Introduction to nuclear chemistry (Carswell, D. J.)

Introduction to nuclear chemistry (Carswell, D. J.)pubs.acs.org/doi/pdf/10.1021/ed044p701by WH Jones - ‎1967in entropy, A...
18 downloads 0 Views 3MB Size
that first used by Lewis and Randall, in that it begins with a definition of t o t d entmpy increase in an irreversible process, rather than with the classical concept of entropy change within a reacting system in a reversihleprocess. Dr. Luder's approach differs from tbat of Lewis and Randall, however, in that his definition of total entropy increase is based upon the energy irretrievably wasted in the irreversible process, rather than upon the restoration of all systems ooncemed to their initial states. Specifically, Dr. Luder first defines a reversible process for carrying out s. given spontaneous change as one tbat supplies the maximum possible amount, wr, of work, and therefore involves the absorption by the reacting system of the maximum amount, y,, of heat, or evolution of the minimum amount. The total increase in entropy, ASs*,, of system and surroundings in an irreversible process is then defined as the amount of work that might have been done, but was not, or the amount of heat that need not have been evolved, but was, divided by the dmolute temperature rtt whieh the change has oocurred; that is, AStmu, = (y, qi)/T. This t o t d entropy increase is then spportioned between system and surroundings in accordance with the eqwtion

-

in which - p i denotes the amount of heat given up to the surroundings in the irreversible process. This approach then leads by simple and logical steps to the identification of the free energy decrease, defined by the equation - AG = T A S AH, with the maximum net work that the spontaneous reaction e m provide a t constant pressure and temperature. Noteworthy throughout the exposition just discussed is the author's scrupulous concern for the precise use of words, exemplified especially by his sharp distinction between the terms "spontaneous change" and "irreversible process"-a distinction too often overlooked, even at this latedate, by other writers. The remainder of the second chapter, and all of the third, comprise a fairly conventional treatment of methods for the determination of AG, of its variation with temperature, of the derivation of the law of chemical equilibrium, and of the application of this law to reactions between gases and between nonelectrolytes in solution. Chapter 4 consists of an ext r a o r d i n d y thorough treatment (42 pages) of the nonthermodynamic properties of solutions of electrolytes. The discussion of electrolytic conductance, in particular, is considerably more extensive than those commonly found in textbooks of physical chemistry. In view of this fact, it is somewhat. surprising that the treatment in Chapter 5 (21 pages) of the themodvnamics of electrochemical cells

there is no discussion of reference states, in terms of molality or wncentrrttion, for activity coefficients of solutes; nor ( d e

spite the fact that values of the activity coefficientsof zinc and lanthanum chlorides are given in Table 5-2) is the mean activity wefficient of an electrolyte of other than 1-1 type anywhere defined. The chapter concludes with a single paragraph on electrometric titration, which is too brief to be useful. A considerable number of well-chosen problems is given a t the end of each chapter. Errors, typographical and otherwise, are not numerous, and, for the mast part, not serious. Inaccuracies that might well perplex or mislead the unwary student include the statement on page 15 that "an ideal gas has no chemical composition" and on page 17 that "For an ideal gas, CVis "/I R" ; also, on page 79, the omission of the exponent 2 on CNO,in Equation (3-96). The solving of Equation (3-91), page 76, does not require the use of successive approximations, since it may readily be reduced to s quadratic by the simple expedient of taking the square root of both sides. Many readers will question the desirability of the author's scrupulous avaidance of the terms cathode and anode on the grounds that "disagreement exists in their usage" (page 136, footnote 1). It is true that these words cannot be satisfactorily defined in terms of the sign, or -, applied to the electrode. However, if the anode is defined either as the electrode from which electrons emerge into the external circuit or as the electrode a t whieh there is oxidation, and the cathode as the electrode a t which electrons enter from the external circuit or as the electrode at which there is reduction, there can be no ambiguity or disagreement. As was implied in the first sentence of this review. the book is not intended to

Cht~pters3 and 4, after listing six nuclear reaction types! proceed with the origin and kinds of rad~ations. the occurrence of natural radioactive series, and the characteristics of alpha, beta, and gammaemissions. Opportunity is taken in these 48 pages to present activation analysis, as well as the quantitative aspects of the decay law, daughter growth, and equilib-

rium.

