ANALYTICAL CHEMISTRY BASED ON THE TEXT OF F. P. TBEADWELL REVISED AND ENLARGED BY WiLLIAM T. HALL Volume I. Qualitative Analysis. Ninth English Edi tion. 630 pages. 6X9. 18 figures. Cloth. Volume II. Qitantitative Analysis. Ninth English Edition. 806 pages. 6 X 9. 121 figures. Cloth. LABORATORY METHODS OF INORGANIC CHEMISTRY BY H. AND W. BlLTZ TRANSLATED BY W. T. HALL AND A. A. BLANCHARD Second Edition. 261 pages. 6 X 9. 27 figures. Qoth. TEXTBOOK OF QUANTITATIVE ANALYSIS BT WILLIAM T. HALL Third Edition. 364 pages. 6 X 9. 51 figures. Qoth. OUTLINES OP ORGANIC CHEMISTRY " BY THE LATE F. J. MOORE REVISED BY WILLIAM T. HALL Fourth Edition. 338 pages. 5H X 8J^. Cloth. Analytical Chemistiy BASED ON THE GEBMAN TEXT OP F. P. TREADWELL, Late Professor of Analytical Chemistry at the Polytechnic Institute of Zurich TEANSLATED AND BEVISED BT WILLIAM T. HALL, S.B., Professor Emeritus of Analytical Chemistry at the Massachusetts Institute of Technology VOLUME I QUALITATIVE ANALYSIS NINTH ENGLISH EDITION 5©^ h^ NEW YORK JOHN WILEY & SONS, INC. LONDON: CHAPMAN & HALL, LIMITED \h^^ IN THE REPRINTING OF THIS BOOK, THE RECOM MENDATIONS OF THE WAR PRODUCTION. BOARD HAVE BEEN OBSERVED FOR THE CONSERVATION OF PAPER AND OTHER IMPORTANT WAR MATERIALS. THE CON TENT REMAINS COMPLETE AND UNABRIDGED. Copyright, 1903, 1906, 1913, 1916, 1921, 1930, 1932, 1937 BT WILLLiM T. HALL 1903 Copyright renewed 1931 Copyrighted Canada, 1932, 1937. International Copyright, 1932, 1937 WILLIAM T. HALL, Proprietor PRINTED IN THE UNITED STATES OP AMERICA 9/43 PREFACE TO THE NINTH EDITION Many changes have been made in this revision. Part I, which deals with the principles upon which analytical chemistry is based, has been largely rewritten to make it correspond more closely to modem chemical theory. Part II, which treats of the reactions of cations, has been rearranged so that the order of treatment may correspond to the sequence in which the laboratory tests are made. In previous editions, the reactions of the alkali cations were discussed first and the cations of the silver group, which constitute Group I of the analytical pro cedure, were considered last. Since this has caused some confusion in the minds of beginners, it is believed that the new arrangement will be found more convenient. Considerable new material has been introduced throughout the book. The description of properties of the elements has been amplified and many new tests describe with special attention to drop reactions. A procedure for semi-microchemical analysis has been introduced. Since it was th* earnest desire of the publishers not to increase the price of the book, tbe liitroduction of the new material made it necessary to discard considerably portions of the former text. Thus, for the analysis of each ^ up o^^afQons, a single scheme of analysis is now recom mended which will, it is hoped, make it easier for the beginner. The excellent scheme of Noyes and Bray for the analysis of the rare and common metals has been omitted with regret. The procedure is so long that few students find time to follow it throughout and it has been found better to refer them to the original text of Noyes and Bray where greater attention is paid to the necessary details of manipulation and considerable information is given about tests that were made in de veloping the scheme. In some cases, as in the analysis of the platinum metals and in the tests for the earths and earth acids, the scheme of Noyes and Bray no longer corresponds to the best modem practice. The section on spectroscopy has also been shortened with regret. The technique of spectroscopic analysis has developed so remarkably during recent years that it is now beyond the scope of this book to give adequate treatment to this important method of analysis. The syllabus of the course in qualitative analysis given at the Massachusetts In stitute of Technology has also been omitted, partly to save space and iv PKEFACB TO THE NINTH EDITION partly because of changes made from year to year in the actual method of instruction. Tke labor of proofreading has been lightened very considerably by • conscientious work on the part of my associates Professor Stephen G. Simpson and Mr. Robert M. Sherman, Jr., who have offered many valuable suggestions. "WILLIAM T. HALL MASSACHUSETTS INSTETDTB or TECHNOLoar April, 1937 ' CONTENTS PART I GENERAL PRINCIPLES PAQB International Atomic Weights, 1937 Back Caver Qualitative and Quantitative Analysis 1 Reactions in the Wet Way 1 Law of Mass Action 2 Theory of Electrolytic Dissociation or Ionization 4 Ionization Values of Common Electrolytes 11 Nomenclature of the Ions , 12 Mass-Action Law in Terms qf Activities 12 Activity Coefficients .