 4 is carried out in separate tubes 
 with 3 g. of lead oxalate and a like weight of copper oxalate. 
 Both evolve carbon dioxide, as proved by the lime-water 
 test; lead and copper remain in the tubes. 
 
 6. Action of Concentrated Sulphuric Acid on Oxalic Acid. 
 A 100-c.c. distilling-flask is connected with a wash-bottle con- 
 taining a mixture of potassium-hydroxide solution and lime- 
 water and fitted with a delivery-tube. In the flask are placed 
 
30 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xv. 
 
 5 g. of oxalic acid and 10 c.c. of concentrated sulphuric acid. 
 The flask is closed with a cork, and heated gently. Gas is 
 evolved; partly carbon dioxide, which renders turbid the 
 lime-water in the wash-bottle; and partly carbon monoxide, 
 which is not absorbed. The latter is collected in cylinders, 
 and identified by the method of IX., 3. 
 
 7. Complex Oxalates. a) A solution of ammonium oxa- 
 late is added carefully to 2 c.c. of a five per cent, solution of 
 copper sulphate. Copper oxalate is precipitated, and, on 
 further addition of the ammonium salt, redissolves, forming 
 copper ammonium oxalate. 
 
 6) 2 g. of " salt of sorrel," KHC 2 O 4 ,H2C204,2H 2 0, are 
 dissolved in 10 c.c. of water. To this solution is added 
 freshly-precipitated ferric hydroxide, obtained by adding 
 ammonium hydroxide to a boiling, dilute solution of ferric 
 chloride, allowing the precipitate to subside, and washing it 
 by decantation. On warming, the ferric hydroxide dissolves, 
 yielding potassium ferric oxalate, KsFefX^O^s. The green 
 colour of this solution should be noted; it points to the absence 
 of Fe-ions, and to the presence of complex [Fe(C2O4)3] /// -anions. 
 
 c) A like solution of " salt of sorrel " is added to 5 c.c. of a 
 ten per cent, solution of ferrous sulphate until the precipitate 
 first formed redissolves. This solution reduces platinum 
 chloride. Its yellow colour is due to the complex [FefX^O^]"- 
 anion. 
 
 8. Action of Light on EDER'S Solution. A mixture of 2 
 volumes of a 4 per cent, solution of ammonium oxalate and 1 
 volume of a 5 per cent, solution of mercuric chloride (EDER'S 
 solution) is divided into two equal parts, and a few drops of 
 eosin solution are added to one of them. After exposure to 
 light for several hours, both of the liquid samples contain 
 a precipitate of mercurous chloride, the amount of this salt 
 deposited in the solution containing the sensitizer eosin being 
 much larger than in the other solution. 
 
 9. Dimethyl Oxalate. Oxalic acid is dried at 100, and 3 g. 
 
xv.] SATURATED DIBASIC ACIDS 31 
 
 of the dry acid are dissolved in 10 c.c. of boiling methyl alcohol. 
 On cooling, dimethyl oxalate crystallizes out. Some of the 
 ester is dried by pressure between sheets of filter-paper, and its 
 melting-point taken. M. P. 54. 
 
 10. Diethyl Oxalate. A mixture of 7 g. of anhydrous oxalic 
 acid and 10 c.c. of absolute alcohol is heated slowly in a 50-c.c. 
 fractionating-flask connected with a condenser till the temper- 
 ature rises to 110. The distillate is then returned to the flask, 
 and the heating continued till the thermometer reaches 180. 
 The fraction distilling between this temperature and 190 is 
 collected separately, and is principally diethyl oxalate. 
 
 11. Oxamide. The esters obtained in experiments 9 and 
 10 are dissolved separately in alcohol, and ammonium hydr- 
 oxide added to each solution. From both a precipitate of 
 oxamide is obtained, insoluble in water, alcohol, and ether. 
 
 SUCCINIC ACID (166). 
 
 12. Barium Succinate. Ammonium hydroxide is added to 
 10 c.c. of a cold, saturated solution of succinic acid till neutrali- 
 zation is complete. On addition of barium chloride, a white, 
 crystalline precipitate of barium succinate is formed, the 
 precipitation being facilitated by addition of alcohol. 
 
 13. Basic Ferric Succinate. 10 c.c. of a solution of succinic 
 acid are carefully neutralized, and ferric chloride added. A 
 brown, gelatinous precipitate of basic ferric succinate is formed. 
 
 14. Succinimide. A solution of 10 g. of succinic acid in 
 ammonium hydroxide is evaporated in a porcelain dish on a 
 sand-bath, and heated till the temperature of the fused mass is 
 about 200. The residue is transferred to a small fractionating- 
 flask, and distilled as rapidly as possible. The distillate is 
 succinimide, M. P. 125. It can be crystallized from alcohol. 
 
32 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xvi. 
 
 XVI. HYDROXY-ACIDS. 
 
 (179-197.) 
 LACTIC ACID (182). 
 
 1. Decomposition of Lactic Acid by Dilute Sulphuric Acid. 
 5 c.c. of lactic acid are heated with a mixture of 5 c.c. of con- 
 centrated sulphuric acid and 10 c.c. of water in a retort con- 
 nected with a condenser. The distillate contains acetaldehyde 
 and formic acid. They can be identified by the silver-mirror 
 test (X., 2), and the mercuric-oxide test (IX., 2), respectively. 
 
 2. Decomposition of Lactic Acid by Concentrated Sulphuric 
 Acid. A mixture of 5 c.c. of lactic acid and a like volume of 
 concentrated sulphuric acid is heated in a retort fitted with a 
 delivery-tube. The gas evolved by the decomposition of the 
 formic acid first produced can be proved to be carbon monoxide 
 by the method described in IX., 3. 
 
 3. Oxidation of Lactic Acid. Dilute sulphuric acid is 
 added to a solution of 0*5 g. of lactic acid, and the mixture 
 gently heated with a 2 per cent, solution of potassium perman- 
 ganate. The odour of acetaldehyde soon becomes perceptible. 
 
 TARTARIC ACID (188-196). 
 
 4. Potassium Tartrates. Potassium hydroxide is added 
 drop by drop to 5 c.c. of a twenty per cent, solution of tar- 
 taric acid. A precipitate of potassium hydrogen tartrate is 
 first formed, and, on further addition of potassium hydroxide, 
 redissolves, with production of the neutral tartrate. 
 
 5. Iron Ammonium Tartrate. A solution of 9 g. of ferrous 
 sulphate is added to 15 c.c. of a solution of 1 part of tartaric 
 acid in 2 parts of water; excess of ammonium hydroxide pro- 
 duces no precipitate with this mixture. When agitated in 
 presence of air, this liquid absorbs oxygen, becoming light- 
 green, then dark-green, and finally brown. The absorption 
 of oxygen can be demonstrated by carrying out the process in a * 
 flask closed with an air-tight cork; on immersion of the neck 
 in water and removal of the cork, the water rises in the flask. 
 
xvi.] HYDROXY-ACIDS 33 
 
 After replacement of the cork, the flask is withdrawn from 
 the water, and an ignited wood-splint introduced into the 
 residual gas; the flame is at once extinguished. 
 
 6. FEHLING'S Solution. A solution of copper sulphate is 
 added to one of tartaric acid, and then potassium hydroxide 
 in excess. The dark-blue liquid formed is known as FEHLING'S 
 solution. 
 
 7. Action of Heat on Tartaric Acid. When heated in a test- 
 tube, tartaric acid becomes brown, and acquires a caramel- 
 like odour. When heated on platinum-foil or nickel-foil, it 
 chars. 
 
 8. Microchemical Test for Tartaric Acid and Racemic Acid. 
 Calcium chloride is added to a solution of tartaric acid satu- 
 rated with ammonia. The calcium tartrate precipitated is 
 only slightly soluble in dilute acetic acid. 
 
 The experiment should be repeated with racemic acid, and the 
 crystals of the two calcium salts compared under the microscope. 
 
 9. Relative Solubility of Calcium Tartrate and Calcium Race- 
 mate. A solution of calcium sulphate is added to solutions 
 of tartaric acid and racemic acid respectively. On the follow- 
 ing day, calcium racemate is precipitated, but calcium tartrate 
 remains dissolved. 
 
 10. "Tartar Emetic. "A solution of potassium hydrogen 
 tartrate is prepared by dissolving 1 g. of tartaric acid in a 
 small quantity of water, neutralizing with potassium hydroxide, 
 and adding a concentrated solution of a second gramme of 
 tartaric acid. The precipitated potassium hydrogen tartrate 
 is redissolved by heating, after addition of a little water. To 
 this solution is added antimony oxide; it dissolves, forming 
 " tartar emetic." 
 
 CITRIC ACID (197). 
 
 11. Preparation from Lemons. A small quantity of water is 
 added to 10 c.c. of lemon-juice, the mixture filtered, and made 
 alkaline with ammonium hydroxide. On addition of calcium 
 
34 LABORATORY MANUAL OF ORGANIC CHEMISTRY [XVIL 
 
 chloride, no precipitate is formed; on boiling the mixture, 
 tricalcium citrate is precipitated, and is redissolved as the 
 liquid cools. 
 
 12. Action of Concentrated Sulphuric Acid on Citric Acid. 
 A solution of 5 g. of citric acid in cold, concentrated sulphuric 
 acid is heated in a distilling-flask, fitted with a delivery-tube. 
 The carbon monoxide evolved is identified by the method 
 described in IX., 3. 
 
 13. Formation of Acetone from Citric Acid. A solution of 
 0-5 g. of citric acid in a small quantity of water is heated to 
 80, and a few drops of a 2 per cent, solution of potassium 
 permanganate added. The colour is rapidly discharged. 
 After filtration, the liquid is saturated with ammonia, and a 
 solution of iodine added. lodoform is produced from the 
 acetone formed by the oxidation. 
 
 XVII. CHLORAL HYDRATE. 
 
 (201.) 
 
 1. Action of Water on Chloral. 3 g. of chloral hydrate are 
 covered with concentrated sulphuric acid, and the mixture 
 agitated. An oily layer of anhydrous chloral collects on the 
 surface of the acid. This is separated from the sulphuric 
 acid by the aid of a 50-c.c. tap-funnel, and brought into con- 
 tact with a small quantity of water; heat is evolved, and solid 
 chloral hydrate formed. 
 
 2. Action of Alkali Hydroxide on Chloral Hydrate. A small 
 quantity of potassium-hydroxide solution is added to 1 g. of 
 chloral hydrate dissolved in 10 c.c. of water. The odour of 
 chloroform becomes perceptible, and the liquid is rendered 
 turbid by the separation of minute drops of this substance. 
 The presence of formic acid in the solution is proved by warm- 
 ing it, after careful neutralization and addition of a small 
 quantity of mercuric chloride or silver nitrate (IX., 2). 
 
xvm.] ALDEHYDO-ALCOHOLS AND KETO-ALCOHOLS 35 
 
 3. Silver-mirror Test for Chloral Hydrate. A dilute solution 
 of chloral hydrate is warmed in a test-tube on a water-bath 
 with a small quantity of an ammoniacal solution of silver 
 nitrate, prepared in accordance with the method described in 
 X., 2. If the tube is clean, a silver mirror is deposited on its 
 sides. 
 
 4. Action of Sodium Hydrogen Sulphite on Chloral Hydrate. 
 A concentrated solution of sodium hydrogen sulphite is poured 
 over 3 g. of chloral hydrate, and the mixture vigorously 
 agitated. The hydrate at first dissolves, but the liquid soon 
 becomes a thick paste, owing to separation of the addition- 
 product. 
 
 XVIII. ALDEHYDO-ALCOHOLS AND KETO-ALCOHOLS OR 
 
 SUGARS. 
 
 (202-228.) 
 PROPERTIES OF THE MONOSES (203). 
 
 1. Silver-mirror Test. A ten per cent, solution of dextrose is 
 warmed in a clean test-tube in a water-bath with an ammoniacal 
 solution of silver nitrate prepared as in X., 2. A silver 
 mirror forms on the inner surface of the test-tube. 
 
 2. Resinification with Caustic Alkalis. A similar solution is 
 boiled with a small amount of a solution of potassium or 
 sodium hydroxide. The liquid turns yellow, then brown, 
 and finally resinifies. 
 
 3. Reduction of FEHLING'S Solution. On heating another 
 portion of the dextrose solution with FEHLING'S solution 
 (XVI., 6), reduction takes place, with formation of red 
 cuprous oxide. 
 
 4. Osazones. A solution of phenylhydrazine in sulphurous 
 acid is added to another portion of the dextrose solution in a 
 test-tube. On warming the mixture in a water-bath, phenyl- 
 
36 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xvm. 
 
 glucosazone precipitates in the form of microscopic, yellow 
 needles. 
 
 METHODS OF FORMATION OF THE MONOSES (206). 
 
 5. Inversion of Sucrose (Cane-sugar). A dilute solution of 
 sucrose is boiled for several minutes with a few drops of dilute 
 sulphuric acid. After this treatment, the solution answers to 
 the dextrose-tests described in 1-4. 
 
 6. Glycerose. A mixture of 10 g. of glycerol and 20 c.c. of 
 nitric acid of 1-18 specific gravity is heated in a beaker on the 
 water-bath until oxides of nitrogen are evolved, and cooled 
 quickly. After neutralization of the solution with potassium 
 or sodium hydroxide the presence of glycerose can be demon- 
 strated by reactions 1-4. 
 
 PENTOSES (207). 
 
 7. Furfuraldehyde-Test. To 10 g. of bran contained in a 
 half-litre flask is added a mixture of 5 g. of concentrated sul- 
 phuric acid and 70 c.c. of water. The flask is connected with a 
 condenser, and heated. The distillate contains furfur aldehyde 
 (393), characterized by its odour. The smell of fresh rye- 
 bread is due to the presence of furfuraldehyde. This aldehyde 
 can be identified in two ways. 
 
 a) On addition of a small quantity of aniline to the solu- 
 tion, followed by concentrated hydrochloric acid, the liquid 
 acquires an intense red colour. 
 
 b) A solution of phenylhydrazine in sulphurous acid is 
 added to the mixture containing furfuraldehyde, whereupon 
 furfuraldehyde-hydrazone is precipitated in the form of an 
 oil, which soon crystallizes. 
 
 HEXOSES (208). 
 
 8. Hydrochloric-acid Test. A solution of a hexose is boiled 
 with concentrated hydrochloric acid. The liquid becomes 
 
xvm.] ALDEHYDO-ALCOHOLS AND KETO-ALCOHOLS 37 
 
 brown and deposits " humic substances "; Isevulic acid remains 
 in solution (234). 
 
 Dextrose (208). 
 
 9. Calcium Alkoxide of Dextrose. Milk of lime is added 
 drop by drop to 10 c.c. of a solution of 1 part of dextrose in 2 
 parts of water, and the mixture agitated. The lime dissolves, 
 forming the calcium alkoxide or saccharate of dextrose. This 
 is decomposed by carbon dioxide, with precipitation of calcium 
 carbonate. 
 