Chapters 5 and 6 employ 44 pages to discuss radiation detection and measurement, and the design m d capability of availsble instruments, including gas ionization, scintillation, and solid state detectors. Logically included are explanations of phosphors, photomultipliers, semiconductors, analyzers, seding tubes, and basic electronic circuitry. Chapter 7 is on radiation chemistry, while chapter 8 discusses the measurement and separation of isotopes; together they total 47 pages. The former outlines dosimetry methods, then considers the interaction of radiation with molecules, whether solid, gaseous, or liquid. Resulting reaction michanisrns aresuggested involving ions, excited molecules, and free radicals. The latter chaoter develo~sthe principle and several deiigns of the mass spectrometer, and illustrates the variety of problems this equipment e m solve. The final section briefly treats isotope separation, outlining seven methods in as many pages. Chapters 9 and 10 in 48 pages deal with accelerators (Cockroft-WaIton, Van de Graaff, h e a r , cyclotron), with neutron sources (radioactive, accelerator, reactor), with the actinides (origins, preparations, chemical properties), and finally with uses of radionuclides (tracers, radiation sources. dating). The eleventh and final chapter is a laboratory manual of 40 pages. After .trrAr,p, rdiution pncautions, ir delucid presentation of the wncepts of svribes thr major spvrialircd tcchniqws. entropy and free energy, it will be most It then eonrludes with inatrucriww for 16 useful as supplementmy reading in a selected radiochemical experiments, rangcourse in physical chemistry, or in s. ing from the properties of radiations to firsbyear course in general chemistry gamma spectrometry and activation analthat includes an introduction to chemical ysis. thermodynamics. The style of Csrswell throughout is simple, direct, and uncluttered. Illustrsr ARTFLuRW. DAVIDSON tions are in the form of charts and drawRaker University i n p rarhrr than photop,mph=,and clearly Baldwin City, Kansas I n . ( . ' ~ x I I ~ Qi n* the chuicc atgd conrinui ~ c,f y topic.; wuld br ti.iggwrd, hut coverage and sequencing are always matters of opinion. The material presented is reguIntroduction to Nuclear Chemistry larly modem, though thesection on isotope separation does not reflect today's signifiD. J. Carswell, University of New South cance of the centrifugal method. Wales, Kensington, Australia. AmerErrors are few, and largely typographican Elsevier Publishing Co., Ino., New i d P q e 91 writes "1 part in 10-"" 279 pp. Figs. and York, 1967. ix when 10" is meant. The bottom line of tables. 14.5 X 22 om. $11. page 142 s e e m to have been corrected Author Carswell directs his book to the after the plate was made. Page 63 refers chemist usingnuclear methods, rather than to "nuclei of the same mass number" then to the nuclear scientist. The goals set are uses U-235 and U-238 as an example. limited, and the presentation *voids great A large shortcoming of the book is its detail. Any evaluation of the book must lack of supplementary material and study be in light of these avowed objectives. aids. At the end of s chapter one finds no Moving swiftly, the first two chapters numerical problems, no suggestions for fursketch in a span of 46 pages the developther study, no literature references. The ment of today's ideas on atomic and nuappendix has no table of nuclides; indeed, clear structure, the more useful subatomic there is no appendix. If the text itself particles, nuclear magnetic resonance, were more inclusive these supplements binding energy, and liquid drop versus would be less missed; as it is, the omisshell theory. sions are serious.

+

+

Volume 44, Number 1 1 , November 1967

/

701

Analysis will show that all major criticisms of the book hinge essentially on its brevity. The teacher has constantly the feeling that the treatment, if not inadequate, is certainly sketchy; that too much is left unsaid. Yet how much can be said in just275 pages of large type (12point)l But remember, Cerswell's purpose is an "Introduction," a. book for the non-specialist. Operating within this framework, he keeps it simple, and acquits himself well.

In general the author has presented a satisfactory outline of the reactions of free radio&. There are, however, many sections wherein the discussion should be treated with reservation. For example, the discwion of 1,Zhalogen migration does not even mention the alternate, and often preferable, elimination-addition mechanism. GLENA. RUSSELL Imuo S M e University

WILLIAM H. JONES E m ~ Univern'ty y Atlanta, Georgia Magnetic Susceptibility

Free Radicals

W i l l h A . P ~ y o rLouisiana , State University, Baton Rouge. McGraw-Hill Book Co., New York, 1966. xiii 354 pp. Figs. snd tables. 16 X 23.5 om. $12.

+

The prefbce 15 t h i ~volume indicates an attempt to outlinc the entire firld of free radirnl chemlsrrv at n n nrrodwrorv level. I feel that the en& area bas not bein completely covered and that this volume would he more properly entitled, "Reactive Free Radicels in Solution." In psrticular, the work an stable free radicals from Gomberg's time to the present is poorly treated or ignored completely. Thevolume is divided into four parts entitled The Nature of Radicals, The Production of Radicals, Reactions of Radicals, and Terminrution Reactions. Chapter 2 on thr 1)erecrion of Rndirnl;, includil~gelectron paramngneti,! rconnnw, is particularly weak even in basic definitions such as theBahr magneton and thegvalue. In addition to the chapter on De tectian of Radicals, the first part of this hook contains a. reasonably goad chapter on Conformation of Radicals and a brief chapter on Energetics and Rates of radical reaction that does not mention the classical concepts of M. Polanyi. The chapter on Conformational Analysis suffers by not considering fully tbe data now available from esr spectroscopy. For example, the geometry of the vinyl radical is not mentioned. Thedifferencebetween confieuration and conformation is not adequately treated for a book that purportedly emphsi sizes basic principles. Part two considers the production of radicals via photolysis, thermalysis and electron transfer. This is a. reasonably complete review and is written in a pleasing manner. The third section of this volume wnsiders Reactions of Radicals. Aliphatic and aromatic substitution reactions are adequately covered as are s variety of addition reactions including vinyl polymerization. Chapters on polymerization, oxidation, and inhibition make this volume worthwhile to a student interested in the more practical aspects of organic chemistry. Consideration of diradicd~such as methylene in Chapter 19 seems out of place in a volume of this type. Part four is entitled Termination Reactions and appears to have been added as an afterthought.

