BIBLIOGRAPHY

A. EUCKEN, Grundriss der physikalischen Chemie, 4 Aufl., Lpz., Akad. Verlag, 1934, XXIII, 699, 179, Abb., Mk. 27.*

A. EUCKEN. Fundamentals of Physical Chemistry.

The Russian reader is familiar with Eucken from the third edition of Chemical Physics. The second and third parts appeared in Russian translation from that edition. The first part is available in translation from the second German edition.

The new Eucken differs substantially from the previous one. The author has again returned from chemical physics to physical chemistry. Apparently, two reasons played a role here. The third edition was too large in volume. Eucken has now reduced it by one third (667 pages of text, instead of 1002).

In addition to abridgements, the author has partly moved toward simplification in order to bring the book closer to the character of a textbook. The diversity of the material has narrowed somewhat; the course has become more compact and concentrated.

It would be erroneous to think that the new edition is simply abridged in comparison with the third. It is not only a matter of cuts. Work on the new edition required more than scissors. The material is distributed differently, some conclusions have been changed, and, finally, in places there is new material in comparison with the course of chemical physics. The nature of the exposition and the arrangement of the chapters have become so unstable in physical chemistry that one and the same author arranges the contents of the book differently in two editions.

A good course in physical chemistry should teach the reader to use its methods for solving the corresponding problems. The book should emphasize both the thermodynamic and the statistical-mechanical method. Here are two ways of considering any physicochemical problem. Depending on the nature of the problem, in each case one or the other method proves more suitable. No one, in order to find an approximate value of the equilibrium constant as a function of temperature, will use statistical mechanics, for in this case thermodynamics gives the answer more quickly, more easily, and more simply. It is important that the reader, having mastered both methods, apply them correctly.

The merit of Eucken’s third edition was that throughout the book both methods were developed in parallel. Questions are considered both thermodynamically and kinetically. This is valuable, for in this way the formal infallibility of the thermodynamic method is supplemented, becomes more evident and perceptible when illuminated from the molecular-kinetic point of view. Many examples of this can be given. Let us point to osmotic pressure, to heat capacity, etc. But a mere indication of the methods is not enough. The principles of atomic mechanics must be given, for only then does the nature of chemical forces, the problem of activation, bond energy, etc., become understandable.

Just as it is impossible to throw classical mechanics out of nineteenth-century science and get by without it, so now, from a book devoted to physical chemistry, it is impossible to throw out questions of atomic mechanics. Unfortunately, this is not clear to everyone. No one will assert that one need not know that kinetic energy is equal to half the product of mass and the square of velocity. But there are still, unfortunately, many teachers who doubt whether the chemist needs to be told about quanta, about the structure of the atom in a course of physical chemistry. Without the principles of atomic mechanics it is impossible to do in presenting the contemporary state of science.

When Eucken was preparing the third edition of his book, he was imbued with this awareness. He devoted approximately one third of the text to questions of the structure of matter. As a result there appeared a good book, but, unfortunately, too cumbersome and in places too difficult—a book not for the student, but for the graduate student.

* Based on materials of the Critical-Bibliographical Scientific Research Institute of the People’s Commissariat of Heavy Industry.

Preparing the fourth edition of the book, Eucken apparently set himself the task of expanding his readership and bringing the course closer to chemists. The book can be used as a textbook for university students when it has already served for several class hours. As for higher educational institutions, even the abridged Eucken will hardly suit them. We get the impression that the fourth edition has moved away from chemical physics, but has not arrived at a university textbook.

The course of physical chemistry is divided into seven chapters. The first sets forth the equation of state, elements of kinetic theory, the basic equation of this theory (by the way, partly meeting the inaccurate traditional method, when speeds are confused with the components of velocities and when the reader does not understand from the derivation how the mean square of the speed appeared there), the doctrine of aggregate states, solutions and osmotic pressure. The second chapter is devoted to the first principle of thermodynamics, some thermodynamic effects, the statistical theory of heat capacity, and so on.

It seems to us that the material of the first two chapters could have been presented more concisely. We do not see the sharp boundary that compels Eucken to separate the caloric and thermal equations of state. In this respect we are inclined to give preference to the third edition. There, after an exposition of the general foundations of thermodynamics and statistics (the first 94 pages), individual bodies and mixtures follow. This enables the author to operate freely with the necessary concepts and to present the subject in all detail, referring to the first part.

In the next chapter the discussion concerns the thermodynamics of chemical equilibrium. Here are the law of mass action, equilibria in solutions of electrolytes, heterogeneous equilibrium, the phase rule, and the calculation of equilibria from thermochemical data. A novelty here is the introduction of an approximate calculation according to Ulich. We note this because one can see here the first step toward the tabulation of thermodynamic data. The American method, as is known, did not take hold in Germany. At the end of this same chapter, calculations are given by the statistical method of equilibrium. Boltzmann’s law and Maxwell’s distribution law have found their way here.