 10. Glucosesulphuric Acid. 1 g. of dextrose is triturated 
 in a mortar with cold, concentrated sulphuric acid, added 
 drop by drop till solution is complete. Glucosesulphuric 
 acid is formed, and can be detected by diluting with water, 
 adding barium carbonate until the mixture, thoroughly blended 
 by the aid of the pestle, ceases to be acid, and filtering; the 
 filtrate contains the barium salt of glucosesulphuric acid. 
 Addition of dilute sulphuric acid decomposes the barium 
 glucosesulphate, precipitating barium sulphate. 
 
 11. Copper Alkoxide of Dextrose. A small quantity of a 
 solution of one part of dextrose in 2 parts of water is added to 
 2 c.c. of ten per cent, solution of copper sulphate. On addi- 
 tion of potassium hydroxide to the mixture, no precipitate 
 is formed, the formation of a copper alkoxide of dextrose 
 imparting a dark-blue colour to the solution. 
 
 12. Detection of Dextrose in Urine. A bismuth solution, 
 prepared by mixing solutions of bismuth nitrate, Rochelle 
 salt, and sodium hydroxide, is added to a 2 per cent, solution 
 of dextrose, and the mixture boiled. Black bismuthous 
 oxide, BiO, is precipitated. 
 
 13. Oxidation of Dextrose by Nitric Acid. A mixture of 
 1 g. of dextrose and 10 c.c. of nitric acid of 1-3 specific gravity 
 is evaporated to dryness on the water-bath. About 1 c.c. of 
 water is added to the residue, and 5 c.c, of a concentrated 
 
38 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xvm. 
 
 solution of potassium acetate. After a short time, potassium 
 hydrogen saccharate is precipitated. 
 
 L ae v u 1 o s e (209.) 
 
 14. Alcoholic Character. The alcoholic character of this 
 compound can be demonstrated by the methods employed for 
 dextrose (9-11). 
 
 15. Test for Laevulose. 1 c.c. of a ten per cent, solution 
 of Isevulose is heated with concentrated hydrochloric acid and 
 some crystals of resorcinol. The liquid turns dark-red. 
 
 d-Galactose (211). 
 
 1 6. Oxidation of d-Galactose to Mucic Acid. A solution of 
 1 g. of d-galactose is boiled for several minutes with nitric acid 
 of 1*3 specific gravity, evaporated to small bulk, diluted with 
 water, and cooled. Mucic acid separates as a crystalline 
 powder, soluble with difficulty in cold water. If d-galactose 
 cannot be obtained, lactose should be used instead (215). 
 
 A small quantity of the mucic acid is washed with water, 
 and a trace of it introduced into a drop of five per cent, 
 potassium-hydroxide solution on a microscope-slide. Under 
 the microscope, the characteristic, prismatic crystals of potas- 
 sium mucate make their appearance after a few moments. 
 
 HEXODIOSES (213-220) 
 
 Lactose (215). 
 
 17. Detection of Lactose in Milk. A few drops of dilute 
 acetic acid are added slowly to 25 c.c. of milk diluted with a 
 like volume of water, the liquid being thoroughly mixed by 
 stirring. The casein and fatty constituents of the milk are 
 thus precipitated. The mixture is filtered through a folded 
 filter. On warming part of the filtrate with FEHLING'S solu- 
 tion, the lactose causes reduction, with formation of red 
 
xvm.] ALDEHYDO-ALCOHOLS AND KETO-ALCOHOLS 39 
 
 cuprous oxide. The rest of the filtrate is evaporated with 
 dilute nitric acid to small bulk; d-galactose is formed by 
 inversion, and oxidized to mucic acid, which can be recognized 
 by the method of 16. 
 
 18. Lactosazone. On warming 5 c.c. of a ten per cent, 
 solution of lactose with a sulphurous-acid solution of phenyl- 
 hydrazine, an osazone phenyllactosazone is formed. 
 
 19. " Sand-sugar." The taste of lactose is not so sweet as 
 that of sucrose, and in the mouth it resembles sand, hence the 
 name sand-sugar. 
 
 Sucrose (216-220). 
 
 20. Properties Distinguishing Sucrose from the Monoses. 
 
 When heated with caustic alkalis, a ten per cent, solution of 
 sucrose does not resinify; it does not reduce FEHLING'S solu- 
 tion; and, when warmed with a solution of phenylhydrazine 
 in sulphurous acid, gives no osazone (1-4). 
 
 21. Action of Heat on Sucrose. On heating a small quantity 
 of sucrose in a test-tube, it turns brown, forming caramel, 
 and evolving the characteristic odour of this substance. 
 
 22. Tricalcium Saccharate. 10 c.c. of a twenty per cent, 
 solution of sucrose are agitated with sufficient milk of lime to 
 cause permanent turbidity, and filtered. When the filtrate 
 is boiled, the nearly insoluble tricalcium saccharate, with the 
 formula Ci2H220n,3CaO,3H 2 0, is precipitated; on cooling 
 it is dissolved. 
 
 23. Inversion. A solution of 2 g. of sucrose is inverted by 
 boiling for several minutes with dilute sulphuric acid. After 
 careful neutralization with sodium hydroxide, the solution 
 thus obtained has the properties characteristic of monoses, 
 described in 1-4, and answers to the Isevulose-test with resor- 
 cinol. 
 
40 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xvm. 
 
 POLYOSES (224-228.) 
 
 Starch (225 and 226). 
 
 24. Starch-paste. 5 g. of powdered starch are washed with 
 water on a filter-paper. The washed starch is transferred to a 
 beaker containing 200 c.c. of boiling water, a faintly opalescent 
 solution of starch-paste being obtained. 
 
 25. Properties Distinguishing Starch from the Monoses. 
 If the starch has been washed with sufficient care, this starch- 
 paste does not reduce FEHLING'S solution, and is not resinified 
 by alkalis. 
 
 26. Conversion of Starch into Dextrose. a) 50 c.c. of the 
 starch-paste solution are boiled with 10 c.c. of ten per cent, 
 sulphuric acid for fifteen minutes. After neutralization with 
 sodium hydroxide, the liquid has the properties characteristic 
 of monoses described in 1-4. 
 
 6) A mixture of 50 c.c. of the starch-paste with 10 c.c. 
 of fresh malt-extract, which contains diastase, is heated at 
 60 for about half an hour. The paste becomes liquefied, and 
 the liquid no longer answers to the iodine-test. 
 
 27. Iodine-test for Starch. A trace of an iodine solution is 
 added to one of starch-paste, a deep-blue coloration being 
 produced. On heating, this disappears, but on cooling returns, 
 provided the heating is not too prolonged. 
 
 28. Barium Alkoxide of Starch. A solution of barium 
 hydroxide is added to a boiling solution of starch-paste. The 
 barium alkoxide of starch is precipitated. 
 
 29. Conversion of Starch into Dextrin. a) A small quantity 
 of starch is heated carefully in a test-tube, the residue agitated 
 with cold water, and filtered. The filtrate contains dextrin, 
 proved by the yellow coloration developed by heating with 
 alkalis, its precipitation from solution on addition of alcohol, 
 and the red colour produced by addition of iodine solution. 
 
 6) 50 c.c. of concentrated hydrochloric acid is added to 
 5 g. of starch, the mixture becoming rapidly converted into 
 
xvm.] ALDEHYDO-ALCOHOLS AND KETO-ALCOHOLS 41 
 
 a transparent, opalescent paste. After the lapse of one or 
 two hours, the paste will have liquefied, and on the following 
 day will no longer answer to the iodine-test for starch, although 
 it will still show the reactions of dextrin. A few days later, 
 the liquid will only contain dextrose. 
 
 30. Potato-starch. A small quantity of potato-starch is 
 moistened with a few drops of water, a little of the mixture 
 transferred to a microscope-slide, and examined under the 
 microscope. The starch-granules are seen to have 'a charac- 
 teristic shell-like appearance (225, Fig. 69). 
 
 Cellulose (227 and 228). 
 
 31. Hydrolysis of Cellulose. A piece of filter-paper is dis- 
 solved in cold, concentrated sulphuric acid by the method 
 described in 10, the solution poured into water, and boiled for 
 half an hour. When neutralized with sodium hydroxide, it 
 answers to the tests for monoses (1-4). 
 
 32. Parchment-paper. A strip of filter-paper is immersed 
 in sulphuric acid containing half its volume of water, and at 
 once transferred to a large quantity of cold water, and thor- 
 oughly washed. This treatment converts the cellulose into 
 amyloid or parchment-paper, which gives a blue coloration 
 with iodine. Although wet, the parchment-paper is very tough, 
 and cannot be torn readily. 
 
 33. Solubility of Cellulose in SCHWEITZER'S Reagent. An 
 ammoniacal solution of copper oxide is prepared by adding 
 freshly-precipitated, washed copper hydroxide to 10 c.c. of 
 concentrated ammonium hydroxide till no more dissolves. 
 When placed in this solution, filter-paper (cellulose) dissolves. 
 On addition of dilute hydrochloric acid, the colour is discharged, 
 and an amorphous, flocculent precipitate of cellulose deposited. 
 
 34. Nitrocelluloses. A small piece of cotton-wool is 
 immersed for several seconds in a cold mixture of one part 
 of concentrated nitric acid and two parts of concentrated 
 
42 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xix. 
 
 sulphuric acid, nitre-celluloses being formed. It is then 
 washed carefully with much cold water, and dried at the ordi- 
 nary temperature. A part held with tongs in a Bunsen flame 
 burns energetically. Another portion is agitated with a mix- 
 ture of alcohol and ether, and the liquid named collodion 
 poured on a glass plate; on evaporation of the solvent, a 
 transparent skin is left. 
 
 The remainder of the nitrocelluloses is moistened with a 
 small quantity of ethyl acetate. A gelatinous mass is formed, 
 which, when dry, burns slowly ("smokeless powder "). 
 
 35. Detection of Lignin in Paper. A sheet of paper is 
 coated with a solution of aniline in hydrochloric acid. If 
 made from wood, the paper acquires an intense yellow colour. 
 
 XIX. PROTEINS. 
 (246-254.) 
 
 1. Detection of Nitrogen and Sulphur in the Proteins. 
 A few cubic centimetres of a solution of egg-albumin prepared 
 by dissolving white-of-egg in five times its volume of water 
 is heated with potassium hydroxide. Ammonia is evolved, 
 and can be detected by the aid of a moist strip of red litmus- 
 paper. 
 
 The liquid is diluted with water, and lead acetate added. 
 The potassium sulphide formed in the last experiment reacts 
 with the lead salt, precipitating black lead sulphide. 
 
 2. " Salting-out " Proteins with Ammonium Sulphate. Solid 
 ammonium sulphate is added to 20 c.c. of the egg-albumin 
 solution. The albumin is precipitated. 
 
 3. Coagulation of Proteins by Alcohol. Strong alcohol added 
 to a solution of egg-albumin gives a precipitate of coagulated 
 egg-albumin. A similar precipitate is formed when an aqueous 
 solution of egg-albumin is boiled. Coagulated egg-albumin 
 
xx.] HYDROCYANIC ACID 43 
 
 is soluble in dilute caustic alkali, concentrated hydrochloric 
 acid, and concentrated sulphuric acid. 
 
 4. Coagulation of Proteins by Nitric Acid. Dilute nitric acid 
 is added to an egg-albumin solution prepared by the method 
 of i. The egg-albumin is precipitated. 
 
 5. Biuret-reaction. A few drops of copper-sulphate solu- 
 tion are added to 5 c.c. of a solution of egg-albumin. Careful 
 addition of dilute potassium hydroxide to the mixture pre- 
 cipitates copper albuminate. Excess of potassium hydroxide 
 redissolves the precipitate, producing a violet-red coloration. 
 
 6. MiLLON'S Reagent. On boiling an egg-albumin solution 
 with MILLON'S reagent a solution of mercuric nitrate con- 
 taining nitrous acid a red, coagulated mass is obtained. 
 
 7. Xanthoprotem-reaction. When an egg-albumin solution 
 is warmed with dilute nitric acid, it coagulates, with produc- 
 tion of a yellow coloration. 
 
 8. ADAMKIEWICZ'S Reaction. With concentrated sulphuric 
 acid a solution of egg-albumin in glacial acetic acid yields a 
 violet coloration, due to the presence in the mixture of a small 
 proportion of glyoxylic acid. 
 
 9. Decomposition-products of Keratin. A feather is heated 
 with concentrated potassium hydroxide. It dissolves, and the 
 solution thus obtained gives the reactions for nitrogen and 
 sulphur, described in i. CALIFORNIA COLl 
 
 of PHARMACY 
 
 XX. HYDROCYANIC ACID, AND ITS SIMPLE AND 
 COMPLEX SALTS. 
 
 (256 and 257.) 
 
 i. Hydrocyanic Acid. 10 c.c. of a cold, saturated solution 
 of potassium ferrocyanide are poured into a distilling-flask 
 connected with a condenser, and 20 c.c. of twenty per cent, 
 sulphuric acid added. The open end of the condenser is 
 dipped into a test-tube containing water and a few drops of 
 
44 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xx. 
 
 concentrated potassium or sodium hydroxide. On heating, 
 hydrocyanic acid distils, and is converted into potassium 
 cyanide. 
 
 2. Prussian-blue Test. A mixture of a ferrous salt and a 
 ferric salt is added to part of the solution obtained in the 
 last experiment. On acidifying with hydrochloric acid, a 
 precipitate of Prussian blue is formed (I., 3 a). 
 
 3. Silver Cyanide. A drop of a dilute solution of silver 
 nitrate is added to 10 c.c. of a solution of 1 g. of potassium 
 cyanide in 100 c.c. of water. On agitating the mixture, the 
 precipitate first formed redissolves, yielding a double cyanide 
 of potassium and silver, KAg(CN) 2 . On further addition of 
 silver nitrate, a permanent precipitate of silver cyanide, AgCN, 
 is obtained. 
 
 4. Hydrolysis of Potassium Cyanide. 25 c.c. of the solution 
 of potassium cyanide prepared for experiment 3 are boiled in a 
 flask. The evolved ammonia turns a strip of red litmus-paper 
 blue. 
 
 5. Conversion of Ammonium Formate into Hydrocyanic Acid. 
 3 g. of ammonium formate are submitted to dry distillation 
 in a small distilling-flask connected with a condenser dipping 
 into a test-tube with very dilute sodium hydroxide. The 
 presence of hydrocyanic acid in the distillate can be demon- 
 strated by the Prussian-blue test (2). 
 
 6. Double Ferrocyanide of Potassium and Calcium. A small 
 quantity of a calcium-chloride solution is added to a cold, 
 saturated solution of potassium ferrocyanide. The double 
 ferrocyanide, K2CaFe(CN)e, is precipitated. 
 
 7. Ferrocyanic Acid. Concentrated hydrochloric acid is 
 added to 5 c.c. of a strong solution of potassium ferrocyanide. 
 White ferrocyanic acid, H 4 Fe(CN)6, is precipitated. When 
 collected on a filter-paper, it soon turns blue, Prussian blue 
 being formed by decomposition and oxidation. 
 
