ELECTROANALYTICAL CHEMISTRY AND INTERFACIAL ELECTROCHEMISTRY 155 Elsevier Sequoia S.A., Lausanne - Printed in The Netherlands

B O O K R E V I E W S

Chemisches Fachrechnen, by Helmut Seidler, Umschau Verlag, Frankfurt am Main, 1968, 178 pages, DM 15.80.

This is the ninth and latest paperback in the series Chemie far Labor und Betrieb edited by Reinhold Ellmer. The seventeen sections provide a concise introduc- tion to some simpler, basic types of chemical calculation with the emphasis upon problems of immediate practical significance. The treatment is in keeping with the view, expressed by the author in his preface, that "Ein gut ausgearbeitetes Beispiel sagt viel mehr als zu breit ausgelegte theoretische Erl/iuterungen."

The author provides brief theoretical introductions to some topics, states and underlines where appropriate the important principles and describes the essential practical details of one or two key experiments. However, his book primarily consists of about 100 worked examples and 382 graded problems for the student to tackle. Numerical answers to the problems, and sometimes the essential workings, are given at the end of the book. The appendix also lists relevant symbols and abbreviations, solubility product values and four-figure atomic and formula weights. There is as well a loose-leaf card of four-figure logarithms. The detailed contents pages adequate- ly serve as an index.

The fifteen pages comprising sections 1, 2, 3 and 7 deal briefly with exponents, logarithms, the slide rule and logarithms of reciprocals as aids to computation. After sections 4, on density, and 5, on the mole, section 6 explains the expressing of con- centration in weight per cent, volume per cent, grams per litre, molarity and mole per cent. The stoichiometric calculations in section 8 include examples from simple gravimetric analysis and percentage yield in organic preparations. Section 9, which deals with equivalent and normality, is followed by four sections on volumetric analysis involving acids and bases, potassium permanganate, iodine and bromine. Section 14 on gases includes molecular weight determinations by Victor Meyer and Dumas, pressure-temperature corrections. Dalton's partial pressure law and the collection of gases over volatile liquids. Under the heading of elementary organic analysis, section 15 explains the calculation of empirical and molecular formulae from gravimetric data. The electrochemistry of section 16 comprises calculations on Faraday's laws. The final and ldngest section of the book applies the law of chemical equilibrium to aqueous solutions. It covers pH, dissociation constants and degree of dissociation of acids and bases, hydrolysis of salts and buffer solutions, solubility and solubility product, common ion effect and the formation of precipitates and complexes.

This compact little book is attractively bound and clearly printed. Teachers should find it a convenient source of chemical problems. Students should find it useful for self-study, and British Students might care to use it as an introduction both to G.C.E. Advanced Level calculations and to their scientific German.

Michael C. Cox, Cheltenham

J. ElectroanaL Chem., 25 (1970) 155