Chapter 6. This discussion, together with those that precede it, should thoroughly prepare the student for the treatment of reversible reactions and chemical equC librium that follows in Chapter 7. Important points about chemical equilibrium are established with the aid of two wellchosen examples, one simple, the decomposition of hydrogen iodide, and one more eomolex. the deeamoosition of nitraua ' acid: The hook closes with brief, but readable chapters on catalysis, very fast reactions, and the use of isotopes. Also included is an Appendix on the meaning of the signs, =, -, 8 ,e;n useful Glossary; and a nice list of 34 articles on kinetics culled from Chemical Reviews, Quarterly Reviews, ~ n l JOURNAL, s and Seientifrc American. It should be noted, finally, that often much can be inferred about the effortand imagination that has gone into a.book from its problem. King's problems are "first rate." They make an excellent contribution to a fine volume that should find wide use among students of chemistry.
HENRYA. BENT University of Minnesota Minneapolis Elementary Chemical Thermodynamics
Bruce H. Mahan, University of California, Berkeley. W. A. Benjamin, Inc., 155 pp. Figs. New York, 1963. x and tables. 14 X 21 em. Pe+peperhound. $1.95. The conventional general chemistry course contains much concealed thermodynamics. Included, for exemple, are solubility products, ionization constants, and other constants of chemical equilihrium; oxidation-reduction potentials and electrochemistry; vapor pressure; freezing point lowering and boiling point rise effects; osmotic pressure; and Le Chatelier's principle. These applications of thermodynamics are capably described from s. (primarily) clc~ssicalpoint of view in this volume, which, although it introduces no major new physical and pedagogical insights, does contain a number of nice touches. Taken together the latter add up in the reviewer's opinion to a successful trettment of chemical thermodynamics for beginning students who have had, or are currently enrolled in, n beginning calculus course. (Mshan's book is the only one of the four reviewed that presumes a knowledge of calculus.) The book is divided into four chapters: an Introduction, the First Law, the Second Law, and Applications. The Introduction is s. business-like, and happily brief, discussion of several of classical thermodynamic's characteristic concepts (macroscopic properties, systems, states and state functions, equilibrium states, and temperature scales). In the second chapter, the First Law is introduced-with the aid of Newton's law and several integrations of "mathemrttically defined" work-in the familiar form AE = q - w and illustrated by readable discussions of thermochemistry, enthalpies of formation. bond energies, heat capacity, temperature dependence of AH, explosions and flames, and P - V cdlculstions on ideal gases. The last topic, though
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Journol of Chemiml Education
particularly well-worked out, prabably will not greatly fire the imagination of beginning students-a statement more about beginning students, perhaps, than about thermodynamics. In the third chapter, after discussing the need for another law with three examples (the free expansion of a gas, heat flowiromhot to cold, and theirreversible reaction of hydrogen and oxygen), the Second Law is introduced, rather abrupbly. in the form
chemistry who have enjoyed within recent years a conventional course in physical chemistry will probably wish to examine this book. The publisher is to be congratulated uoon the rare meed with which this book was put into print.
HENRYA. BENT University of Minnesota Minneapolis The Structure of Molecules: An Introduction to Molecular Spectroscopy
This is followed by several illustrative examples (reversible isothermal expansion of an ideal gas, free expansion of an ideal gas, and heat flow), a molecular interpretntion of entropy (S = RIN In R), and the deck-of-cards analogy ("The fundamental reason why the shuffled &ate is found after mixing tbe cards is that there are many microscopic states that are consistent with the shuffled condition and only one that is consistent with the ordered state.") In this way the author sidesteps what often becomes for the beginning student a. traumatic experience with Carnot's cycle and integrating factors. Completing the chapter are conventional, well-written discussions on the Gibbs free energy, eauilibrium constsnts. electrochemied e&, and the temperature dependence of equilibria. In the last chapter (Applications), the book reaches a climax. A subtitle for this chapter might be: General Chemistry From the Vantage Point of the Second Law. Developed there are those applications of thermodynamics mentioned in the first paragraph of this review. The hook contains a very generous set of well-thought out problems. Inclusion of answers to selected problems would probably increase the book's vdue to the student. Alan, while early in the book there is introduced the statement "The entropy of the universe increases," this statement is not fallowed up syatemeticrlly; indeed, the simple relation between the entropy change in the universe and the free energy change in s chemical system is nowhere mentioned. Furthermore, as is almost universal with textbooks on thermodynamics, there is conveyed the impression that the equilibrium condition for reactions occurring st constant volume and for reactions occurring at constant pressure are different; in fact, for a system that is in hydrostatic equilibrium with its surroundings, [ A ( E - TS)IT.V = [A(E - TS p V ) l r . ~ . In addition, the relation between a substance's activity and its partial molal entropy is not explored; one of thermodynamic's most useful applications, the explicit form of equilibrium constant expressions, is, therefore, not developed, but mumed. To be meaningful the early discussion of the relation between the conservation condition and state functions should include a comment on the distinction between intensive and extensive properties. The text sometimes does not follow the recommendstions of a recent letter in Sciace on "I, We, One, and Preaently." On the whole, however, thisis avery well executed hook, tbe best of its kind the reviewer has seen. Teachers of general
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Gordon M. Barrow, Case Institute of Technology, Cleveland, Ohio. W. A. Benjamin, Inc., New Yark, 1963. xi 156 pp. Figs. and tables. 14 X 21 em. Paperbound. $1.95.
