A workbook of electrochemistry (A workbook of electrochemistry

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and perhaps minors is an important and rapidly growing phenomenon in chemical education. No textbook which does justice t o the breadth, depth, and philosophical implications implicit in such a course has yet appeared.

Chemistry and the Technological Backlash

James L. Pyle, Miami University, Oxford, Ohio. Prentice-Hall, Ine., Englewood Cliffs, New Jersey, 1974. xiii + 354 pp. Figs. and Tables. 15.5 X 23 cm. $11.95. Since 1970 or 1971 the number of books relating chemistry to the environment, pollution, and/or the energy crisis has increased geometrically with a doubling time which appears to he on the order of six months or less. As one librarian in a recent Punch cartoon, glancing warriedly a t overcrowded stacks, remarked to a colleague, "Do you realize that if hooks on the environment continue to proliferate a t the present rate, then by the year 2M)O. Of course one assumes that some sort of Malthusian limit will he reached eventually. In such a situation a rapid decrease in population is to be expected, from which only the fittest will emerge as survivors. One of the delights (and difficulties) of writing in this field is that there is no cansensus regarding fitness. One has nearly free rein (but also full responsibility) in deciding what to include and how to approachit. James L. Pyle has m i m e d the interdisciplinary breadth of environmental problems in the number of topics he has included in "Chemistry and the Technological Backlash." His chapter headings constitute almost an honoi roll of problems which have received copious media coverage: Energy, eutrophication, organic chemicals, pesticides, heavy metals, solid waste, trace analysis techniques, government regulation, population, food additives, drugs, and ethical and political dilemmas faced by scientists. According to the preface the book is designed t o complement and supplement any of the basic texts used in general chemistry. The level of treatment is described as being appropriate for both science and non-science majors, although Pyle does qualify this assessment with the hope that the latter will not he "unduly challenged a t times by what may seem to he chemical sophistication" and the former will not be "unduly bored by what he may see as chemical simplicity." Pyle further suggests that the text mieht be used alone for a auarter or " semester course, provided that students had adequate background.

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Unfortunately I cannot agree that any of these uses will he satisfactory. The level of presentation is'not consistent, fluctuating rapidly from high to law to high again. Far example, on page 19 in the section on photosynthesis is found the statement, "Energy levels are not unlike a stepladder, in that only certain levels are 'allowed' and the energy difference between them is definite or quantized." Two paragraphs later we read that, "Glucase occurs mostly in a cyclic structure with five carbons and one oxygen forming the ring. Four hydroxyl groups and a hydrmymethylene (CHIOH) group are linked to the ring as shown (Fig. 1.3). and hydrogen atoms complete the structure." I simply do not believe that even the better non-science majors are going to be able to fallow the latter, especially if it is encountered fairly early in the course. For science majors in the freshman course or a specifically designated environmental course two more problems arise. The factual and conceptual material is not always clear or correct. On page 24 entropy is introduced in such a way that it appears t o be conserued in a spontaneous process (largely due to the fact that only the system is considered). Numerous statements suffer from lack of good editing as on page 25, "This equilibrium, shown in Fig. 1.7, illustrates the components of this equilibrium." On page 28 we are treated to, "Coal is elemental carbon, although many hydrocarbons are present." If only it were!: No SO2 and the major man-made source of mercury in the environment eliminated! I had hoped that the broad coverage indicated by the table of contents of "Chemistry and the Technological Backlash" would make it a competitor with Manahan's "Environmental Chemistry" (see this Journal, 50 A512, 1973), whieh does not give adequate coverage of energy and solid waste problems. Unfortunately Pyle has sacrificed depth for breadth in an attempt to cater to the non-science student. For broader (though still somewhat choppy) coverage, Hodges' "Environmental Pollution" (which has not been reviewed in these pages) might he considered (demite the fact that its author labels himself as n physicist' 1 believe that the separate en\,ironmenrnl rhemistr). murse ior majors

in this Issue

. . .A453 James L. Pyle, Chemistry and the Technological Backlash John O'M. Boekris, and Ronald A. Fredlein, A Workbook of Electrochemistry . . .A453 Georee F Sekenk. Absomtion of Light and Ultraviolet Radiation: Fluorescence and Phosphurescenre i.:mwsmn . . .AKA ('mrperH Lan&d, HASIC F.qud~hriumCalcdnrions . . ACA O ~ g a n Chm:str\ ~c of 1.iir. Headings fmm 5 r i ~ n r r i t e A n z ~ r r m n 2.134

John W. Moore Eastern Michigan University Ypsiianri, Mich. 48197.

A Workbook 01 Electrochemistry

John O'M. Bockris, The Flinders University and Ronald A. Fredlein, The University of Newcastle. Plenum Press, New York, 1973. X 177 pp. Figures and Tables. 15.5 X 23.5 cm. $9.95.

