NEW BOOKS elusion of some "descriptive chemistry" in which various types of reactions are observed. Experiments involving acidbase equilibria and solubility equilibria illustrate important applications of equilibrium principles. In institutions having a large enroll ment in freshman chemistry laboratory, some of the work would have to be done as group experiments or as dem onstration by the instructor, because of equipment limitations. (This fact is recognized by the auihors.) On the other hand, some important physicochemical measurements are made with very simple apparatus; for example, heats of reaction are determined in a calorimeter consisting of a polystyrene cup and cover placed in a beaker. It seems to this reviewer that Exp. 7, Atomic Spectra, is mon; properly in the area of physics than in chemistry. Al though it is desirable for students plan ning to major in chemistry to get ac quainted with reference sources early, it is doubtful if Exp. 5, Library Refer ences, should be required of all students in the freshman course, and large classes would seriously tax the chemis try library facilities. Each experiment includes a brief in troduction outlining the principle to be studied, and the experimental approach to be used. Strong features of the book are that graphical representation of data is used frequently, and each exper iment is followed by questions and problems, related to the experiment, which are to be answered in the written report. The manual includes several "Student Research Projects ' which might be more appropriately called simply "Optional Experiments," since com plete procedural directions are given. It is unfortunate that the authors did not use the IUPAC convention of elec trochemical potentials. The "Four Place Logarithms" table would be more useful if proportional parts were given; however, (he tabular mantissas are ade quate for many of the calculations, which involve weights tiiken on a triple beam balance and/or titration volumes taken to 0.1 ml. Relatively few errors were noted. On p. 29, the formula of hydrazine should read N H 2 N H , ; on p. 122, the Kx„ of KC10 4 , given as 8.9 Χ 10"13, is obviously wrong. This reviewer sees no reason for the hydronium ion to be written H:( + 0, rather than the usual H:iO + . Use of the term "electric bal ance" for a single-pan, constant-sensi tivity balance of the type described (pp. 11, 12) implies an erroneous prin ciple of operation. On the whole the book is well writ ten. Satisfactory performance of the experiments and completion of the
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Circle No. 197 on Readers' Service Card VOL. 39, NO. 4, APRIL 1967
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