 8. Action of Concentrated Sulphuric Acid on Potassium 
 Ferrocyanide. 5 g. of potassium ferrocyanide are warmed 
 
xxi.] POTASSIUM CYANATE AND THIOCYANATE 45 
 
 with concentrated sulphuric acid in a fractionating-flask. 
 The evolved carbon monoxide can be identified by the method 
 described in IX., 3. 
 
 9. Action of Heat on Potassium Ferrocyanide. 2 g. of potas- 
 sium ferrocyanide are heated to redness in a crucible; when 
 cold, the residue is lixiviated with water, and the mixture 
 filtered quickly. The solution contains potassium cyanide, as 
 can be proved by the Prussian-blue and silver-nitrate tests 
 (2 and 3). 
 
 10. Potassium Ferricyanide.- Bromine-water is added to 
 a solution of potassium ferrocyanide, which converts it into 
 potassium ferricyanide. This change is detected by addition 
 of ferric chloride, which produces a brown coloration, instead 
 of a precipitate of Prussian blue. 
 
 11. Reduction of Potassium Ferricyanide. Litharge, PbO, 
 is added to a solution of potassium ferricyanide containing 
 potassium hydroxide. The solid becomes brown, the lead 
 monoxide being oxidized to lead dioxide, PbC>2. After filter- 
 ing, and adding ferric chloride to the filtrate, a precipitate of 
 Prussian blue is formed, proving the presence of potassium 
 ferrocyanide. 
 
 12. Oxidation of Potassium Ferrocyanide by Potassium Per- 
 manganate. Sulphuric acid is added to a dilute solution of 
 potassium ferrocyanide. This mixture decolorizes potassium 
 permanganate, forming potassium ferricyanide, which gives 
 a brown coloration with ferric chloride. 
 
 XXI. POTASSIUM CYANATE AND POTASSIUM 
 THIOCYANATE. 
 
 (258-260.) 
 
 i. Potassium Cyanate. Litharge, PbO, is added to 3 g. of 
 fused potassium cyanide in a crucible so long as reduction to 
 metallic lead is rapid. The potassium cyanate, KCNO, formed 
 
46 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxn. 
 
 is extracted with cold water. On addition of sulphuric acid, 
 carbon dioxide is evolved, since the liberated cyanic acid 
 reacts at once with the water to form carbon dioxide and 
 ammonia. The liquid in the flask is made alkaline with 
 sodium hydroxide, and heated. The evolved ammonia turns 
 blue a strip of moist, red litmus-paper held in the mouth of 
 the flask. 
 
 2. Potassium Thiocyanate. 10 c.c. of potassium-cyanide 
 solution are boiled for some minutes with " flowers of sulphur " 
 and filtered. Addition of ferric chloride to the filtrate gives 
 a blood-red coloration, proving the formation of potassium 
 thiocyanate. 
 
 3. Silver Thiocyanate. With silver nitrate a solution of 
 potassium thiocyanate produces a white, cheese-like precipi- 
 tate of silver thiocyanate, AgCNS, insoluble in dilute nitric 
 acid. 
 
 XXII. DERIVATIVES OF CARBONIC ACID. 
 
 (263-270.) 
 CARBON BISULPHIDE (264). 
 
 1. Inflammability. A few drops of carbon disulphide are 
 poured into a porcelain basin, and ignited. The liquid burns 
 with a blue flame, forming carbon dioxide and sulphur dioxide, 
 the presence of the latter being made evident by its character- 
 istic, suffocating odour. 
 
 2. Volatility. On blowing upon a few drops of carbon 
 disulphide in the palm of the hand, a sensation of cold is expe- 
 rienced. 
 
 3. Solvent Power. Some linseed is crushed in a mortar, 
 transferred to a test-tube, and covered with a small quantity 
 of carbon disulphide. After about a minute, the liquid is 
 poured on a clock-glass or watch-glass, and allowed to evapo- 
 rate spontaneously. The residue is linseed oil. 
 
xxii.] DERIVATIVES OF CARBONIC ACID 47 
 
 4. Barium Trithio carbonate. 5 g. of barium sulphide are 
 L oiled with water for a few seconds, and the mixture filtered. 
 About 1 c.c. of carbon disulphide is added to the warm fil- 
 trate, the mixture vigorously shaken, and allowed to cool. A 
 yellow precipitate of barium trithiocarbonate is deposited. 
 
 5. Potassium and Copper Salts of Xanthic Acid. 10 c.c. of a 
 twenty per cent, solution of potassium hydroxide in absolute 
 alcohol is agitated with successive quantities of carbon disul- 
 phide, till potassium xanthate separates out. The precipita- 
 tion of the salt is facilitated by addition of a small amount 
 of ether. It is collected on a filter, dried between layers of 
 filter-paper, and dissolved in water. On adding a solution 
 of copper sulphate, a brownish-black precipitate of cupric 
 xanthate is formed. This substance changes so quickly to 
 yellow cuprous xanthate as to render its formation hardly 
 perceptible. In a dilute solution of the xanthate the reaction 
 is much slower. 
 
 UREA (266 and 267). 
 
 6. WOHLER'S Synthesis. Potassium cyanate, prepared by 
 the method of XXI., i, is dissolved in water. Ammonium sul- 
 phate is added, producing potassium sulphate and ammonium 
 cyanate. The solution is evaporated almost to dryness on 
 the water-bath, and the urea formed by the intramolecular 
 rearrangement of the ammonium cyanate extracted with 
 alcohol. The solvent is distilled, leaving a residue of urea. 
 
 7. Urea Oxalate. The urea obtained in the last experiment 
 is dissolved in a very small quantity of water, and a concen- 
 trated solution of oxalic acid added. A crystalline precipitate 
 of urea oxalate is deposited. 
 
 8. Urea Nitrate from Urine. About 10 c.c. of urine are 
 evaporated to small bulk on a water-bath, and the residue 
 allowed to cool. On addition of a few cubic centimetres of 
 colourless nitric acid of 1*4 specific gravity, a precipitate of 
 urea nitrate is formed. The mother-liquor is poured off, and 
 
48 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxn. 
 
 the nitrate purified by crystallization from a small quantity 
 of hot water. 
 
 9. KNOP'S Method for the Estimation of Urea in Urine. A so- 
 lution of bromine in cold potassium hydroxide is added to 10 c.c. 
 of urine contained in a distilling-flask fitted with a delivery- 
 tube. The urea at once begins to decompose, evolving nitrogen, 
 which is collected over water, and tested with a lighted taper. 
 
 10. BUNSEN'S Method for the Estimation of Urea in Urine. 
 10 c.c. of urine are heated with baryta-water in a flask. A 
 strip of red litmus-paper held in the mouth of the flask is turned 
 blue by the ammonia liberated. At the same time, the precip- 
 itated barium carbonate renders the liquid turbid. 
 
 11. LiEBlG'S Method for the Estimation of Urea in Urine. 
 A solution of mercuric nitrate is added to 10 c.c. of a two per 
 cent, solution of urea. A white precipitate of the composition 
 2CON 2 H4,Hg(N0 3 )2,3HgO is formed. When excess of the 
 mercuric nitrate has been added, a drop of the solution brought 
 into contact with one of sodium carbonate gives a yellow 
 precipitate of basic nitrate of mercury. 
 
 12. Action of Heat on Urea. 1 g. of urea is carefully heated 
 in a test-tube; it melts, and evolves ammonia, which can be 
 identified by means of a strip of red litmus-paper. The 
 fused mass soon re-solidifies, and the heating is stopped. The 
 residue is lixiviated with a small quantity of cold water, biuret 
 going into solution. This substance can be identified by the 
 biuret-reaction. Potassium hydroxide and one or two drops of a 
 ten per cent, solution of copper sulphate are added to the liquid; 
 the violet-red coloration produced is due to the formation of a 
 copper compound of biuret. 
 
 13. Cyanuric Acid. This substance is the principal con- 
 stituent of the residue in the test-tube after solution of the 
 biuret in the last experiment. It is dissolved in warm water; 
 after cooling, addition of copper sulphate and ammonium 
 hydroxide gives a crystalline, violet precipitate of copper 
 ammonium cyanurate. 
 
xxiii.] URIC ACID GROUP 49 
 
 CARBAMIC ACID (268). 
 
 14. Calcium Carbamate. Ammonium hydroxide is added 
 to 10 c.c. of a ten per cent, solution of calcium chloride. On 
 passing carbon dioxide through the mixture, no precipitate is 
 obtained, the calcium carbamate formed being soluble in water. 
 When the solution is warmed, the carbamate decomposes, 
 precipitating calcium carbonate. 
 
 15. Ammonium Dithiocarbamate. A drop of carbon disul- 
 phide is added to a concentrated alcoholic solution of ammonia 
 contained in a porcelain dish, and the mixture is evaporated to 
 dryness on a water-bath. The initial product formed is ammo- 
 nium dithiocarbamate. It is decomposed by the excess of 
 ammonia present into ammonium thiocyanate and ammonium 
 sulphide. The sulphide volatilizes, and the presence of the thio- 
 cyanate in the residue is detected by dissolving it in water, and 
 adding a few drops of dilute hydrochloric acid and ferric chloride. 
 The formation of ferric thiocyanate produces a blood-red color- 
 ation. 
 
 XXIII. URIC ACID GROUP. 
 
 (271-273.) 
 
 1. Ammonium Urate. A mixture of 50 c.c. of urine and 
 2-5 c.c. of a concentrated solution of sodium carbonate is 
 placed in a flask, and 5 c.c. of a saturated ammonium-chloride 
 solution added. After a short interval, ammonium urate is 
 precipitated. 
 
 2. Di-potassium Urate. A small quantity of uric acid is 
 agitated with water; it does not dissolve. On addition of 
 dilute potassium hydroxide, the readily soluble di-potassium 
 salt is formed, and can be reconverted into uric acid by dilute 
 acids. 
 
 3. Murexide-test for Uric Acid. A few cubic centimetres of 
 nitric acid of 1-4 specific gravity are added to 0-5 g. of uric 
 acid in a porcelain dish, and the mixture evaporated nearly 
 to dryness on a water-bath. In addition to other products, 
 alloxantine is formed. When treated with ammonium hydr- 
 
50 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxiv. 
 
 oxide, it forms a purple-red dye mu-rexide, the ammonium 
 salt of purpuric acid. 
 
 4. Reduction of Silver Nitrate by Uric Acid. A small quan- 
 tity of uric acid is dissolved in a few drops of sodium-carbonate 
 solution. When the liquid is brought into contact with filter- 
 paper moistened with a solution of silver nitrate, a black 
 stain of metallic silver is formed, in consequence of the reduc- 
 ing action of the uric acid. 
 
 5. Murexide-test for Caffeine. A few cubic centimetres of 
 nitric acid of 1 4 specific gravity are added to 0*5 g. of caf- 
 feine in a porcelain dish, and evaporated almost to dryness on 
 a water-bath. A yellow stain of amalic acid, or tetramethyl- 
 alloxantine, is left. On moistening this with ammonium 
 hydroxide, it becomes purple. 
 
 XXIV. BENZENE AND ITS HOMOLOGUES. 
 (281-288.) 
 
 1. Stability of Benzene towards the Halogens. On agitating 
 a few cubic centimetres of benzene with bromine-water, the 
 bromine is dissolved by the benzene, but its colour is not 
 discharged. 
 
 2. Absence of Double Bonds in Benzene. Benzene is agi- 
 tated with a solution of potassium permanganate and sodium 
 carbonate VON BAEYER'S reagent (113 and 281). The 
 violet-red colour remains unaltered. 
 
 3. Nitrobenzene. 2 c.c. of benzene are added drop by 
 drop to a mixture of 4 c.c. of concentrated sulphuric acid and 2 
 c.c. of nitric acid of 1-5 specific gravity, the flask being cooled 
 with running water to prevent rise of temperature. The 
 benzene dissolves, and, on pouring the acid mixture into 
 water, nitrobenzene separates and sinks to the bottom. It 
 has a characteristic odour, resembling that of oil of bitter 
 almonds. 
 
 4. Benzenemonosulphonic Acid. 5 c.c. of benzene are 
 brought gradually into contact with 10 c.c. of fuming sulphuric 
 
xxv] MONOHALOGEN COMPOUNDS 51 
 
 acid. At first heat is developed, and tlie hydrocarbon dis- 
 solves quickly; to complete the reaction, the mixture must be 
 warmed gently. It is then poured into twice its volume of 
 water, common salt added, and the liquid heated until hydro- 
 chloric-acid gas is evolved. On cooling, sodium benzenesul- 
 phonate separates in crystalline plates. 
 
 5. FRIEDEL and CRAFTS'S Reaction. 1 g. of aluminium 
 chloride is added to 5 c.c. of benzene, and a small quantity 
 of chloroform dropped into the mixture. There is a vigorous 
 evolution of hydrochloric-acid gas, and triphenylmethane is 
 formed. 
 
 6. Formation of Benzene from Calcium Benzoate. 10 g. of 
 calcium benzoate are mixed with a like weight of soda-lime, 
 and heated in a retort connected with a condenser. Benzene 
 distils, and can be identified by its odour, by the fact that it 
 floats on water, and by converting it into nitrobenzene with a 
 mixture of concentrated nitric and sulphuric acids in accord- 
 ance with the method described in 3. 
 
 7. Oxidation of Side-chains. 1 c.c. of toluene is heated 
 with a solution of potassium permanganate and sodium car- 
 bonate. The purple colour is discharged, and manganese 
 dioxide precipitated, in consequence of the oxidation of the 
 side-chain and the formation of benzole acid. 
 
 XXV. MONOHALOGEN COMPOUNDS. 
 
 (289.) 
 
 i. Stability of Monochlorobenzene towards Alcoholic Potash 
 or Soda. 5 c.c. of monochlorobenzene are heated with 10 c.c. 
 of ten per cent, alcoholic potash or soda for a few minutes, and 
 the liquid diluted with water. The monochlorobenzene is 
 precipitated unchanged as an oily liquid. To prove this, it is 
 separated by means of a tap -funnel, dried by contact with 
 granulated calcium chloride for a few minutes, and its boiling- 
 point determined by the method of III., 5. Monochloro- 
 benzene boils at 132. 
 
52 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxvi. 
 
 After separation of the monochlorobenzene, the aqueous 
 liquid is acidified with nitric acid, and silver nitrate added. 
 It does not become turbid, proving that the caustic alkali 
 has not reacted with the Cl-atom of the monochlorobenzene. 
 
 XXVI. MONOHYDRIC PHENOLS. 
 (292-294.) 
 
 1. Preparation of Phenol by Fusion of Sodium Benzenesul- 
 phonate with Sodium Hydroxide. 10 g. of sodium benzene- 
 sulphonate, 3 g. of sodium hydroxide, and a small quantity 
 of water are heated in an iron dish to the temperature of fusion, 
 the mixture being continually stirred. When cold, it i:> dis- 
 solved in water, the solution poured into a fractional ing- 
 flask, and dilute sulphuric acid added slowly. Much sulphur 
 dioxide is evolved, and can be recognized by its characteristic 
 odour. The flask is connected with a condenser, and heated. 
 Phenol distils along with water, and is identified by the methods 
 of 4 and 5. 
 