702

/

Journal o f Chemical Educofion

L. N . Mulay, Pennsylvania State University, University Park. Interscience Publishers ( a division of John Wiley & Sons, Inc.), New York, 1966. 132 pp. Figs. and tsblebles. 14 X 21.5 em. Paperbound. $2.95. There are severalseries of volumes whieh make some attempt to cover an area of chemistry comprehensively and which include a chapter on magnetic susceptibility. That there is much duplication in these various treatments is inevitable. That the emphases reflect the interests of the authors and the purposes of the particular series for which they are writing is also to he expected. The oresent volume is a r e ~ r i n tof s chalwr' in the ~ o l t h o f f - ~ l v i.Trmtisr u~' or) Analytical Chr~niatrgPart 1, Volurw 4." Approximately half of the book i. d c voted to an exposition of the 1henr.v and principles which form the bassof mapeti? measurrmente. The other half is devoted to experimental techniques and to examd e s of analvtioal annlications. The emphwis is or, the ride scopp of ehemienl prolkn>ewhich have heen studied by mngw t t v suereptibiliry measuremcnrs rather than on exhaustive discussion of particular topics. Thus, although the most extensive use of magnetic susceptibility has concerned the str"ctures of metal &mplexes, this topic is treated in three pages, mainly from the valence bond a ~ ~ r o a with e h onlv the barest mention of li'gand field theory. By and large, the author has done a good job of presenting the material within the limits of the objectives for whioh it was written. The discussion is well organized; it is usually clear despite an occasional bit of awkward phraseology and an enforced brevity that sometimes interfere. A valuable feature is the inclusion of detailed cdculations from the experimental data. whioh are given for several significant chemical problem. Numerous references to the original literature through 1962 are given. Though supplementary references have been added in thereprinting, they are all to the author's own recent papers. A number of typographical errors remain, hut they are in general not serious. One of these is the repeated use of K for the Boltzmann constant. The method of indicating the sign and magnitude of the ionic susceptibilities in Table 38.X is confusing. Although the phenomenon of magnetic susceptibility has been known for a long time, it is onlyrecently that its applications to structural problems have been widely used by chemists. Aa recently as ten years ago, the topic was seldom even men-

..

tioned in s n undergraduate physical chemistry textbook. Happily this situstion h ~ s now changed. The wailability of this brief volume will also help to remove msgnetic susceptibility from its previous state as a "poor relation" among instrumental methods. I t is doubtful that it will be widely adopted as an undergraduate text except possibly in a "special topics'' course. It will probably find its greatest use a8 a suggested supplementary text for the student who is particularly interested in the subject, and as a place to begin for the research worker who is making magnetic measurements for the h t time. B. R. WILLEPORU Bucknell University Lmisburg, PansylYania Chemical Binding and Structure

J. E. Spice, Winchester College, England. Pergamon Press, Inc., New 395 pp. Figs and York, 1966. xiii tables. 13 X 19.5 om. $4.50.

+

This hook is a corrected printing of the 1964 edition. I t is part of a series aimed at first- and second-year college students and presents a concise qualitative account of chemical bonding and structure. Ten chapters of the book cover tbe development of quantum chemistry, the periodic table, ionic and covalent bonding, molecuIar geometry, transition metal and electron-deficient compounds, electronic structure and chemical reaxtions, and structure and bonding in crystals. The last three chapters discuss various methods of structure determination. A short bibliography, a set of 67 problems (which are referred to in appropriate places in the text), a table of fundamental constants, answers to about hdf of the problems, and an index are appended. While muoh of the book covem items usually encountered in freshman ohemistry, the broad spectrum of topics, espeoially the chapters on structure determination, and the level of presentation make the book suitable as supplementary material for a high school or freshman course. The wealth of illustrative material, lucidity of presentation, and reasonable cost will be welcomed by students. The book is ruggedly constructed and lasts through handlings by several people. JOHNR. WASSON Illinois Institute of Technology Chicago An Introduction to the Theory of Molecular Structure

JeunJoseph Cha~eUe, University of Lovaniom, Leopoldville, Congo. Reinhold Publishing Corp., New York, 1966. 188 pp. Figs. and tsloles. 15.5 xii X 23.5 em. $7.50.

+

The title of this hook is slightly misleading; it could better he described as an introduction to the theory underlying spectroscopic methods of studying molecular structure, including eleotronic, vibrational, and rotational spectra. The book is concise, and presents many results without

(Continued on page A.994)