ChemThermo: A statistical approach to classical chemical

Introduction to computer programming for chemists (Isenhour, Thomas; Jurs, Peter C.) Journal of Chemical ... Published online 1 May 1973. Published in...
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book reviews problems are quite pedestrian, others are quite interesting: plausable empirical formulas from elemental analysis, platting graphs with the line printer, titration curves, inorganic qualitative analysis scheme, mass spectrometry, and even arganic synthesis, to name a few. Part 3 includes very useful appendices on such topics as binary arithmetic, job processing, computer terminology, program optirni7ation, trouble-shuotlnc, and a hlhliogrephv which icquitecumplere. 'l'hc hook aora an exrrllent tuh in ac. complishing its stated object&es. In a larger context, however, it has several drawbacks. Unfortunately, much of the introductory discussion tends to be oriented far large IBM computers. The book is also apparently committed to hatch job processing which is increasingly inefficient, as time-sharing systems with remote teletype terminals are becoming more popular. A simplified language such as BASIC has. much more appeal for the latter and is much easier to learn. While FORTRAN IV, no doubt, will continue t o be important as a scientific programming language for specialists, BASIC has a wider appeal to all chemistry students, not just majors. The hook will thus disappoint devotees of CAI (computer assisted instruction). It also departs from the typical text in that problem assignments are not given; the examples themselves do not suggest extensions or modifications which the student might attempt to program. However, this book will surely prove useful for teaching FORTRAN t o chemistry students and should be considered by anyone teaching such a course. Stanley E. Anderson Pahiavi Universily Shiraz, Iran

ChemThermo: A Statistical Approach to Classical Chemical Thermodynamics Leonard K. Nash, Harvard University. Addison-Wesley Publishing Co., Reading, Mass., 1971. xii 207 pp. Figs. and tables. 23 X 15 em. $3.50.

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Leonard Nash has once mare advanced the teaching of chemical science by developing "advanced but fundamental concepts in a form accessible t o the first-year student. "ChemThermo" approaches thermodynamics through elementary statistical ideas; in a logical order, and with the same articulate clarity that characterized Nash's earlier hooks. I find the first three chapters, which develop the laws of thermodynamics, particularly appealing; the approach is extremely similar t o the one that has evolved in my own teaching of thermadynamies to first-year people. The notions of microstate and macrostate, o f ' the overwhelming probabilities associated with most probable configurations for many-particle systems, and the relationship of these ideas to irreversibility have a natural appeal that gives vitality to thermodynamics. In my experience, only the most educated and wisest of first-year stuA308 /Journal of Chemical Education

dents penetrate an abstract phenomenological approach t o thermodynamics beyond the level of manipulating symbols, and retain any physical sense of heat, enthalpy, entropy and free energy. On the other hand, when these concepts are tied to the behavior of individual particles through simple statistical ideas, they become meaningful and useful to most students. The fourth and final chapter of the hook develops the consequence of the First and Second Laws, treating free energies, phase equilibria, colligative properties and chemical equilibrium. The material in this chapter is, almost necessarily, more nearly standard than the content of the first three chapters. However the emphasis on the relationship between observables and mathematical statements is particularly well done, and the many examples here, like those in the earlier chapters, illustrate the physical concepts and the magnitudes of variables very effectively. There are seventy problems of the challenging sort one expects from Leonard Nash, and a brief discussion of elementary operations of calculus. With these appendices, the hook is self-contained, excellent for the bright student who wants to study a subject independently, as well as for use in a course. All in all, I consider this book a valuable contribution to chemical pedagogy. R. Stephen Berry University of Chicago Chicago, Illinois 60637

Fast Reactions David N. Hague, University of Kent. Wiley-Interscience, New York, 1971. viii + 159 pp. Figs. and tables. 23.5 X 15.5 cm. $8.50. Although most texts beyond the firstyear college level (and even same of those) include a section on fast reactions, no monograph aimed for upper level undergraduates and graduates has been available prior to the appearance of this volume. Despite the many goad qualities of this book, its lack of depth makes i t fall short of its target. "Fast Reactions" consists of two parts. In the first section are an introductory chapter and a chapter an experimental methods. The latter comprises almost onehalf the entire volume. Two chapters an results plus appendices make up the remainder. The chapter on experimental methods covers perturbation techniques and competition methods. The main purpose should be accomplished in this chapter; yet i t represents the weakest element of the book. The principles of chemical relaxation are presented from the standpoint of transient perturbation methods such as temperature- or pressure-jump applied to single-step reactions. Stationary methods receive a brief, qualitative mention. The treatment does not rise above the level of elementary algebra and the first-order differential equation of chemical kinetics. Thus, only one example of a multi-step reaction is given, and it, too, is treated similarly.

Herein lies the basis for the book's inutility. The elementary approach to the theory of chemical relaxation is inadequate far the graduate student, and inherently lacking in interest or challenge for both graduate and undergraduate, alike. Furthermore, it is misleadine. ... as i t imdies a l a h g on the part ot t l ~ cnwlhud tu rope ulth uumpler ryitems. wl~ich,in fact, rr ra particularly ueli-suited to handle m comparison with other kinetic methods. One example will illustrate the shortcomings of this approach. The relaxation times for the scheme A + B t AB I Care sought. Step A + B t AB equilibrates much more rapidly than the second step, and can be treated independently. Hence, the problem is to find the longer of the two relaxation times. However, this system possesses three independent concentration variables, with but a single conservation relation among them. Therefore, to solve for the slower relaxation time, another relation is needed. This relation is found by assuming the first step to be equilihrated a t all times while the second step responds to the perturbation. The apparent eauilibrium ouotient leiven incorrectlv in

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and linearized to provide the necessary equation. In contrast, the more correct approach is to treat the reaction scheme as a set of two coupled linear differential equations. A general solution for the two relaxation times, of which the above is a special case, can be readily derived with no assumptions. Without losing the intended audience, the appropriate mathematics for this analysis could have been introduced directly into the text, and not relegated to a few advanced expressions in a n appendix. The monograph would then have been a t once more rigorous and more rewarding for study. The chapters on results are generally good, however. Especially noteworthy is the section on the hydrated electron, the inclusion of which adds breadth to the selection of systems investigated by these techniques. The student exercises in this part of the hook are also considerably more instructive than those in the first half. Thus, "Fast Reactions" might be useful to augment a study program, but it is not recommended for use as the basis of an intensive study project. Kenneth Kustin Branders University Wallham. Mass. 02154 A Primer of Quantum Chemistry

F. C. Goodrich, Clarkson College of Technology. Wiley-Interscience, New York, 1972. ix + 232 pp. pigs. and tables. 22.7 x 15.0 cm. $12.50. This textbook provides a sound introduction t o time-independent topics in quantum chemistry. It places more emphasis on secular equations and other matrix-oriented topics than do most comparable textbooks. Nevertheless mast appli(Continued onpogeA3lOJ