* 13 Equilibrium between a Solid and Two Liquids 14 Ionization Constants of Weak Acids 16 Ionization Constants of Weak Bases j 17 Ionization of Water. The Hydrogen Exponent 17 Solubility Product 19 Complex Ions 27 Reactions of the Ions 29 Oxidation and Reduction 30 Electromotive Series and Electrode Potentials 39 Normal Potentials 43 Oxidation Potentials 46 The Effect of a Common Ion 49 Hydrolysis 52 Amphoteric Electrolytes 58 Detection of Acids and Bases. Theory of Indicators 61 Colloidal Solutions 64 Evaporation of Acids 68 Filtration and Washing of Precipitates 70 Reactions in the Dry Way 71 Spectrum Analysis 79 Division of the Metals into Groups , 85 Periodic Table 87 Concentrations of Reagents 88 Reactions of the Elements 93 Abbreviations of Chemical Abstracts 93 v VI CONTENTS PART II REACTIONS OF THE METALS (CATIONS) GROUP I PAQB SilTOr ? 99 Mercury (Mercuious Salts) ; 104 Lea,d 110 Analysis of Group 1 115 • GROUP II Mercury (Mercuric Salts) 118 Lead \: ! '. 123 Bismutk ; 123 Copper - 128 Ca-dmium •; 138 Arsenic 141 Antimony '. / .' 159 Tin / 166 Aaa.l3-sis of Group II.... .• 178 GROUP III Aluminum 188 Ckromiom ; ; 195 Iron ; 205 Manganese 218 Nickel 230 Cobalt .• 238 Zinc ' 245 Separation of Group HE from Groups IV and V. , 250 Analysis of Group III 251 . GEOU"P IV (ALKALINE EABTHS) General Characteristic Reactions i. _ 259 Calcium 259 StroatiuEi .,,....,... 264 Barium ., 266 Magnesium ,; -. 270 Separation of the Metals of Group IV.... ' 275 GROUP V (ALKALIES) Potassium ^.-r. 280 Sodium :...." 284 Ammonium 289 Separa-tion ot the Metals ot Group V 295 CONTENTS vii PART III REACTIONS OF THE ACID CONSTITUENTS (ANIONS) ^^^^ Division of the Acids into Groups 297 GROUP I Hydrochloric Acid .'. 299 Chlorine 305 Hypochlorous Acid 306 Hydrobromic Acid 310 Bromine 313 Hydriodic Acid 315 Iodine 319 Detection of HCl, HBr, and HI in the Presence of One Another 320 Detection of Halogen in the Presence of Cyanide 323 Hydrocyanic Acid 324 Cyanogen 331 Detection of Nitrogen in Organic Substances 331 Detection of HCN in Presence of HCl, HBr, HI,H4Fe(CN)6], H3[Fe(CN)6] and HCNS. 332 Ferrocyanic Acid 333 Ferricyanic Acid 336 Thiocyanic Acid ,, 339 Detection of HCNS in Presence of Halogen and Cyanide , 341 Detection of HCNS, H4[Fe(CN)6] and HsIFeCCN)^ 343 Cobalticyanic Acid 344 GEOUP II Nitrous Acid 345 Hydrogen Sulfide (Hydrosulfuric Acid) 350 Sulfur 355 Acetic Acid 357 Cyanic Acid 360 Hypophosphorous Acid 362 Hydrazoic Acid 364 GROUP III Sulfurous Acid 365 Carbonic Acid. . . .- .' 370 Percarbonic Acid 374 Boric Acid 375 Perboric Acid.' 378 Oxalic Acid 379 Tartaric Acid 382 Citric Acid 387 Phosphorous Acid 390 viil CONTENTS -e PAQE] Metaphosptorio Acid » • 393 PjTDphosphoric Acid • 395 Iodic Acid 396 GRODE IV Phosphoric Acid 399 Hypopliosphoric Acid 405 Phosphorus 406 Arsenious Add 142 Arsenic Acid 147 Chromic Acid ; 199 Thiosulfuric Acid '••• 411 ' Detection of Sulfurous aad Tfi'iosulfuric Acids in the Presence of Hydrogen Sulfide. " 414 GBO:TP V Nitrie Add 416 Detection of Nitric Acid in tie Presence of Nitrous Acid 420 Chloric Acid 422 Detection of HydrocUoric, Nitric, and Chlorie^Aeids in the Presence of One Another 424 Perchloric Acid 426 Persulfuric Acid 428 Monopepsulfuric Acid (Care's Acid) 431 GEOTTP VE Sulfuric Aeid 432 Hydrofluoric Acid 435 Fluosilicie Aeid : 441 GaoOT VII Silicic Add 443 Treatmenl; of Jnsoluble Silicates .".... 446 Silicon 450 PART rv SYSTEMATIC ANALYSIS , Analysis of Solid and Non-melallie Substances.,. • •. • 453 Preliniinsiiy Examination ^ 453 Dissol-ving thft Substance 460 Solubility Ta.We , '• 462 Methods of Getting Insoluble Substances into Solution._ .^.-^. 467 Examination for the Mstals (Ca,tions) 471 Examination for the Acid Constituents (Anions), Method of Treadwell 474 Examination for Acid Constitueats, Method of A. A. Noyes 479 CONTENTS IX PAGE Analysis of Alloys 489 Analysis of a Liqiiid 489 Analysis of a Gas 490 SUPPLEMENT Semi-micro Analysis ~ 493 Cation Analysis 494 Anion Analysis • • • 501 PART V REACTIONS OF SOME OF THE RARER METALS GBOUP II Molybdenum 506 SftVKCiVQHi 508. Tellurium 511 Germanium 514 Gold 615 Platinum 621 Palladium 524 Rhodium 527 Osmium , 630 Ruthenium •.' 532 Iridium , •. • 533 Separation and Detection of the Six Platinum Metals 636 GROUP III Beryllium or Glucinum 540 Uranium 542 Titanium 546 Zirconium 552 Thorium 556 Hafnium. 559 The Rare Earth Metals 560 Scandium 562 Yttrium 563 Europium 566 Gadolinium • 566 Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium, Lutecium 566 Cerium 566 Lanthanum 571 Neodymium and Praseodymium 572 Samarium 573 Thallium 573 Indium 576 Gallium 578 Vanadium 579