 2. Preparation of Pherol from Calcium Salicylate. 10 g. of 
 calcium salicylate are heated in a retort connected with a con- 
 denser. Phenol distils, and can be recognized by its odour, 
 and by the reactions described in 4 and 5. 
 
 3. Sodium Phenoxide. 1 g. of phenol is agitated with enough 
 water to form an emulsion; on addition of sodium-hydroxide 
 solution, this dissolves, forming sodium phenoxide. When 
 carbon dioxide is passed through the liquid for a considerable 
 time, phenol is liberated, and the mixture rendered turbid. 
 
 4. Tribromophenol. Bromine-water is added to a two 
 per cent, aqueous solution of phenol. Tribromophenol is 
 precipitated. 
 
 5. Ferric-chloride Test for Phenol. On addition of a drop of 
 ferric-chloride solution to a one per cent, solution of phenol, 
 an intense violet coloration is obtained. 
 
xxvii.] MONOAMINO-COMPOUNDS 53 
 
 6. Depression of the Freezing-point of Phenol. 5 c.c of 
 
 phenol are melted in a test-tube by very careful heating over a 
 tiny flame. After introduction of a thermometer, the liquid is 
 allowed to cool. When crystals begin to form, the mercury 
 ceases falling, and rises, the highest temperature indicated 
 being the freezing-point. For anhydrous phenol, it is 
 39-6. 
 
 The phenol is again melted, and 1 drop about 0*05 g. 
 of water added. The freezing-point is determined as before, 
 and found to be about 4 lower. 
 
 7. Action of Nitric Acid on Phenol. A cubic centimetre of 
 phenol is added drop by drop to 10 c.c. of nitric acid of specific 
 gravity 1-3, the liquid being continually agitated, and finally 
 heated to boiling. On cooling, picric acid is precipitated. 
 When recrystallized from water, it is obtained as yellow, 
 needle-like crystals. 
 
 8. Cresol. With bromine-water and ferric chloride respec- 
 tively, an aqueous solution of cresol gives reactions similar to 
 those obtained with phenol (4 and 5). 
 
 XXVII. MONOAMINO-COMPOUNDS AND THEIR 
 DERIVATIVES. 
 
 (296-301). 
 
 i. Aniline. 35 c.c. of hydrochloric acid of 1-19 specific 
 gravity are poured into a flask containing 6 g. of nitrobenzene, 
 and 18 g. of tin-powder added in successive small portions. 
 To prevent its contents becoming overheated, the flask is 
 shaken, and cooled with water. The nitrobenzene is reduced 
 to aniline, this combining with the excess of hydrochloric acid 
 to aniline hydrochloride. When all the nitrobenzene has 
 dissolved, and its odour is no longer perceptible, the aniline 
 is set free by potassium or sodium hydroxide, and the mixture 
 
54 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxvn. 
 
 distilled. The aniline volatilizes with the steam, rendering 
 the distillate turbid. 
 
 2. Neutral Reaction of Aniline. A small quantity of aniline 
 is agitated with water. The solution thus prepared neither 
 imparts a colour to phenolphthalein, nor turns red litmus 
 blue. 
 
 3. Aniline Salts. On addition of an acid, the turbid liquid 
 obtained in i becomes clear, a soluble aniline salt being formed. 
 Potassium or sodium hydroxide reprecipitates the aniline as 
 an oil. 
 
 4. Tribromoaniline. With an aqueous solution of aniline 
 or of one of its salts, bromine-water gives a precipitate of tri- 
 bromoaniline. 
 
 5. Bleaching-powder Test for Aniline. A few drops of ani- 
 line are agitated with water, and the solution separated from 
 undissolved amine by passing it through a moist filter. A 
 small quantity of a clear solution of bleaching-powder gives 
 a deep-violet coloration with the filtrate. 
 
 6. Potassium-dichromate Test for Aniline. 2 or 3 drops of 
 aniline are dissolved in dilute sulphuric acid. On addition 
 of potassium-dichromate solution, a precipitate green, blue, 
 or black according to the concentration is obtained. The 
 black precipitate is called aniline-black. 
 
 7. Acetoanilide. A mixture of 9 c.c. of aniline and a like 
 volume of glacial acetic acid is boiled in a flask with a reflux- 
 condenser for several hours. On cooling, crystals of acetoanilide 
 (" antifebrine ") are deposited. When recrystallized from a 
 small quantity of alcohol, they melt at 112. 
 
 8. Carbylamine-Reaction. Aniline can be proved to be a 
 primary amine by the carbylamine-reaction (VII., 2). 
 
 9. Diphenylamine. (M g. of diphenylamine is dissolved 
 in a small quantity of alcohol, and water is carefully added 
 until the liquid has become very turbid. The amine is now 
 suspended in the liquid in a fine state of division, and can 
 be dissolved by addition of concentrated hydrochloric acid 
 
xxvii.] MONOAMINO-COMPOUNDS 55 
 
 drop by drop. On dilution of this solution with water, the 
 diphenylamine is reprecipitated, the hydrochloride undergoing 
 hydrolytic dissociation. 
 
 10. Nitrosodimethylaniline. 1-4 g. of sodium nitrite dis- 
 solved in water is added gradually to a well-cooled solution of 
 2-4 g. of dimethylaniline in 12-5 g. of twenty per cent, hydro- 
 chloric acid. Yellow nitrosodimethylaniline hydrochloride is 
 precipitated. It is collected on a filter, washed with dilute 
 hydrochloric acid, and purified by crystallization from hot 
 water. The salt is triturated with water, sodium hydroxide 
 is added, and the green nitrosodimethylaniline liberated is 
 dissolved in ether. On distilling the ether, the base is obtained 
 in splendid, yellowish-green leaves. The crystals are boiled 
 with sodium hydroxide, whereby dimethylamine is evolved, 
 and the liquid becomes dark-red owing to the formation of 
 sodium nitrosophenoxide. The dimethylamine can be identified 
 by its characteristic odour, and its alkaline reaction to litmus. 
 
 11. LlEBERMANN'S Test for Aromatic Nitroso-compounds. 
 A few drops of concentrated sulphuric acid are added to a 
 solution of 0*5 g. of nitrosodimethylaniline in phenol. After 
 slight heating, the mixture is poured into water. Addition 
 of sodium hydroxide produces a fine dark-blue colour. 
 
 12. Azobenzene, Hydrazobenzene, and Benzidine Sulphate. 
 A mixture of 2 c.c. of nitrobenzene and 20 c.c. of twenty 
 per cent, alcoholic potash is gently warmed, and small quan- 
 tities of zinc-dust added. In consequence of the formation 
 of azobenzene, the liquid develops a red colour. On addition of 
 more zinc-dust, the colour is discharged, and hydrazobenzene 
 produced. When the liquid is poured into a quantity of 
 dilute sulphuric acid sufficient to make it strongly acid, nearly 
 insoluble benzidine sulphate is soon precipitated. 
 
 13. Diphenylurea. 1 g. of urea and 3 g. of aniline are 
 heated in a test-tube to ebullition, and the evolution of ammonia 
 proved by means of litmus-paper. When the reaction-mixture 
 is cooled by pouring it into a dish, crystallization of diphenyl- 
 
56 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxvm. 
 
 urea causes solidification. After elimination of excess of 
 aniline by means of dilute hydrochloric acid, the residue is 
 washed with water, and recrystallized from alcohol. The 
 melting-point of the product should be 235. 
 
 XXVIII. DIAZO-COMPOUNDS AND HYDRAZINES. 
 (305-310.) 
 
 1. Benzenediazonium Chloride. 9-3 g. of aniline are dis- 
 solved in about 100 c.c. of hydrochloric acid containing 9-2 
 g. of HC1. To this solution, maintained between 5 and 10 
 by the introduction of ice, is added very slowly a concentrated 
 aqueous solution of 7-2 g. of commercial sodium nitrite, the 
 liquid being stirred constantly. The solution of benzenedi- 
 azonium chloride thus obtained is kept in a vessel surrounded 
 by ice, and used for experiments 2, 3 and 4. 
 
 2. Replacement of N2-Group in Benzenediazonium Chloride 
 by Hydroxyl. A small quantity of the solution of benzene- 
 diazonium chloride is warmed in a fractionating -flask con- 
 nected with a condenser. When the evolution of nitrogen 
 has ceased the solution is distilled, water and phenol passing 
 over. The latter can be identified by its odour, and by reac- 
 tions XXVI., 4 and 5. 
 
 3. GATTERMANN'S Reaction. A paste of finely -divided cop- 
 per, obtained by sieving zinc -dust into a dilute solution of copper 
 sulphate, is added to a portion of the solution of benzenediazon- 
 ium chloride. Nitrogen is at once evolved with effervesence. 
 On distilling the liquid with steam, chlorobenzene collects in 
 the receiver. 
 
 4. Diazoaminobenzene. Aniline is mixed with ten times its 
 volume of water, and enough hydrochloric acid to give a clear 
 
 . solution. Addition of part of the solution of benzenediazonium 
 chloride prepared in i and solid sodium acetate produces a 
 yellow or brown precipitate of diazoaminobenzene. 
 
 5. Aminoazobenzene. A small quantity of diazoamino- 
 benzene is warmed gently with about twice its volume of 
 
xxix.] BENZOIC ACID AND ITS DERIVATIVES 57 
 
 aniline and some solid aniline hydrochloride. Aminoazobenzene 
 is formed. On addition of concentrated hydrochloric acid and 
 solid salt, steel-blue needles of aminoazobenzene hydrochloride 
 are obtained. 
 
 6. Oxidation of Phenylhydrazine by FEHLING'S Solution. 
 A drop of phenylhydrazine on a watch-glass is mixed with 
 a small quantity of concentrated hydrochloric acid, phenyl- 
 hydrazine hydrochloride, nearly insoluble in dilute hydro- 
 chloric acid, being formed. After pouring off the excess of 
 hydrochloric acid, a small quantity of the salt is dissolved in 
 water in a test-tube, and FEHLING'S solution (XVI., 6) added. 
 Reduction takes place at ordinary temperature, with formation 
 of cuprous oxide, Cu20. 
 
 XXIX. BENZOIC ACID AND ITS DERIVATIVES. 
 (311-313.) 
 
 1. Benzonitrile and Benzoi'c Acid. 10 g. of sodium ben- 
 zenesulphonate are mixed with a like weight of dried potassium 
 ferrocyanide, and the mixture submitted to dry distillation in a 
 retort connected with a condenser. Benzonitrile and a trace 
 of phenylcarbylamine distil. The ^sonitrile is decomposed by 
 warming with two drops of concentrated hydrochloric acid. 
 About 20 c.c. of ten per cent, potassium hydroxide are added, 
 and the mixture is boiled in a flask with a reflux-condenser. 
 Ammonia is evolved, as can be proved by red litmus-paper, 
 while the oily layer of benzonitrile disappears. The flask is 
 cooled, and concentrated hydrochloric acid added slowly; 
 a white, flocculent precipitate of benzoic acid is deposited. 
 
 2. Benzoic Acid from Gum-benzoin. a) 5 g. of finely- 
 powdered gum-benzoin are mixed with sand, and heated very 
 gently in a porcelain dish on a sand-bath, care being taken to 
 avoid fusion. The dish is covered with a hollow paper-cone, 
 into which the benzoic acid sublimes. 
 
 6) 5 g. of gum-benzoin are boiled with milk of lime, the 
 alkaline solution filtered, and hydrochloric acid added. Benzoic 
 acid is precipitated. 
 
58 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxix. 
 
 3. Volatility of Benzole Acid with Steam. 1 g. of benzole 
 acid is heated with water in a fractionating-flask connected 
 with a condenser. The acid volatilizes with the steam, 
 and condenses as a white, flocculent precipitate, the distillate 
 having an acid reaction. 
 
 4. Solubility of Benzoic Acid in Water. 1 g. of benzole 
 acid is heated gently in a test-tube with 1 c.c. of water. At 
 first, two liquid layers are formed, and complete solution of 
 the acid is only attained by boiling with a large excess of water. 
 On cooling, it crystallizes in leaflets. 
 
 5. Ethyl Benzoate. 1 g. of benzole acid is warmed with 5 
 c.c. of absolute alcohol and a few drops of concentrated sul- 
 phuric acid. The ethyl benzoate formed is characterized by a 
 peppermint-like odour. 
 
 6. Benzanilide. A few cubic centimetres of water are 
 added to 1 c.c. of aniline, and then alternately small quanti- 
 ties of potassium hydroxide and benzoyl chloride drop by drop. 
 The mixture is agitated constantly, care being taken to maintain 
 it alkaline. Finally, the alkaline liquid is agitated till the 
 odour of benzoyl chloride is no longer perceptible. The white 
 precipitate of benzanilide is collected on a filter, washed with 
 water till the filtrate is no longer alkaline, and crystallized 
 from alcohol. M. P. 158. 
 
 7. Benzamide. 3 g. of ammonium carbonate are reduced 
 to fine powder in a mortar, and benzoyl chloride added drop 
 by drop, the mixture being stirred continuously with the pes- 
 tle till the odour of benzoyl chloride is no longer perceptible. 
 It is lixiviated with cold water to remove ammonium chloride 
 and carbonate, and the residue dissolved in a small quantity 
 of hot water. On cooling, benzamide crystallizes out. M. P. 
 128. 
 
 This substance is identified by warming with dilute potas- 
 sium hydroxide. Ammonia is evolved, and addition of hydro- 
 chloric acid to the alkaline solution precipitates benzole acid. 
 
xxx.] BENZALDEHYDE 59 
 
 XXX. BENZALDEHYDE. 
 (314 and 315.) 
 
 1. Silver-mirror Test. 2 drops of benzaldehyde are added 
 to an ammoniacal solution of silver nitrate, prepared as de- 
 scribed in X., 2. Gentle heating in a water -bath produces a 
 silver mirror. 
 
 2. Benzaldehydephenylhydrazone. A few drops of benz- 
 aldehyde are added to a solution of phenylhydrazine in sul- 
 phurous acid. Benzaldehydephenylhydrazone is precipitated, 
 and by crystallization from alcohol is obtained in large, fine 
 crystals, melting at 152. 
 
 3. Sulphite Compound of Benzaldehyde. A cubic centi- 
 metre of benzaldehyde is agitated with a very concentrated 
 solution of sodium hydrogen sulphite. The crystalline sul- 
 phite compound is precipitated, and the odour of benzaldehyde 
 ceases to be perceptible. On warming with water, the sul- 
 phite derivative is decomposed, and the benzaldehyde liberated. 
 