In the third edition the statistical method was given in the first chapter. That was better, since it allowed the author in the subsequent exposition to use the fundamental Boltzmann law.

In the fourth chapter a time factor is introduced into physical chemistry. The exposition begins with diffusion phenomena, after which the question of the rate of formation of a new phase is considered and, finally, chemical kinetics is given. The latter, apart from minor changes (the introduction of a paragraph on the propagation of rapidly proceeding reactions, small abridgments in other places), has remained the same as in the third edition.

The fifth chapter is completely new. It is chiefly devoted to classical optics. The reader will find here the theory of polarization of light, refraction, absorption, rotation of the plane of polarization, and so forth. The Raman effect and interference experiments for determining the structure of crystals by the method of X-rays also belong here.

Three paragraphs are devoted to the electromagnetic theory of light and Maxwell’s equations. In general, this is a small chapter with purely physical content. Eucken needs it as a framework for the X-ray structure and the Raman effect.

In the sixth chapter we find the application of the classical theory of electricity to structural questions. It begins with Faraday’s laws, elements of electronics, ionization, and classification of compounds by polarity. Next is given what chemistry can extract from Coulomb’s law. Here are Kossel’s theory, lattice energy, the structure of polar crystals, dielectric polarization, the connection with refraction, the polarizability of ions, electrostatic calculation of the chemical bond, and dipole moments. The list of questions set forth is very successful.

After this the foundations of Debye’s theory of strong electrolytes are set forth. Electromotive forces are included in the same chapter. Here it is appropriate

Bibliography

It should be noted that the translation of the second part of the third edition of Eucken, supplemented and revised by A. N. Frumkin, is better than the original. The electromotive forces, potentials, and adsorption may be recommended as presented by A. I. Frumkin.

The last chapter is devoted to the laws of quantum mechanics. This part has been shortened in comparison with the third edition. It begins with the Franck and Hertz experiments, followed by the law of equivalence.

Very little space is devoted to photochemistry. A considerable part of the chapter is devoted to spectra. On the last 19 pages of the book, wave mechanics has found a place. This is far too little to give a correct understanding and the possibility of assessing the significance of the methods of the new mechanics for questions of the chemical bond, etc.

For reasons of economy of space, the chapter on radioactivity has been entirely omitted; it has fallen outside the author’s field of view.

As a new feature it should be noted that almost every chapter ends with problems and examples for practice.

Under our conditions, the new, partially abridged Eucken as a textbook for higher educational institutions is scarcely suitable. Since Eucken serves us, graduate students and scientific workers, we believe that a course of chemical physics better meets its purpose.

I would like to draw attention to one further circumstance. Eucken is very reluctant to cite non-German authors. Nothing, for example, is written about Parachor, and the name of Sugden is not mentioned. The English and others likewise do not lag behind. In one quite good textbook of physical chemistry Nernst is not mentioned in the exposition of the third law of thermodynamics. It is very sad that many foreign books are marked by the stamp of national partiality to the detriment of scientific objectivity.

Ya. K. Syrkin

J. HENGSTENBERG u. KARL WOLF, Elektronenstrahlen und ihre Wechselwirkung mit Materie, Lpz., Akad. Verlagsges., 1935, 236, 12, 182 Abb. (Hand- u. Jahrbuch der chemischen Physik, Hrsg. von A. Eucken u. K. L. Wolf. Db. 6 Abschnitt. I A. Mk. 24).

J. HENGSTENBERG and KARL WOLF, Electron Beams and Their Interaction with Matter.

Within a short span of time, entirely new methods of investigating matter have undergone powerful development—methods that have already penetrated even factory practice. Among the new methods, the study of the structure of matter by means of electron beams occupies a special place, successfully competing with the long-established method of X-ray analysis. In connection with this, the need arose to set forth the modern doctrine of electron beams and their interaction with matter in a form accessible not only to a narrow circle of specialist physicists, but also to workers directly studying the structure of matter, primarily chemists.

The book under review belongs to a series of books intended to set forth new methods used in chemical physics. The authors have sought to give as complete a description as possible of the theoretical foundations of the new methodology, as well as of its numerous practical applications. Taking into account that the future reader is a chemist of education and has previously had little contact with this branch of physics, the authors from the very beginning give a survey of the classical and new theories of electron beams, starting with Lenard’s first work on cathode rays and ending with an exposition of Dirac’s theory of the electron. Despite its great concision and brevity (34 pages), the survey is at the proper scientific level and is very useful.

Then follows a review of the experimental methods for obtaining electron beams; the survey is supplied with a large number of useful practical indications.

The part devoted to the theory of the interaction of electron beams with matter is less successful. This is explained by the fact that such a complex question