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Few studies have contributed more to the advancement of physical science than have studies of the interaction of radiation with matter. From the early contributions of X-ray spectroscopy t o our understanding of atomic structure and the periodic table through the common dayto-day uses of the absorption of visible light by colored compounds to the recent socurate determinations of molecular parameters by microwave speotroscopy, the interaction of radiation with matter haa been an important tool in the study of the structure of matter. Today with the introduction of spectrometers in increasing numbers and variety into chemical laboratories, very notably into undergraduate teaching laboboretories, the appearance of a book on molecular spectroscopy at the beginner&' level is timely . indeed. The book's title, "The Structure of Molecules," is somewhat misleading. Its contents are more aceuratdy described by the subtitle. More than half the book is concerned with the rotational and vibrational spectre of diatomic molecules; only one page, per se, is devoted to the geometrical shapes of molecules. The book is divided into six chantelm. I n the first chapter the reader is intr&uced in eighteen densely packed pages of text to the wave nature of radiation, the quantum nature of radiation (18 lines), Planck's relation, the electromagnetic spectrum, methods of measuring the absorption of radiation (sources, dispersing elements, detectors, choppers, and doublebeam operation), degrees of freedom (tmnslrttional, rotational, vibrationd, and electronic), quantum restrictions, and Boltzmann's relation. , - . cdculation of the internuclear sepa%tion i n carbon monoxide from the moleculz's
vihretiand spectrum of carbon monoxide and the determination therefrom of its farce constant. In none of the chapters of this book is a knowledge of calculus required. (It is assumed, however, that the reader is familiar with the meaning of "erg," "dyne," and "f = ma!') (Continued on page A501
BOOK REVIEWS I n the fourth chapter these results are combined in x nice discussion of t,he simultsneous rotation and vibration of diatomic molecules. The high point of this chapter is the calculation for m r h m monoxide of the internuclear sepnmtion in the fourth vibrationd level. Thelnst two chapters are concerned with the electronic energies of molecules. The fifth chapter contains an interestingly detailed discussion nf t h e electronic: encit,atinn of iodine vapor and briefer, qualit,ative discussions of the electronic spectra of conjugated hydroearhons, enrhonyl eompounds, and actahedrally coordinated metal ions. Fluorescence and phosphorescence are described in the sixth chapter. The hook contains thirty problems, some with answers, and numerous illustrat,ions. Several of the latter unfortunately appear t o have been printed directly from an a ~ t i s t ' sunchecked drawings nf rough sketches. On page 17 the units on (3/2)RT ore incorrect. Moreimportant, s hook on spectroscopy for beginners encounters in a part,iculerly challenging form the problem of maintaining cont,aet with t,he readers' previous experience. While the mathemnticsl sections of the present honk have generally been skillfully held a t a n element,ary level, beyond t h a t the text offers t o the general reader few amenities. Prnrtieal applirations and helpful analogies are rather sparingly given. The reviewer noticed only five brief digressions of this nature. Mare
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would he appreciated. Mention might be made, for example, of the physical reasnnnhleness, hased upon the well-known properties of radio waves, the effects in photography of visible light, the tanning rexct i m induced hy ultraviolet light, and the dangers of overexposures tu X-rays, of Planck's rendion = hu. A similar discussion could he given for t h e qualitative generalization cited on page 23 regarding the spacing of quantum-mechnnicnlly allowed energy levels. Also of interest t o the lay reader might he the relation between degrees of freedom, heat capacities of gases, and the 1,sw of lhdong and Petit. Another possihilit,y concerns the compnrisannftheequationsuf motionofarigidrr,t,or with those of Bohr's model of the hydrogen atom. Some of these points "right, he hrought out in prohlems t o the approprist,e chapters. Teachers using Barrnw's hook will also find useful the lrmg version of the prize-winning film on muleclllzr spectruscopy developed by Professors Cr.zwford and Overend for the Chem Study Pnlgram. This hook, perhaps the first of its kind, should properly be judged, however, from the perspertive of its over-all pedagogical uhievementa, which are cansiderahle. For hetween the raw data of spectroscopy and, for example, t h e length of a chemical Imnd lies that formidnlde mathematical model, quantum mechanics. The manner in which Barrow tackles this mathematical