 4. Action of Alcoholic Potash on Benzaldehyde. On mix- 
 ing 1 c.c. of benzaldehyde with 5 c.c. of a ten per cent, solu- 
 tion of alcoholic potash, heat is developed, and the liquid 
 solidifies owing to the precipitation of potassium benzoate. 
 The crystals are collected on a filter, washed with a small 
 quantity of alcohol, and dissolved in water. Addition of 
 hydrochloric acid precipitates benzole acid. The alcoholic 
 filtrate contains benzyl alcohol (325). 
 
 5. Oxidation of Benzaldehyde. a) By the Air. A few 
 drops of benzaldehyde are placed upon a glass plate, and allowed 
 to spread. On the following day, the aldehyde will be found 
 to have changed completely into crystals of benzole acid. 
 
 6) By Potassium Permanganate. A few drops of benz- 
 aldehyde are heated with an aqueous solution of potassium 
 permanganate. Manganese dioxide is precipitated, the aide- 
 
60 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxxi. 
 
 hyde being oxidized to benzole acid, which remains dissolved 
 as potassium benzoate. When the odour of benzaldehyde is 
 no longer perceptible, two drops of alcohol are added to reduce 
 the excess of potassium permanganate, and the colourless 
 liquid filtered. On acidifying the filtrate, benzole acid is 
 precipitated. 
 
 XXXI. BENZENE HOMOLOGUES WITH SUBSTITUTED 
 SIDE-CHAINS. 
 
 (321-325.) 
 
 1. Saponification of Benzyl Chloride by Potassium or Sodium 
 Hydroxide. 1 c.c. of benzyl chloride is warmed for a short 
 time with 10 c.c. of ten per cent, alcoholic potash or soda, 
 and the mixture diluted with a large excess of water. If the 
 heating has been of sufficient duration, no benzyl chloride 
 separates. After acidifying with nitric acid, the solution 
 gives with silver nitrate a heavy precipitate of silver chloride. 
 
 2. Benzyl Iodide. A small quantity of benzyl chloride is 
 heated with an alcoholic solution of potassium iodide in a fume- 
 cupboard. Benzyl iodide is formed, and gives off an extremely 
 irritating odour, productive of tears. 
 
 3. Action of Light on Toluene in Presence of Bromine. 
 10 c.c. of toluene are poured into a test-tube, and a few drops 
 of bromine added. In daylight, near a window, the mixture 
 becomes decolorized in a few minutes, gaseous hydrobromic 
 acid being evolved. 
 
 4. Resinification of Benzyl Alcohol. Concentrated sulphuric 
 acid is added to a few drops of benzyl alcohol. An ester is 
 not formed, but the alcohol becomes resinified. 
 
xxxm.] POLYSUBSTITUTED BENZENE DERIVATIVES 61 
 
 XXXII. COMPOUNDS CONTAINING AN UNSATURATED 
 SIDE-CHAIN. 
 
 (328.) 
 
 i. Oxidation of Cinnamic Acid by Potassium Permanganate. 
 
 0-1 g. of cinnamic acid is agitated with water, and several 
 drops of a one per cent, solution of potassium permanganate 
 added. The colour of the solution is discharged, a precipitate 
 of hydrated manganese dioxide formed, and the liquid acquires 
 an odour of benzaldehyde. 
 
 XXXIII. POLYSUBSTITUTED BENZENE DERIVATIVES. 
 
 (329-350.) 
 
 1. Reactivity of the Halogen Atom in Halogen Nitro-com- 
 pounds. 0-1 g. of picryl chloride is boiled with water for a 
 few minutes. After acidification with nitric acid, the presence 
 of chlorion is detected by addition of a solution of silver 
 nitrate. 
 
 2. ra-Dinitrobenzene. 1-5 c.c. of benzene are added drop 
 by drop to a mixture of 5 c.c. of concentrated sulphuric acid 
 and 5 c.c. of fuming nitric acid, the liquid being agitated thor- 
 oughly during the process. The solution is heated for a few 
 minutes, allowed to cool, and poured into water. m-Dinitro- 
 benzene is precipitated, and is freed from a small percentage 
 of the ortho-compound and traces of the para-compound by 
 crystallization from alcohol. M. P. 90. 
 
 3. Reactivity of One Nitro-group in i :3:5-Trinitrobenzene. 
 0-1 g. of l:3:5-trinitrobenzene is dissolved in boiling methyl 
 alcohol, and a few drops of sodium-methoxide solution are 
 added. The liquid immediately becomes blood-red, and, 
 after an interval, long colourless needles of 3:5-dinitroanisole 
 separate. 
 
62 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxxm. 
 
 4. Nitrophenols. 3 c.c. of phenol, liquefied by addition 
 of a small quantity of water, are added slowly to 18 c.c. of 
 nitric acid of 1-17 specific gravity. During the process, the 
 mixture is cooled, and agitated vigorously. A heavy, black 
 oil separates from the aqueous liquid. After washing with 
 water in a small separating-funnel, the oil is distilled with 
 steam (III., 2). o-Nitrophenol distils, and can be identified 
 by its odour, and by its yellow crystals melting at 44. The 
 residue in the flask contains p-nitrophenol. 
 
 5. Coloured Salts of p-Nitrophenol. 0-1 g. of colourless 
 p-nitrophenol is dissolved in a dilute solution of sodium 
 hydroxide. The liquid has an intense yellow colour. 
 
 6. Picric Acid. On carefully heating 0-1 g. of picric acid 
 in a test-tube, the acid melts and sublimes; more rapid heating 
 causes explosive decomposition, leaving a residue of carbon. 
 At the same time, an odour resembling that of nitrobenzene 
 becomes perceptible. 
 
 7. Potassium Picrate. Potassium-hydroxide solution is 
 added to an alcoholic solution of 0-5 g. of picric acid. Bright- 
 yellow potassium picrate is precipitated, collected on a filter- 
 paper, and dried by exposure to the air. The dry salt is 
 exploded by percussion, and by heating on a platinum or 
 porcelain crucible-lid. Only a very minute quantity of the salt 
 must be used for this experiment. 
 
 8. Taste of Picric Acid. 0-1 g. of picric acid is dissolved in 
 water; the solution thus obtained has a very bitter taste. 
 
 9. Dyeing with Picric Acid. A woollen thread immersed 
 in the liquid is soon dyed bright-yellow. 
 
 10. ^soPurpuric Acid. An aqueous solution of potassium 
 cyanide is added to one of picric acid. A purple coloration, 
 due to the formation of the potassium salt of zsopurpuric acid, 
 is produced. 
 
 11. Chloropicrin. O5 g. of picric acid is warmed carefully 
 with a solution of bleaching-powder. The pungent odour of 
 chloropicrin, CClsNC^, becomes perceptible. 
 
XXXIIL] POLYSUBSTITUTED BENZENE DERIVATIVES 63 
 
 12. lonization of Picric Acid in Aqueous Solution. On 
 
 warming a small quantity of picric acid with light petroleum 
 in a test-tube, a colourless solution is obtained, the acid not 
 being ionized in this solvent. When, however, this colourless 
 solution is agitated with a small quantity of water, the latter 
 acquires the deep-yellow colour characteristic of the anion of 
 picric acid. 
 
 13. Tests for Catechol, Resorcinol, and Quinol. With a 
 drop of ferric chloride, aqueous solutions of catechol and resor- 
 cinol give a green and a deep-violet coloration respectively. 
 With bromine-water, resorcinol yields a precipitate of tribromo- 
 resorcinol. 
 
 Solutions of catechol and resorcinol are made alkaline with 
 sodium hydroxide. They acquire a dark colour immediately. 
 
 Addition of ammonium hydroxide to a solution of quinol 
 turns it red-brown. 
 
 14. Reducing Power of the Dihydroxybenzenes. At ordinary 
 temperature, solutions of catechol and quinol reduce a solu- 
 tion of silver nitrate, with precipitation of metallic silver as 
 a black powder. Quinol also reduces FEHLING'S solution. 
 
 15. Pyrogallol. On carefully heating 5 g. of well-dried 
 gallic acid in a retort, carbon dioxide which can be identified 
 by the lime-water test is evolved, and pyrogallol sublimes. 
 The latter is dissolved in water, and the solution divided 
 into three parts. 
 
 When silver-nitrate solution is added to one, metallic 
 silver is precipitated. 
 
 Addition of a drop of ferric chloride to the second produces 
 an intense bluish-black coloration. 
 
 The third portion is transferred to a thick-walled test-tube, 
 potassium hydroxide added, the tube closed with a closely- 
 fitting cork or rubber-stopper, and the mixture vigorously 
 agitated. The oxygen in the tube is absorbed, the pyrogallol- 
 solution turning brown. On removing the stopper under 
 water, the latter rises in the tube. 
 
64 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxxm. 
 
 1 6. Benzoquinone. A small quantity of potassium- 
 dichromate solution and a drop of concentrated sulphuric 
 acid are added to a drop of aniline in a dish. The pungent 
 odour of benzoquinone is perceived. 
 
 17. Quinhydrone. A solution of ferric chloride is added 
 to an aqueous solution of quinol. After an interval of time, 
 quinhydrone crystals of beautiful metallic lustre separate. 
 
 18. Difference in Basicity of the Three Nitroanilines. 0-5 g. 
 of o-nitroaniline, w-nitroaniline, and p-nitroaniline respectively 
 are dissolved in about the same quantity of concentrated 
 sulphuric acid, and the solutions poured into about 100 c.c. of 
 water. o-Nitroaniline separates almost completely, indicating 
 a high degree of hydrolysis; p-nitroaniline gives a yellow 
 colour, due to slight hydrolysis; the solution of ra-nitroani- 
 line is colourless, owing to absence of hydrolysis. 
 
 19. Reactivity of the Amino-group in Picramide. 0*1 g. 
 of picramide is warmed with a dilute solution of sodium 
 hydroxide. The formation of ammonia is proved by testing 
 with a moistened strip of red litmus-paper. 
 
 20. p-Diazobenzenesulphonic Acid. 1-7 g. of sulphanilic 
 acid, NH^-CeH/t-SCbOH (1 : 4), are dissolved by heating with 
 25 c.c. of two per cent, sodium hydroxide. A concentrated 
 aqueous solution of 1 g. of sodium nitrite is added, and the 
 mixture poured into excess of cold, dilute sulphuric acid. 
 After an interval, p-diazobenzenesulphonic acid is precipitated 
 as a sand-like, crystalline powder. 
 
 21. Oxidation of Aminophenols. 0-1 g. of p-aminophenol 
 hydrochloride is dissolved in water, and a solution of sodium 
 hydroxide added. Owing to atmospheric oxidation, the liquid 
 rapidly becomes brown in colour. 
 
 22. Test for Nitrous Acid with ?7?-Phenylenediamine. 
 A drop of a solution of sodium nitrite and a drop of dilute 
 sulphuric acid are added to 10 c.c. of a dilute solution of 
 m-phenylenediamine. The liquid becomes brown, Bismarck- 
 brown or vesuvine being formed. 
 
xxxm.] POLYSUBSTITUTED BENZENE DERIVATIVES 65 
 
 23. Dyeing with Aminoazobenzene. An alcoholic solution 
 of aminoazobenzene is diluted with water, and a few drops of 
 dilute hydrochloric acid added. A woollen thread immersed 
 in the liquid for a quarter of an hour is dyed yellow, and the 
 colour cannot be removed by washing with water. 
 
 24. Reduction of Aminoazobenzene. A small quantity of 
 aminoazobenzene hydrochloride is brought into contact with 
 tin and hydrochloric acid. It is decolorized, yielding p- 
 phenylenediamine and aniline. The mixture is made strongly 
 alkaline with sodium hydroxide, and distilled, using a condenser. 
 The presence of aniline in the distillate can be proved by the 
 bleaching-powder test (XXVII., 5). 
 
 25. Taste of "Saccharin." 0-1 g. of "saccharin" is 
 dissolved in 1 litre of water, and 30 g. of sucrose are dissolved 
 in a similar volume. When tasted, both solutions are found 
 to have nearly the same degree of sweetness. 
 
 26. Salicylic Acid. 0-5 g. of salicylic acid is heated gently 
 in a test-tube; it melts, and sublimes. On heating to a higher 
 temperature, it decomposes partly into carbon dioxide and 
 phenol, the characteristic odour of the latter becoming per- 
 ceptible. 
 
 27. Action of Bromine-water on Salicylic Acid. Bromine- 
 water added to a saturated solution of salicylic acid gives a 
 precipitate of the formula C6H 2 Br 3 *OBr. 
 
 28. Identification of Salicylic Acid and Phenol. Ferric 
 chloride is added to alcoholic and aqueous solutions of salicylic 
 acid and phenol respectively. Salicylic acid gives the violet 
 coloration in both solvents, phenol only in water. 
 
 29. Calcium Salicylate. 0-5 g. of salicylic acid is added to a 
 mixture of calcium-chloride solution and ammonium hydroxide. 
 On heating, calcium salicylate, CyH-tOsCajH^O, is precipitated. 
 
 30. Manufacture of Ink. 1 g. of gallic acid is dissolved 
 in water, and a solution of ferrous sulphate added. When 
 employed as an ink, this liquid leaves a very faint mark on the 
 paper, but on drying the writing becomes black. 
 
66 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxxm. 
 
 31. Action of Tannin on Gelatin. A solution of tannin is 
 added to one of gelatin. The gelatin is precipitated. 
 
 32. Test for Tannin. A dilute solution of tannin is turned 
 dark-violet by a drop of ferric chloride. A piece of oak-bark 
 or cinchona-bark, an unroasted coffee-bean, and part of a 
 gall-nut are extracted with boiling water in different dishes. 
 The presence of tannin in all these solutions can be proved by 
 the ferric-chloride test. 
 
 33. Action of Tannin on Quinine. On addition of a solution 
 of tannin to one of quinine hydrochloride, the alkaloid is pre- 
 cipitated. 
 
 34. Interaction of Proteins and Tannin. 10 c.c. of milk are 
 freed from casein and fat by the method described in XVIII., 
 17. The presence of proteins in the nitrate can be proved by 
 adding tannin, an insoluble compound of the proteins and 
 tannin being precipitated. 
 
 35. Decomposition of Anthranilic Acid. 0-2 g. of dry 
 anthranilic acid is heated in a test-tube. Part of it sublimes, 
 and part decomposes with evolution of carbon dioxide, and 
 formation of oily drops of aniline. 
 
 36. Phthalic Anhydride. 0*1 g. of phthalic acid is heated 
 in a dish, covered with a watch-glass, on a sand-bath. Long 
 needles of phthalic anhydride sublime. 
 
 37. Fhioresce'in. Some crystals of phthalic anhydride and a 
 like quantity of resorcinol are heated for a few minutes with 1 c.c. 
 of concentrated sulphuric acid. To prevent the liquid becoming 
 dark-coloured, the heating must not be too prolonged, or the 
 temperature too high. On dissolving the mixture in 100 c.c. of 
 water and adding sodium hydroxide, a beautifully fluorescent, 
 yellowish-green solution containing fluorescein is obtained. 
 
