S. PLETENEV and S. SKLYARENKO, Collection of Examples and Problems in Physical Chemistry, Goskhimtekhizdat, Moscow—Leningrad, 1933, pp. 328; price 4 rubles 40 kopecks, bound 60 kopecks, 7,000 copies.

Anyone who has had occasion to teach physical chemistry knows well what an important role, in mastering the theoretical material, is played by the solution of problems and examples. Undoubtedly, a properly chosen and formulated problem can greatly facilitate a student’s understanding of the most difficult sections of this discipline; moreover, through systematic practice in solving numerical examples, one acquires the skill necessary for subsequent research work, not only for a physical chemist but also for a chemist of any specialty. For this reason, problem books in physical chemistry must be counted among the most important teaching aids.

The collection under review contains more than 600 problems and examples; it is therefore the most complete problem book in physical chemistry of all those that have appeared in Russian. The authors, in compiling the book, drew upon problems scattered through a number of physical-chemistry courses, used the most valuable foreign problem books, and introduced a number of original problems.

The collection will undoubtedly be of considerable interest and will be widely used in our higher educational and technical institutions.

While paying tribute to the great amount of work done by its compilers, one must nevertheless note one very substantial shortcoming, one that is, incidentally, characteristic of the overwhelming majority of all similar problem books. Namely, in its content it covers only so-called “classical” physical chemistry, and by no means all sections of the latter are represented with sufficient completeness. Indeed, although the book contains 50 problems on the Clapeyron equation, such sections as Hess’s law, gas dissociation, osmotic pressure, cryoscopy, electrical conductivity of solutions, etc., receive only 20–30 problems each; problems dealing with real gases (the van der Waals equation), the most important properties of the liquid state of aggregation (surface tension, critical phenomena), the solid state of aggregation (with the exception of sublimation of solids), etc., are absent. At the same time, while considerable attention is devoted to thermodynamic relations, molecular-kinetic concepts are scarcely touched upon.

Only three problems are devoted to the kinetic theory of gases; in the remaining sections the molecular-kinetic theory is treated extremely little. A characteristic example is provided by the chapters devoted to chemical kinetics (pp. 166 ff.). Here there is a large number (more than 60) of problems on formal kinetics, the determination of reaction order, etc., but chain reactions do not appear at all, nor do problems on catalysis, although the present significance of these questions is obvious. There are only two problems on activation energy, and in the theoretical introduction the meaning and significance of this concept are explained quite inadequately (p. 202). There is no need even to mention problems on the modern theory of the structure of matter (atoms, solids, etc.): they are entirely absent, although it is unquestionably possible and necessary to select examples of this type. Likewise, there are no problems on adsorption and photochemistry; problems on solutions cover only the classical theory; there are no examples on the calculation of activity, ionic strength, and problems on the modern theory of electrolytes (it should be noted as a merit that in the theoretical introduction to the chapters concerning electrolytes the conventional character of the concept of “dissociation” of strong electrolytes is emphasized).

The second shortcoming of the book is the excessive brevity of the theoretical introductions. Although one must agree with the authors that these introductions should in no way replace textbooks, still, in a number of places they should have been expanded. Thus, for example, the book lacks a formulation of the second law of thermodynamics, although this formulation is given by Carno (p. 51). On p. 37 a formulation of Hess’s law is given, but there are no consequences from it (concerning heats of combustion and formation), although they prove very useful in solving many thermochemical problems. It has already been noted above that in the chapters on kinetics its molecular-kinetic aspect is treated extremely insufficiently.

The formulation of some problems is insufficiently clear. As an example one may cite problem No. 18 (p. 19), in which the “length of the vacuum” is mentioned and it is not specified, as a condition, that the mercury level in the open limb of the barometer remains constant. A similar example is problem No. 20 (p. 187), in which the order of the reaction between formaldehyde and hydrogen peroxide is not indicated. Problem No. 11 (p. 240) is unsuccessful, since in a mixture of benzene with methyl alcohol the latter cannot be regarded as a nonvolatile component.

Among the unquestionable merits of the problem book should be included the large number of detailed worked examples, which are typical for solving the remaining problems, and also the fact that many problems are taken directly from experimental research works. Finally, the introduction into the book of a chapter devoted to problems on the use of reference books should be especially welcomed. Usually far too little attention is paid to this.

In general, despite the noted shortcomings, Pletev and Sklyarenko’s problem book is a valuable teaching aid for higher (and in part for secondary) educational institutions and deserves wide dissemination.

V. Pleskov