Elemenls of Slatirlical Thermodynamics
Leonard K . Nash, Harvard University, Cambridge. Addison-Wesley Publishing Ca., Reading, Mass., 1968. viii 128 pp. 52.50.
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Leonard Nash has a remarkable and rare ability to orient his teaching toward a single general and fundamental concept. I n teaching freshman chemistry, this concept is the position of chemical equilibrium. I n "Elements of Chemical Thermodynamics" (ECT), he pared away all the irrelevant and tangential parts of thermodynamics, the elegance of those parts notwithstanding, and led the bright h u t ignorant freshmen as directly as possible from the First and Second Laws of Thermodynamics to the thermodynamic derivation of the equilibrium constant. He did this clearly, gracefully, and with great physical insieht. "Elements of Statistical Thermodynamics" (EST) is the natural successor to ECT. I t goes one step deeper into the problem, to develop an understanding of equilibrium a t a microscopic level. This volume is almost as successful as the earlier text. I felt thst the new hook lacks a little of the grace and elegance of its predecessor. On the other hand, when "Elements of Chemical Thermodynamics" was written, thermodynsmics was already a well-established part of several freshman courses; many of us thought we had a rather clear idea of what was hard and what was easy, of where one could go rapidly and where to be slaw. The natural organization of the material was perhaps becoming clear to us all. Teaching statistical mechanics to freshmen is a. different matter. Very few people have even tried to present it s t the elementary level in any way approaching the depth thst Nash does. He clearly developed his orgsniz* tion during the three years to which his preface refers and found from experience what parts were hard or easy far his students. The result seems to me to be a bit labored in a few spots and perhaps a bit terse in others. Some of the concepts like those of an ensemble, of weak coupling, and of the problem of symmetry in homonuclear diatomics are treated with a bit less precision than the thermodynamic concepts of the first book. On the whole, the new book has the same strong direction and ohemied flavor as ECT. Like its predecessor, it is a pleasure to read. The treatment moves from mathematical tools to physical models and phenomenological equations, then to specific chemical examples and finally to the kind of generalization that we associate with physical insight. The g o d is clear and explicit: why, in terms of the mieroacopic properties of reactants and produck, does a particular chemical equilibrium lie where it does? By taking this viewpoint, rather than simply asking his students to learn how to calculate equilibrium constants from partition functions, Nash does a very important thing. He establishes, a t the freshman leuel, the bridge between the quantum-theoretical treatment of molecular structure that has so dominated high school and first-year college chemistry, and the macroscopic world of descrip-
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Journal of Chemical Education
tive chemistry. The other freshman-level treatments of stat,istical mechanics with which I am familiar (and there are certainly some that I haven't examined) fall far short of making this bridge. They simply don't go deeply enough into the subject to eslabliah the relations between microscopic energy levels and thermodynamic quantities, the state variables and heat capacities. As a result, other treatments cannot get to the calculations and, even more important, to the order-of-magnitude estimates that constitute the connection between the micro and macro worlds. They can only make imprecise qualitative mguments to get these quantities. And i t has been my experience, especially with freshmen, that the greatest source of confusion and misunderstanding among chemistry students is imprecise ideas of fundamental concepts. One needs a treatment a t least rtt the level of "Elements of Statistical Ttiermodynamics" t o show what really makes molecules dissaciate, or how energy and entropy eontribute to an equilibrium constant, how these contributions change with temperature, and how they originate in the properties of molecules. Certain parts of the book particularly pleased me; I liked the discussions of microstate and configuration, and the derivation of the equation of state of the ideal gas. I was sorry there was not more discussion of equat,ions of state and their roles in thermodynamics and statistical mechanics. The problems a t the end of the book are verv much in Naqh's stvle~" ingenious, challenging, and represent,ative of all facets of the material, from derivat,ions to explicit molecular calculations. I would like very much to see serious statistical mechanics incorporated into the earliest parts of the normal chemistry curriculum. American chemists have tended to slight this subject since the days of Gihbs. I n so doing, we avoid a subject that ought to be a keystone in the basic chemical curriculum. The fact that thermodynamics is older or that descriptive chemistry (meaning memorization with the help of the periodic table) is supposed to give us intuition, is no excuse for avoidi n g t h e issue. da dam en tally, to understand chemical phenomena quantitatively in terms of moleolllar properties, we must use statistical thermodynamics. And "Elements of Statistical Thermodynamics" is a very good place to start.
in the number of preparations that are short, simple, and safe enough for use in general or inorganic chemistry laboratory courses and a corresponding increase in the number of cpmplicated preparations requiring elaborate equipment and safety precautions as well as excessive expenditures of time. Emphasis has shifted from relatively stable ionic compounds of the metals to more unstable orgsnome:allics and covalent eompounds of the nonmetals. "Inorganic Syntheses," in its last half dozen volumes, has faithfully reflected this trend. I n the vernscular, the series shows "where the action is." Consequently, instructors of lower level courses with iqexperieneed students and limited facilities should he warned that they will not fin3 here many experiments suitable for their needs. I n line with the increasing complexity mentioned above, the starting materials for a. number of the ~ r e ~ a r a t , i o nins this volume are rtctuallv
involve elaborate apparatus, and the praductr or starting materials are toxic, corrosive, flammable, explosive, p y r y phoric, hygroscopic, or sensitive t o aw or moisture (safet,y precautions, as in previous volumes, are prominently provided). Inasmuch as "Inorganic Syntheses" is not intended primarily for instructional use, these deficiencies should not be construed as criticism of what is undoubtedly a. significant contribution to a most useful series. The present volume contains 42 contribution~ which describe 92 diversified compounds. The general organization of the series is discussed in previous reviews [See 3. CHGM.EDUC.,38, A552 (1961); 40, A530 (1963); 44, A354, 624 (1967); 45, A436 (1968)l. The former pract,ice of dividing the book into chapters hased upon the Mendeleev periodic elapsification has been abandoned. Volume 11 consists of six chapters dealing with areas of considerable current research interest. The first and shortest chapter (14 pp.) is devoted to the high-temperature syndhesis of very pure solid-state compounds, which are becoming increasingly important for theoretical studies and industrial applications. The technique of high temperature chemical t,ransport is employed to prepare single crystals of CdG a A and Fer04, but few students would R. STEPHENBERRY be patient enough to wait the ten days University of Chicago required t,o grow crystals of the lst,ter Chicago, Illinois compound. As in Volumes 9 and 10, an entire section (Chapter 2, 30 pp.) is allot,ted to boron-hydrogen compounds. The third and longest chapter (64 pp.), Inorganic Syntheses, Volume 11 the one which includes mast of the preparations simple enough for instructional William L. Jolly, Editor-in-Chief, Uniuse, describes those perennial favorites versity of California, Berkeley. McGraw-Hill Book Co., New York, 1968. of the inorganic laboratory course-the coordination compounds. Several of 231 pp. Figs. 16 X 23.5 cm. xii these compounds, e.g., [Cr(en)s] [Ni$10.50. (CN)sI and K,[Mo(CN)sI, exhibit unI n the last few decades, synthetic inusual coordination numbers. I n this organic chemistry, like the world in which sect,ion also, ruthenium, the last of the it functions, is becoming more complex, platinum metals to be included in "Insophisticated, and dangerous. Comparorganic Syntheses,'' makes its debut with ison of the latest volume in this wella versatile intermediate, K,[Ru2Cho].known series withvolumes publi~hedin the H,O. 1930's and 1940's reveals a sharp decrease (Continued on page A 4 4 ~
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