 38. Phenolphthalein. A mixture of like quantities of 
 phthalic anhydride and phenol is w r armed with concentrated 
 sulphuric acid, phenolphthalein being formed. When this is 
 added to a dilute solution of a caustic alkali, a red coloration 
 is produced. 
 
xxxiv.] HYDEOCYCLIC COMPOUNDS 67 
 
 39. Red Anion of Phenolphthalein. A few milligrammes of 
 phenolphthalem are dissolved in absolute alcohol containing a 
 trace of calcium hydroxide in suspension; the liquid remains 
 colourless. On dilution with water, the calcium compound of 
 the phthalei'n is ionized, with production of a red colour 
 
 XXXIV. HYDROCYCLIC COMPOUNDS. 
 (365-370.) 
 
 1. Artificial Camphor. American or German oil of turpen- 
 tine is dried by calcium chloride, poured off, and distilled. 
 Being turbid, the first few cubic centimetres of the distil- 
 late are rejected. Dry hydrochloric-acid gas, prepared by the 
 method of IX., 15, is led into 10 c.c. of the dry, quite clear 
 turpentine, the flask being cooled by ice. After some time, 
 transparent crystals of pinene hydrochloride or " artificial 
 camphor/ 7 CioHi6,HCl, are deposited. The mother-liquor is 
 poured off, and the crystals dried by pressing between layers 
 of filter-paper. In odour and appearance pinene hydrochloride 
 resembles camphor. 
 
 2. Volatility of Camphor with Steam. A piece of camphor 
 is placed in water in a fractionating-flask connected with a 
 condenser. On heating, the camphor passes over with the 
 steam. 
 
 3. Camphor and Water. A piece of camphor thrown upon 
 the surface of water acquires a rotatory motion, due to v dis- 
 parity of the vapour-tension for the different crystal faces. 
 
 4. Camphoric Acid. 2 g. of camphor arc heated in a flask 
 with dilute nitric acid for some minutes, and evaporated almost 
 to dry ness in a porcelain dish. The residue is diluted with 
 water, made alkaline with sodium hydroxide, and the undis- 
 solved portion filtered off. If the filtrate is not too dilute, 
 hydrochloric acid precipitates camphoric acid. 
 
68 LABORATOEY MANUAL OF ORGANIC CHEMISTRY [xxxv. 
 
 XXXV. BENZENE-NUCLEI LINKED TOGETHER BY 
 CARBON. 
 
 (371-374.) 
 
 1. Rosolic Acid. A mixture of 2 c.c. of phenol, 0-5 g. 
 of oxalic acid, and 5 c.c. of concentrated sulphuric acid is 
 heated in a test-tube. It acquires a red colour. On pouring 
 the liquid into water, and making it alkaline with potassium 
 hydroxide, a dark-red solution is obtained, containing the 
 potassium salt of rosolic acid. 
 
 2. Magenta. 1 c.c. of aniline is heated in a test-tube with 
 1 g. of p-toluidine and 0*5 g. of mercuric chloride, magenta 
 being formed. On pouring the liquid into water containing 
 a small quantity of hydrochloric acid, a deep-red solution is 
 produced. 
 
 3. Action of Concentrated Hydrochloric Acid on a Solution 
 of Magenta. Concentrated hydrochloric acid is added to part 
 of the solution obtained in 2. The liquid becomes yellow, 
 owing to the formation of the hydrochloride of the rosaniline 
 base containing 3HC1. When this is poured into a large quan- 
 tity of water, the red colour is restored. 
 
 4. Colour-base. Excess of solution of ammonium or potas- 
 sium hydroxide is added to another portion of the magenta 
 solution. The colour-base is formed, and the liquid decolorized. 
 
 5. Leuco-base. A third portion of the magenta solution is 
 treated with zinc and hydrochloric acid, without the applica- 
 tion of heat. The leuco-base is formed, and the colour dis- 
 charged, 
 
xxxvi.] CONDENSED BENZENE-NUCLEI 69 
 
 XXXVI. CONDENSED BENZENE-NUCLEI. 
 
 (377-385.) 
 
 1. Action of Heat on Naphthalene. 0*5 g. of naphthalene is 
 heated in a test-tube. It melts, and sublimes readily. 
 
 2. Naphthalene Picrate. 3 c.c. of a concentrated ether 
 solution of picric acid are mixed with a like volume of a con- 
 centrated solution of naphthalene in that solvent. A yellow, 
 crystalline precipitate of naphthalene picrate is produced. 
 
 3. Naphthalenemonosulphonic Acids. A mixture of 0-5 g. 
 of naphthalene and 2 c.c. of concentrated sulphuric acid is 
 heated in a test-tube for a few minutes, allowed to cool, and 
 poured into water. On treatment with barium carbonate by 
 the method of VI., 2, the presence of the dissolved sulphonic 
 acids is proved. 
 
 4. a-Nitronaphthalene. 1 g. of naphthalene is dissolved 
 in 5 c.c. of concentrated nitric acid, and the solution poured 
 into water. The precipitated yellow a-nitronaphthalene is 
 crystallized from a small quantity of alcohol, being obtained 
 in yellow needles, melting at 61. 
 
 5. Crude Naphthol. 0-5 g. of naphthol is agitated with 
 water; only a small quantity dissolves. On addition of 
 potassium or sodium hydroxide, a solution is obtained, from 
 which carbon dioxide reprecipitates the naphthol. 
 
 6. Martius's Yellow. 1 g. of a-naphthol is dissolved in 3 
 c.c. of concentrated sulphuric acid, and the solution poured into 
 3 c.c. of concentrated nitric acid. When this mixture is diluted 
 with water, dinitro-a-naphthol is precipitated. It is filtered 
 off, washed, transferred to a vessel containing water, and dis- 
 solved by addition of a small quantity of sodium hydroxide, 
 with formation of the sodium salt, Martius's yellow. A 
 woollen thread dipped into this solution becomes dyed deep- 
 vellow. 
 
70 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxxvi. 
 
 7. Naphthylamines. 0*5 g. of a-naphthylamine is dis- 
 solved in dilute hydrochloric acid. With ferric chloride this 
 solution gives a blue precipitate. A similar solution of pure 
 /3-naphthylamine does not react thus. 
 
 8. Congo-red. A few centigrammes of congo-red are placed 
 in water, and a drop of concentrated hydrochloric acid added. 
 The liberated acid turns the liquid blue; addition of an alkali 
 restores the red colour. 
 
 9. Naphthionic Acid. A mixture of 1 g. of a-naphthyla- 
 mine and 3 c.c. of concentrated sulphuric acid is heated in a 
 test-tube for a few minutes, and poured into water. On mak- 
 ing the liquid alkaline with sodium hydroxide, it exhibits an 
 intense reddish-blue fluorescence, resulting from the formation 
 of sodium naphthionate. 
 
 10. Oxidation of Anthracene by Chromic Acid. Small 
 quantities of an acetic-acid solution of chromic acid are added 
 to a solution of 3 g. of anthracene in this solvent, until the 
 energetic reaction has ceased. The liquid is poured into water, 
 and the precipitated anthraquinone collected on a filter. 
 
 11. Test for Anthraquinone. A few centigrammes of an- 
 thraquinone are heated in a test-tube with zinc-dust and 
 sodium hydroxide, a deep blood-red solution of anthraquinol 
 being formed. On agitating this solution with air, the colour 
 is discharged. 
 
 12. Potassium Salt of Alizarin. A few centigrammes of 
 alizarin are placed in water, but the substance does not dissolve. 
 Cn addition of a dilute solution of potassium hydroxide, the 
 very intense deep-blue colour of the potassium salt is developed. 
 
xxxvii.] HETEROCYCLIC COMPOUNDS 71 
 
 XXXVII. HETEROCYCLIC COMPOUNDS. 
 (387-399.) 
 
 1. Pyridine. Some drops of pyridine are added to a few 
 cubic centimetres of water, the base dissolving completely. 
 The solution has an alkaline reaction. 
 
 2. Action of Pyridine on Ferric Chloride. The aqueous 
 solution of pyridine gives with one of ferric chloride a precipi- 
 tate of ferric hydroxide. 
 
 3. Action of Pyridine on Mercuric Chloride. A solution of 
 mercuric chloride added to a pyridine solution precipitates a 
 white, crystalline compound of pyridine and mercuric chloride. 
 
 4. Test for Pyridine. Hydrochloroplatinic acid, H^PtCle, 
 is added to a small quantity of a solution of pyridine; no 
 precipitate is formed. On boiling the mixture for a short 
 time, a yellow powder of the formula PtCL^CsHsN^ is 
 deposited. This test is characteristic for pyridine. 
 
 5c Action of the Alkaloid-reagents on Pyridine. The alkaloid- 
 reagents (407) among them tannin, phosphomolybdic acid, 
 and picric acid precipitate pyridine from solution. 
 
 6. Stability of Pyridine towards VON BAEYER'S Reagent. A 
 solution of potassium permanganate and sodium- carbonate 
 is added to one of pyridine. The violet-red colour is not 
 altered. 
 
 7. Stability of Pyridine towards Oxidizing Agents. A solu- 
 tion of pyridine is heated with sodium or potassium dichromate 
 and concentrated sulphuric acid. The colour of the solution 
 undergoes no change. 
 
 8. Pyrrole-red. Water is added to a small quantity of 
 " Dippel's oil " (387) in a test-tube, and the mixture boiled. 
 A wood-splint moistened with concentrated hydrochloric acid 
 becomes coloured red by the vapour, pyrrole-red being formed. 
 
 9. Indophenin-reaction. A cubic centimetre of crude ben- 
 zene and a like volume of concentrated sulphuric acid are 
 
72 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxxvm. 
 
 brought into contact with a fragment of isatin. In presence 
 of thiophen, the layer of sulphuric acid develops an intense 
 blue colour. 
 
 10 c.c. of crude benzene are agitated repeatedly with warm, 
 concentrated sulphuric acid, about 2 c.c. being used for each 
 operation. The benzene is separated, and tested by the indo- 
 phenin-reaction. Either the blue coloration is not produced, 
 or it is much less pronounced than in the first experiment. 
 
 10. Tests for Antipyrine. A solution of antipyrine is 
 turned red by ferric chloride, bluish-green by potassium or 
 sodium nitrite and acetic acid. 
 
 XXXVIII. CONDENSATION-PRODUCTS OF BENZENE AND 
 HETEROCYCLIC NUCLEI. 
 
 (400-405.) 
 
 1. SKRAUP'S Synthesis of Quinoline. A mixture of 4 c.c. of 
 aniline, 12 c.c. of glycerol, 2-5 c.c. of nitrobenzene, and 6 c.c. 
 of sulphuric acid is heated carefully in a flask till the reaction 
 begins, the burner being then removed. When it has moder- 
 ated, the heating is resumed, and continued for five or ten 
 minutes. The liquid is cooled, poured into water, and dis- 
 tilled with steam (III., 2) after addition of excess of sodium 
 hydroxide. The turbidity of the distillate is caused by the 
 presence of minute drops of quinoline. The characteristic 
 odour of the base is perceived. 
 
 2. Quinoline Hydrochloride. On addition of hydrochloric 
 acid to the distillate obtained in i, the liquid becomes clear, 
 soluble quinoline hydrochloride being formed. Sodium or 
 potassium hydroxide reprecipitates the quinoline in oily drops. 
 
 3. Quinoline Picrate. With a solution of quinoline hydro- 
 chloride, a saturated, aqueous solution of picric acid gives a 
 yellow, amorphous precipitate of quinoline picrate. 
 
xxxix.] ALKALOIDS 73 
 
 4. Quinoline Bichromate. With quinoline salts, potassium 
 dichromate gives a yellow, crystalline precipitate of quinoline 
 dichromate, (CgHrN^I^C^Or. 
 
 5. Volatility of Indigo. On heating 0-1 g. of indigo in a 
 test-tube, a violet vapour is formed. 
 
 6. Solubility of Indigo in Nitrobenzene. 0-1 g. of indigo 
 is heated with a small quantity of nitrobenzene. It dissolves, 
 and, on cooling, crystallizes. 
 
 7. Indigosulphonic Acid. 0*1 g. of indigo is dissolved in 
 1 c.c. of fuming sulphuric acid. Indigosulphonic acid is formed, 
 so that the indigo is not reprecipitated when the solution is 
 poured into water. 
 
 8. Oxidation of Indigo to Isatin. The solution of indigo- 
 sulphonic acid obtained in 7 is warmed with a small quantity of 
 concentrated nitric acid. It is decolorized, and isatin formed. 
 
 9. "Vat-dyeing." 0-1 g. of powdered indigo is heated 
 with a solution of sodium hyposulphite, Na2S204 (" Inorganic 
 Chemistry/ 7 83). Sodium thiosulphate, miscalled " sodium 
 hyposulphite/ 7 must not be used. A strip of linen or cotton is 
 immersed in the solution of indigo-white, and hung up to dry. 
 The oxygen of the atmosphere oxidizes the indigo-white to 
 indigo-blue. 
 
 XXXIX. ALKALOIDS. 
 (406-415.) 
 
 1. Alkaloid-reagents. A solution of an alkaloid, such as 
 quinine hydrochloride or sulphate, is tested with solutions of 
 the ordinary alkaloid-reagents; for example, tannin, phospho- 
 molybdic acid, mercuric potassium iodide, and a solution of 
 iodine in one of potassium iodide. With each a precipitate is 
 formed. 
 
 2. Nicotine. 10 g. of tobacco are boiled with 100 c.c. of 
 water containing a small quantity of sulphuric acid. After 
 
74 LABORATORY MANUAL OF ORGANIC CHEMISTRY [xxxix. 
 
 filtering, the filtrate is rendered alkaline, and distilled. The 
 distillate contains nicotine, and yields precipitates with plati- 
 num chloride, mercuric chloride, and a potassium-iodide solu- 
 tion of iodine. 
 
 3. Fluorescence of Quinine-sulphate Solution. 0-1 g. of 
 quinine sulphate is dissolved in water containing sulphuric acid. 
 The solution exhibits a blue fluorescence. 
 
 4. Action of Chlorine on Quinine Salts. Chlorine-water is 
 added to a solution of a quinine salt until the liquid smells 
 strongly of the gas. On addition of ammonium hydroxide, an 
 emerald-green coloration is produced. 
 
 5. Test for Strychnine. A crystal of strychnine nitrate is 
 placed in a porcelain dish, and a few drops of concentrated sul- 
 phuric acid added. A small crystal of potassium dichromate 
 produces with this liquid a very intense bluish-violet colour. 
 
 6. Test for Brucine. A small quantity of brucine yields a 
 red coloration with concentrated nitric acid; on the applica- 
 tion of gentle heat, the colour changes to yellow. Dilution with 
 water, and addition of ammonium sulphide renders the yellow 
 solution violet. 
 
INDEX. 
 
 The basis of the arrangement of this index is threefold: 
 
 (1) The numbers refer to pages. 
 
 (2) In all instances of possible ambiguity as to the identity of the principal 
 references, they are given in old-style figures. 
 
 (3) Where a reference is a sub-division of a principal heading, it is indented 
 one em space for each word of the principal heading not repeated. Portions 
 of words followed by a hyphen are treated as words for the purposes of .this 
 arrangement. 
 
 A. 
 
 Acetal, 21. 
 
 Acetaldehyde, 21, 32. 
 Acetamide, 2, 12. 
 Acetate, Acetoferric, 18. 
 
 Basic ferric, 18. 
 
 Calcium, 22. 
 
 Ethyl, 20, 42. 
 
 Lead, 4, 5, 19, 29, 42. 
 
 Potassium, 38. 
 
 Silver, 17. 
 
 Sodium, 7, 17, 18, 56. 
 Acetic acid, 10, 17, 18, 20, 23, 26, 
 38, 54. 
 
 Tests for, 17, 18, 23. 
 Acetoanilide, 54. 
 Aceto-ferric acetate, 18. 
 Acetone, 22, 23, 34. 
 
 Test for. 22. 
 Acetylene, 24, 25. 
 
 Copper. 24. 
 
 Silver, 24. 
 
 Acid, Acetic, 10, 17, 18, 20, 23, 26, 
 38, 54. 
 
 Amalic, 50. 
 
 Anthranilic, 66. 
 
 Benzenemonosulphonic, 50. 
 
 Benzole, 57, 58, 59, 60. 
 
 n-Butyric, 19. 
 
 Acid, Camphoric, 67. 
 Carbamic, 49. 
 Carbolic. See phenol. 
 Cinnamic, 61. 
 Citric, 33, 34. 
 Cyanic, 46. 
 Cyanuric, 48. 
 
 p-Diazobenzensulphonic, 64. 
 Ethylsulphuric, 10, 11. 
 Ferrocyanic, 44. 
 Formic, 15-17, 27, 32, 34. 
 Gallic, 63, 65. 
 Glucosesulphuric, 37. 
 Glyoxylic, 43. 
 Hydrocyanic, 43, 44. 
 Indigosulphonic, 73. 
 Lactic, 32. 
 I'flpvulic, 37. 
 Methylnitrolic, 14. 
 Mucic, 38, 39. 
 Naphthionic, 70. 
 Oleic, 25. 
 
 Oxalic, 7, 15, 16, 27, 28-31, 47, 68. 
 Phthalic, 66. 
 
 Picric, 53, 62, 63, 69, 71, 72. 
 Propionic, 15. 
 isoPurpuric, 62. 
 Racemic, 33. 
 Rosolic, 68. 
 Salicylic, 6, 65. 
 
 75 
 
76 
 
 INDEX 
 
 Acid, Succinic, 31. 
 
 Sulphanilic, 64. 
 
 Tartaric, 32, 33. 
 
 Uric, 49, 50. 
 
 Xanthic, 47. 
 Acids, CnH 2 nO 2 , Saturated, 15-20. 
 
 Higher fatty, 19. 
 
 Hydroxy-, 32-34. 
 
 Monobasic unsaturated, 25, 26. 
 
 Naphthalenemonosulphonic, 69. 
 
 Saturated dibasic, 28-32. 
 
 Volatile fatty, 19. 
 Acraldehyde, 28. 
 ADAMKIEWICZ'S reaction, 43. 
 Albumin, Egg-, 2-4, 22, 42, 43. 
 Albuminate, Copper, 43. 
 Alcohol, Allyl, 27, 28. 
 
 Benzyl, 59, 60. 
 
 Ethyl, 5, 8-10, 11, 18, 20, 21, 
 23, 26, 27, 31, 42, 47, 58. 
 
 Methyl, 22, 29. 
 
 Tests for ethyl, 10, 27, 58. 
 
 water in, 9, 10. 
 Alcohols, Aldehyde- See sugars. 
 
 C n H 2 n+i-OH,8-10. 
 
 Keto-. See sugars. 
 Aldehyde-resin, 21. 
 Aldehydes, 21, 22. 
 Aldehy do-alcohols. See sugars. 
 Alizarin, 70. 
 
 Potassium salt of, 70. 
 Alkaloid-reagents, 71, 73. 
 Alkaloids, 73, 74. 
 Alkyl halides, 10. 
 Allot^ropic modifications of carbon, 
 
 4,5. 
 
 Alloxantine, 49. 
 Allyl alcohol, 27, 28. 
 Almond oil, 25, 26. 
 Aluminium carbide, 7. 
 Amalic acid, 50. 
 Amines, 12-14, 53-55. 
 
 Test for primary, 12. 
 
 Amino-azobenzene, 65. 
 
 hydrochloride, 65. 
 
 -phenol, p-, 64. 
 Ammonia copper cyanurate, 48. 
 
 cyanate, 47. 
 
 dithiocarbamate, 49. 
 
 formate, 44. 
 
 oxalate, 29, 30. 
 
 purpurate, 49. 
 
 Ammonium thiocyanate, 3, 49. 
 
 urate, 49. 
 Amylene, 24. 
 Amyloid, 41. 
 Analysis of carbon compounds, 
 
 Qualitative, 1-4. 
 
 Aniline, 36, 42, 53, 54, 55, 56, 58, 
 64, 66, 72. 
 
 -black, 54. 
 
 hydrochloride, 57. 
 
 Tests for, 54. 
 Anthracene, 70. 
 Anthranilic acid, 66. 
 Anthraquinol, 70. 
 Anthraquinone, 70. 
 
 Test for, 70. 
 
 Antifebrine. See acetoanilide. 
 Antipyrine, 72. 
 Artificial camphor, 67. 
 Azobenzene, 55. 
 
 B. 
 
 BAEYER'S test for the double bond, 
 
 VON, 24, 25, 50, 71. 
 Barium alkoxide of starch, 40. 
 
 ethylsulphate, 11. 
 
 glucosesulphate, 37. 
 
 succinate, 31. 
 
 trithiocarbonate, 47. 
 BEILSTEIN'S test, 3. 
 Benzaldehyde, 59, 60. 
 
 -phenylhydrazone, 59. 
 Benzamide, 58. 
 Benzanilide, 58. 
 Benzene, 6, 7, 50, 51, 61, 71, 72. 
 
 -diazonium chloride, 56. 
 
 -monosulphonic acid, 50. 
 
 -sulphonate, Sodium, 50, 52, 57. 
 Benzidine sulphate, 55. 
 Benzoate, Calcium, 51. 
 
 Ethyl, 58. 
 
 Potassium, 59, 60. 
 Benzoic acid, 57, 58, 59, 60. 
 Benzonitrile, 57. 
 Benzoquinone, 64. 
 Benzoyl chloride, 58. 
 Benzyl alcohol, 59, 60. 
 
 chloride, 60. 
 
 iodide, 60. 
 Bismarck-brown, 64. 
 
INDEX 
 
 77 
 
 Biuret, 48. 
 
 -reaction, 43, 48. 
 Boiling-point, Determination of, 6, 
 
 7. 
 
 Bone-charcoal, 4, 5 . 
 Bran, 36. 
 Brucine, 74. 
 
 Test for, 74. 
 BUNSEN, 48. 
 Butter, 18, 19. 
 Butyric acid, n-, 19. 
 
 C. 
 
 Cacodyl oxide, 17. 
 
 -test, 17. 
 Calcium acetate, 22. 
 
 alkoxide of dextrose, 37. 
 
 benzoate, 51. 
 
 carbamate, 49. 
 
 carbide, 24. 
 
 citrate, 34. 
 
 oxalate, 28, 29. 
 
 -oxide test, 3. 
 
 potassium ferrocyanide, 44. 
 
 racemate, 33. 
 
 saccharate, 39. 
 
 salicylate, 52, 65. 
 
 tartrate, 33. 
 Camphor, 67. 
 
 Artificial, 67. 
 Camphoric acid, 67. 
 Cane-sugar. See sucrose. 
 Caramel, 39. 
 Carbamate, Calcium, 49. 
 Carbamic acid, 49. 
 Carbide, Calcium, 24. 
 Carbolic acid. See phenol. 
 Carbon, Allotropic modifications of, 
 4, 5. 
 
 Detection of, 1, 2. 
 
 disulphide, 12, 46, 47, 49. 
 
 monoxide, 29. 
 
 tetrachloride, 8. 
 Carbonization, 1. 
 Carbylamine, Ethyl-, 15. 
 
 Methyl-, 12. 
 
 -reaction, 12, 54. 
 Carbylamines, 12, 15. 
 CARIUS'S test, 3, 
 
 Casein, 38, 66. 
 Catechol, 63. 
 Cellulose, 41, 42. 
 
 Nitro-, 41, 42. 
 Charcoal, Bone-, 4, 5. 
 
 Wood-, 4. 
 Chloral, 34. 
 
 hydrate, 34, 35. 
 Chloride, Benzyl, 60. 
 Chlorobenzene, Mono-, 51, 52, 56. 
 Chloroform, 3, 8, 26, 27, 34, 51. 
 Chloropicrin, 62. 
 Cinchona-bark, 66. 
 Cinnamic acid, 61. 
 Citrate, Calcium, 34. 
 Citric acid, 33, 34. 
 Coagulation of proteins, 42, 43. 
 Coal-gas, 1, 24. 
 Coffee-beans, 66. 
 Collodion, 42. 
 
 Colour-base of magenta, 68. 
 Congo-red, 70. 
 Copper acetylene, 24. 
 
 albuminate, 43. 
 
 alkoxide of dextrose, 37. 
 
 ammonium cyanurate, 48. 
 oxalate, 30. 
 
 oxalate, 29, 30. 
 CRAFTS. See FRIEDEL. 
 Cresol, 53. 
 
 CRISMER'S test, 9, 10. 
 Crystallization, 7. 
 Cupric xanthate, 47. 
 Cuprous xanthate, 47. 
 Cyanate, Ammonium, 47. 
 
 Potassium, 45, 47. 
 Cyanic acid, 46. 
 Cyanide, Potassium, 27, 44, 45, 
 
 46, 62. 
 silver, 44. 
 
 Silver, 44. 
 
 Cyanurate, Copper ammonium, 48. 
 Cyanuric acid, 48. 
 
 D. 
 
 Detection of carbon, 1, 2. 
 halogens, 2, 3. 
 hydrogen, 1, 2. 
 nitrogen, 2. 
 sulphur, 3, 4. 
 
78 
 
 INDEX 
 
 Dextrin, 40, 41. 
 Dextrose, 35, 37, 40, 41. 
 Diastase, 40. 
 Diazo-aminobenzene, 56. 
 
 -benzenesulphonic acid, p-, 64. 
 
 -compounds, 56. 
 
 Dibasic acids, Saturated, 28-32. 
 Diethyl-amine hydrochloride, 14. 
 
 -nitrosoamine, 14. 
 
 oxalate, 31. 
 
 Dihydroxy benzenes, 63. 
 Dimethyl-amine, 14, 55. 
 
 aniline, 55. 
 
 oxalate, 30. 
 Dinitro-anisole, 3 : 5-, 61. 
 
 -benzene, w-, 61; o-, 61; p- t 61. 
 
 -a-naphthol, 69. 
 Dioses, 38, 39. 
 Diphenyl-amine, 54, 55. 
 hydrochloride, 55. 
 
 -urea, 65, 56. 
 DIPPEL'S oil, 71. 
 Distillation, Fractional, 5. 
 
 Steam, 6. 
 
 Dithiocarbamate, Ammonium, 49. 
 Dyeing, 62, 65, 69, 73. 
 
 E. 
 
 Egg-albumin, 2, 3, 22, 42, 43. 
 
 Ela'idic transformation, 25. 
 
 Eosin, 30. 
 
 Esters, 10, 11, 18-21. 
 
 Ether, 6, n, 12. 
 
 Ethers, 11, 12. 
 
 Ethoxide, Sodium, 8, 9, 14. 
 
 Ethyl acetate, 20, 21, 42. 
 
 alcohol, 5, 8-10, 11, 18, 20, 21, 
 
 23,26,27,31,42,47,58. 
 Tests for, 27, 58. 
 
 -amine hydrochloride, 13. 
 
 benzoate, 58. 
 
 -carbylamine, 15. 
 
 chloride, 10. 
 
 -mercaptan, 12. 
 
 nitrite, 13. 
 
 -sulphate, Barium, 11. 
 Potassium, 12, 15. 
 
 -sulphuric acid, 10, 11. 
 Ethylene, 23, 24. 
 
 bromide, 24. 
 Extraction with solvents, 6. 
 
 F. 
 
 Fatty acids, Higher, 19. 
 
 Volatile, 19. 
 FEELING'S solution, 33, 35. 38, 39, 
 
 57, 63. 
 Ferric acetate, Aceto-, 18. 
 
 Basic, 18. 
 
 succinate, Basic, 31. 
 thiocyanate, 46^ 49. 
 Ferricyanide, Potassium, 45. 
 Ferrocyanic acid, 44. 
 Ferrocyanide, Potassium, 15, 43, 44, 
 
 45, 57 
 calcium, 44. 
 Fluorescein, 66. 
 Formaldehyde, 22. 
 " Formalin/' 22. 
 Formate, Mercuric, 16. 
 Mercurous, 16. 
 Potassium, 27, 28. 
 Silver, 16. 
 Sodium, 29. 
 
 Formic acid, 15-17, 27, 32, 34. 
 Fractional distillation, 5. 
 FRIEDEL and CRAFTS'S reaction. 
 
 51. 
 
 Furfuraldehyde, 36. 
 -hydrazone, 36. 
 -test, 36. 
 Fusel-oil, 9, 
 
 G. 
 
 Galactose, d-, 38, 39. 
 Gallic acid, 63, 65. 
 Gall-nuts, 66. 
 
 GATTERMANN'S reaction, 56. 
 Gelatin, 66. 
 
 Glucosazone, Phenyl-, 35, 36. 
 Glucose-sulphate, Barium, 37. 
 
 -sulphuric acid, 37. 
 Glycerol, 15, 19, 27, 28, 36, 
 
 72. 
 
 Glycerose, 36. 
 Glyceryl oleate, 25. 
 Glyoxylic acid, 43. 
 Graphite, 4. 
 Gum-benzoin, 57. 
 Guncotton, 42. 
 
INDEX 
 
 79 
 
 H. 
 
 Halogens, Detection of, 2, 3. 
 Heterocyclic compounds, 71, 72. 
 Hexodioses, 38, 39. 
 Hexoses, 36-38. 
 
 Hydrochloric-acid test for, 36, 
 
 37. 
 
 " Humic substances," 37. 
 Hydrazines, 57. 
 Hydrazobenzene, 55. 
 Hydrocarbons, Saturated, 7, 8. 
 
 Unsaturated, 23-25. 
 Hydrocyanic acid, 43, 44. 
 Hydrocyclic compounds, 67. 
 Hydrogen, Detection of, 1, 2. 
 Hydrolysis of nitriles, 15. 
 Hydroxy-acids, 32-34. 
 
 I. 
 
 Indigo, 73. 
 
 -sulphonic acid, 73. 
 
 -vat-dyeing, 73. 
 Indophenin-reaction, 71, 72. 
 Iodide, Benzyl, 60. 
 lodoform, 27, 34. 
 
 -test, 10, 13, 14, 27. 
 Iron ammonium tartrate, 32, 33. 
 Isatin, 72, 73. 
 /sonitriles, 12, 15. 
 /sopurpurate, Potassium, 62. 
 /sopurpuric acid, 62. 
 
 K. 
 
 Keratin, 43. 
 
 Keto-alcohols. See sugars. 
 Ketones, 22, 23. 
 KJELDAHL'S method, 2. 
 KNOP, 48. 
 
 L. 
 
 Laboratory methods, 5-7. 
 Lactic acid, 32. 
 Lactosazone, 39. 
 Lactose, 38, 39. 
 Lsevulic acid, 37. 
 Lsevulose, 38. 
 -test, 38, 39, 
 
 LASSAIGNE'S test for nitrogen, 2, 
 
 27. 
 Lead acetate, 4, 5, 19, 29. 
 
 oleate, 26. 
 
 oxalate, 29. 
 " Lead-plaster," 26. 
 Lemons, 33. 
 
 keuco-base of magenta, 68. 
 LIEBERMANN'S test, 55. 
 LIEBIG, 48. 
 Lignin, Test for, 42. 
 Linseed oil, 46. 
 
 M. 
 
 Magenta, 4, 21, 68. 
 Malt-extract, 40. 
 Martius's yellow, 69. 
 Melting-point, Determination of, 
 
 6. 
 
 Mercaptan, Ethyl-, 12. 
 Mercuric formate, 16. 
 Mercurous formate, 16. 
 Methane, 7, 8, 18. 
 Methyl alcohol, 22, 29. 
 
 -amine, 12, 15. 
 
 -carbylamine, 12. 
 
 -mustard-oil, 13. 
 
 -nitrolate, Sodium, 14. 
 
 -nitrolic acid, 14. 
 Method, KJELDAHL'S, 2. 
 Methods, Laboratory, 5-7. 
 Methoxide, Sodium, 61. 
 Methylene chloride, 8. 
 Milk, 38, 66. 
 MILLON'S reagent, 43. 
 Monobasic unsaturated acids, 25, 
 
 26. 
 
 Monochlorobenzene, 51, 52, 56. 
 Monoses, 35-38. 
 Mucate, Potassium, 38. 
 Mucic acid, 38, 39. 
 Murexide, 49, 50. 
 
 -test, 49, 50. 
 
 Mustard-oil, Methyl-, 13 
 reaction, 12, 13.' 
 
 N. 
 
 Naphthalene, 6, 69. 
 -monosulphonic acids, 69. 
 picrate, 69. 
 
80 
 
 INDEX 
 
 Naphthionate, Sodium, 70. 
 Naphthionic acid, 70. 
 Naphthol, 69. 
 Naphthylamine, a-, 70. 
 
 P-, 70. 
 
 Naphthylamines, Test for, 70. 
 Nicotine, 73, 74. 
 Nitrate, Urea, 47, 48. 
 Nitriles, 15. 
 
 Hydrolysis of, 15. 
 Nitrite, Ethyl, 13. 
 Nitro-aniline, m-, 64. 
 o-, 64. 
 p-, 64. 
 
 -benzene, 50, 51, 53, 55, 72, 73. 
 
 -celluloses, 41, 42. 
 
 -compounds, 14, 15, 50. 
 
 -methane, 14. 
 Sodium, 14. 
 
 -naphthalene, -, 69. 
 
 -phenol, o-, 62. 
 P-, 62. 
 
 -prusside-test, 4. 
 Nitrogen, Detection of, 2. 
 Nitrolic-acid reaction, 14. 
 Nitrosp-amine, Diethyl-, 14. 
 
 -amines, 14. 
 
 -dimethylaniline. 55. 
 hydrochloride, 55. 
 
 -phenoxide. Sodium, 55. 
 Nitrous-acid test, 13. 
 Nitrous acid, Test for, 64. 
 
 O. 
 
 Oil, Almond, 25, 26. 
 
 DIPPEL'S, 71. 
 
 Linseed, 46. 
 
 Turpentine, 67. 
 Oleate, Glyceryl, 25. 
 
 Lead, 26. 
 
 Sodium, 25. 
 Olefines, 23, 24. 
 Oleic acid, 25. 
 Osazones, 35, 36. 
 Oxalate, Ammonium, 29, 30. 
 
 Calcium, 29. 
 
 Copper, 29, 30. 
 ammonium, 30. 
 
 Diethyl, 31. 
 
 Dimethyl, 30. 
 
 Lead, 29. 
 
 Oxalate, Potassium, 28. 
 
 ferric, 30. 
 Sodium, 29. 
 Urea, 47. 
 
 Oxalates, Complex, 30. 
 Oxalic acid, 7, 15, 16, 27, 28-31, 
 
 47, 68. 
 Oxamide, 31. 
 Oxidation, 1, 3, 10, 17, 18, 23. 
 
 P. 
 
 Paper, 42. 
 
 Paraffin-wax, 8. 
 
 Parchment-paper, 41. 
 
 Pentoses, 36. 
 
 Petroleum, 6, 8. 
 
 Phenol, 52, 53, 56, 62, 65, 66, 68. 
 
 Ferric-chloride test for, 52. 
 
 -phthalein, 66, 67. 
 Phenoxide, Sodium, 52. 
 Phenyl-carbylamine, 54. 
 
 -glucosazone, 35, 36. 
 
 -hydrazine, 35, 36, 39, 57, 59. 
 
 hydrochloride. 57. 
 Phenylenediamine. m-, 64. 
 
 P-, 65, 
 Phthalic acid. 66. 
 
 anhydride, 66 
 Picramide, 64. 
 Picrate. Naphthalene, 69. 
 
 Potassium, 62. 
 
 Quinoline, 72. 
 
 Picric acid, 53, 62, 63, 69 ; 71, 72. 
 Pinene hydrochloride, 67. 
 Polyoses, 40-42. 
 Potassium acetate, 38. 
 
 benzote, 59, 60. 
 
 calcium Jerrocyanide, 44. 
 
 cyanate, 45, 47. 
 
 cyanide, 27, 44, 45, 46, 62. 
 
 ethylsulphate, 12, 15. 
 
 ferricyanide, 45. 
 
 ferrocyanide, 15, 43 ; 44, 45, 57. 
 
 formate, 27, 28. 
 
 hydrogen saccharate, 38. 
 tartrate, 32, 33. 
 
 isopurpurate, 62. 
 
 mucate, 38. 
 
 oxalate, 28. 
 
 picrate, 62. 
 
 propionate, 15. 
 
INDEX 
 
 81 
 
 Potassium rosolate, 68. 
 
 salt of alizarin, 70. 
 
 silver cyanide, 44. 
 
 tartrate, 32. 
 
 thiocyanate, 46. 
 
 urate, Di-, 49. 
 
 xanthate, 47. 
 Potato-starch, 41. 
 Propionate, Potassium, 15. 
 Propionic acid, 15. 
 Propionitrile, 15. 
 Proteins, 22, 42, 43, 66. 
 
 Tests for, 43. 
 
 Prussian-blue test, 2, 44, 45. 
 Purpurate, Ammonium, 49. 
 Pyridine, 71. 
 
 Test for, 71. 
 Pyrogallol, 63. 
 Pyrrole-red, 71. 
 
 Q. 
 
 Qualitative analysis of carbon com- 
 pounds, 1-4. 
 Quinhydrone, 64. 
 Quinine, 66, 74. 
 
 hydrochloride, 66, 73. 
 
 sulphate, 73, 74. 
 Quinol, 63, 64. 
 Quinoline, 72. 
 
 dichromate, 73. 
 
 hydrochloride, 72. 
 
 picrate, 72. 
 
 R. 
 
 Racemate, Calcium, 33. 
 
 Racemicacid, 33. 
 
 Reaction, ADAMKIEWICZ'S, 43. 
 
 Biuret-, 43, 48. 
 
 Carbylamine-, 12, 54. 
 
 FRIEDEL and CRAFTS'S, 51. 
 
 GATTERMANN'S, 56. 
 
 Indophenin-, 71, 72. 
 
 Nitrolic-acid, 14. 
 
 SCHIFF'S, 21. 
 
 Xanthoprotein-, f 43 . 
 Reagent, MILLON'S, 43. 
 
 SCHIFF'S, 21. 
 
 SCHWEITZER'S, 41. 
 Reagents, Alkaloid-, 71, 73. 
 Resin, Aldehyde-, 21. 
 
 Resorcinol, 38, 39, 63, 66. 
 RocheUe salt, 37. 
 Rosolate, Potassium, 68. 
 Rosolic acid, 68. 
 Rye-bread, 36. 
 
 S. 
 
 Saccharate, Calcium, 39. 
 
 Potassium hydrogen, 38. 
 " Saccharin," 65. 
 Salicylate, Calcium, 52, 65. 
 Salicylic acid, 6, 65. 
 
 Test for, 65. 
 Salting-out, 42. 
 " Salt of sorrel/' 30. 
 " Sand-sugar." See lactose. 
 Saponification, 18-20, 25. 
 Saturated acids, C n H 2 nO2, 15-20. 
 
 dibasic acids, 28-32. 
 
 hydrocarbons, 7, 8. 
 SCHIFF'S reaction, 21. 
 
 reagent, 21. 
 
 SCHWEITZER'S reagent, 41. 
 Silver acetate, 17. 
 
 acetylene, 24. 
 
 cyanide, 44. 
 
 formate, 16. 
 
 -mirror test, 21, 32, 35, 59. 
 
 potassium cyanide, 44. 
 
 thiocyanate, 46. 
 SKRAUP'S synthesis, 72. 
 Smokeless powder, 42. 
 Soap, 19, 20. 
 Sodium acetate, 7, 17, 18, 56. 
 
 benzenesulphonate, 50, 52, 57. 
 
 ethoxide, 9, 14. 
 
 formate, 29. 
 
 methoxide, 61. 
 
 methylnitrolate, 14. 
 
 naphthionate, 70. 
 
 nitromethane, 14. 
 
 nitrosophenoxide, 55. 
 
 oleate, 25. 
 
 oxalate, 29. 
 
 phenoxide, 52. 
 Solvents, Extraction with, 6. 
 Starch, 40, 41. 
 
 Barium alkoxide of, 40. 
 
 -paste, 40. 
 
82 
 
 INDEX 
 
 Starch. Potato-, 41. 
 
 Test for, 40. 
 Steam distillation, 5, 6. 
 Strychnine, 74. 
 
 nitrate, 74. 
 
 Test for, 74. 
 Succinate, Barium, 31. 
 
 Basic ferric, 31. 
 Succinic acid, 31. 
 Succinimide, 31. 
 Sucrose, 1, 36, 39. 
 Sugar. See sucrose. 
 
 Cane-. See sucrose. 
 Sugars, 35-42. 
 Sulphanilic acid, 64. 
 Sulphur, Detection of, 3, 4. 
 
 T. 
 
 Tannin, 66, 71, 73. 
 
 Test for, 66. 
 " Tartar emetic," 33. 
 Tartaric acid, 32, 33. 
 Tartrate, Calcium, 33. 
 
 Iron ammonium, 32, 33. 
 
 Potassium, 32. 
 
 hydrogen, 32, 33. 
 Test, BEILSTEIN'S, 3. 
 
 Cacodyl-, 17. 
 
 Calcium-oxide, 3. 
 
 CARIUS'S, 3. 
 
 Caustic-alkali, 3, 4. 
 
 CRISMER'S, 9, 10. 
 
 Furfuraldehyde-, 36. 
 
 lodoform-, 10,13,14,27. 
 
 KJELDAHL'S, 2. 
 
 La3vulose-, 38. 
 
 LASSAIGNE'S, 2, 27. 
 
 LIEBERMANN'S, 55. 
 
 Murexide-, 49, 50. 
 
 Mustard-oil, 12, 13. 
 
 Nitroprusside-, 4. 
 
 Nitrous-acid, 13. 
 
 Prussian-blue, 2, 44, 45. 
 
 Silver-mirror, 21, 32, 35, 59. 
 
 WILL and VARRENTRAP'S, 2. 
 
 for acetone, 22. 
 anthraquinone, 70. 
 brucine, 74. 
 
 hexoses, Hydrochloric-acid, 36, 
 37. 
 
 Test for lignin, 42. 
 
 naphthylamines, 70. 
 
 nitrous acid, ra-Phenylenedi- 
 amine, 64. 
 
 phenol, Ferric-chloride. 52. 
 
 primary amines, 12. 
 
 pyridine, 77. 
 
 salicylic acid, 65. 
 
 starch, 40. 
 
 strychnine, 74. 
 
 tannin, 66. 
 
 the double bond, VON BAEY- 
 
 ER'S, 24, 25, 50, 71. 
 Tests for acetic acid, 17, 18, 
 ??. 
 
 aniline, 54. 
 
 antipyrine, 72. 
 
 carbon, 1, 2. 
 
 ethyl alcohol, 10, 27, 58. 
 
 halogens, 2, 3. 
 
 hydrogen, 1, 2. 
 
 nitrogen, 2. 
 
 proteins, 43. 
 
 sulphur, 3, 4, 
 
 water in alcohol, 9, 10. 
 Tetramethylalloxantine, 50. 
 Thiocyanate, Ammonium, 3, 49. 
 Ferric, 46, 49. 
 Potassium, 46. 
 Silver, 46. 
 Thiophen, 72. 
 Toluene, 51, 60. 
 Transformation, Elaidic, 25. 
 Tribromo-aniline, 54. 
 -phenol, 52. 
 -resorcinol, 63. 
 Trimethylamine, 14. 
 Trinitrobenzene, 1:3:5-, 61. 
 Triphenylmethane, 51. 
 Trithiocarbonate, Barium, 47. 
 Turpentine, Oil of, 67. 
 
 U. 
 
 Unsaturated acids, Monobasic, 25, 
 26. 
 
 hydrocarbons, 23-25. 
 Urate, Ammonium, 49. 
 
 Di-potassium, 49. 
 Urea, 6, 47, 48, 55. 
 
 nitrate, 47, 48. 
 
 oxalate, 47. 
 
INDEX 
 
 83 
 
 Uric acid, 49. 
 Urine, 37, 47, 48. 
 Estimation of urea in, 48. 
 
 V. 
 
 VARRENTRAP'S method, WILL and, 
 2. 
 
 W. 
 Wax, Paraffin-, 8. 
 
 WILL and VARRENTRAP'S method, 
 
 2. 
 
 Wine, 9. 
 
 WOHLER'S synthesis of urea, 47. 
 Wood, 28. 
 -charcoal, 4. 
 
 X. 
 
 Xanthate, Cupric, 47. 
 
 Cuprous, 47. 
 
 Potassium, 47. 
 Xanthoprote'in-reaction, 43. 
 
C ! 
 
 c /- 1 
 
"-