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This reviewer has a strong intuitive feeling that little electrochemistry remains in the standard undergraduate physical chemistry sequence, primarily because of the seductive demands of quantum chemistry, thermodynamics, and kinetics. Although there has been a n accompanying increase in emphasis in analytical ehemistry courses, the general trend seems to be unfortunate since, as these authors convincingly demonstrate, electrochemical science can he an excellent integrating summary of physical chemistry, as well as a vital, legitmate discipline by itself. This book serves the purpose of self-instructing a topical overview of the dynamic field of electrochemical science. It is not a textbook, but is appropriately called a workbook. The authors state that the intent of this hook is to "set down a number of questions.. . to help the student of electrochemical science." It appears that such a specified audience is too narrow and that most graduate students in physical chemistry, chemical engineering, or metallurgy would profit by browsing in this book sometime during their graduate programs. The mature undergraduate student should also he able to learn from this book, after completing his physical chemistry course. This little volume certainly contains problems of numerical nature as well as derivations, but there also are questions which require nontrivial consideration of practical processes and proposed models. Not only is this a book of questions, but almost one-half of the questions have answers included which are worked out in some detail. The reviewer feels that this is a significant educational dividend since these answers can be very instructive to the reader when the material is unfamiliar or the problem seems too difficult. The mathematics used is certainly honest (the Langevin function appears on p. 15 and the error function first shows up an p. 36) but it is not flaunted promiscuously, and can usually be understood in context. It is expected that the student know, or be willing to learn, mathematical approaimations and there are several places where the interconversion of units is shown as an effective exercise. This book is definitely not a limited development of classical topics, although one can find passing reference to the Faraday, ionic equilibria, cell potentials, and free energy. Along with various questions on thermodynamics and (Continued an pageA454)

Volume 51. Number 9. September 1974

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A453

book reviews electrode kinetics, the book touches upon fuel cells, vibrational and rotational energy levels, molecular and dielectric relaxation, diffusion and random walk, the Morse potential, and the Beer-Lamhert law, heterogeneous catalysis, the Schroedinger equation (!) as well as commentary and questions an practical engineering and economics (including environmental implications). Generally, the book uses a questianand-answer format t o apply reasonable physics and mathematics to some less familiar present in the domain of electrochemical science, and i t does it very well. Since a reviewer must always find a mistake, the authors have retained a prwf-reading error in appendix 1 for the mass of the electron. E. Miller Layton. Jr. Iowa State University Ames, Iowa. 50010

strong acid and strong base (and silver and chloride ions by analogy), one with any mixture of a weak acid plus its conjugate hase, illustrating iterations, and one for linear least squares. A Project section purports t o apply equilibrium calculations to a model d a natural water system, considered merely as strong acid added to a bicarbonate buffer. Overall, it is the opinion of this reviewer that computer programming is more effectively taught without such full integration with the chemistry on a page-by-page hasis. However, it is certainly worthwhile to see an introduction to programming which is hasedon chemical systems. R. W. Rarnette Carleton Co//ege Northfield, Minnesota 55057

Absorption of Light and Ultraviolet Radiation: Fluorescence and Phosphorescence Emission

George H.Schenk, Wayne State University. Allyn and Bacon, Inc., Boston, 1973. xii 312 pp. Figs. and tables. 21.5 X 14 cm. $6.50.

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BASIC Equilibrium Calculations ('uc,pc,r H Long/-(r.rd Carleton Lnivrrsir y , Addijon-Weslev Publishing Cu , Reading, Mas,.. 1973. xiii + 76 pp. Figs.

and tables. 28 X 21.5 em. $2.95 The author attempts t o do three tasks simultaneously in this discussion of (a) chemical principles of simple equilibrium systems, (b) mathematical principles of the strategy of calculations, and (c) programming principles based on the Basic language. Such an integrated approach has some intrinsic merit, but there is a risk that the student will he confused by the continuous change of hats required. The algebraic approach is to find n equations for the n unknowns, using the equilibrium constant expressions, the electroneutrality rule, and the material halance expression, and to combine these in ways which lead to high-order equations which can be solved by computer iteration. The chemical systems include strong acids and bases, weak acids plus their conjugate bases, and silver chloride, the latter without reference to chlaro-complexes. There is a certain deliberate perversity (the author's word) in symbolism. For example, in contrast with custom, zero is written 0 and the alphabetical letter is written 0.When an equal sign is used for a mathematical equality it is placed in quotes, "=," whereas the equal sign in Basic statement, where i t does not denote equality hut rather "replace w i t h is used without quotes. However, this distinction is frequently not followed in the text. In specifying subscripts for acid and base, the authors say in a footnote, "We might have made things easier to remember by calling "1" the acid and "2" the hase since A comes before B. But, the reue7.w choice is meant to help you remember that C2 does not equal A!" The text includes three Basic programs whieh serve well for discussion of prineiples. One deals with any mixture of a A454

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Journal of Chemical Education

In contrast to the title's suggestion, this book has a distinct hiss toward photoluminescence. The last five of the seven chapters introduce the reader t o the phenomena of fluorescence and phosphorescence in organic and inorganic systems and carry him through analytical applications and instrumentation. The first two chapters concern absorption processes, but one senses throughout that they exist to serve the exposition on luminescence, because they include no discussion of instruments or applications and almost none on traditional topics such as the WoodwardFieser rules. The hook is cast toward readers who have had no first course in physical chemistry but who do have a n elementary knowledge of molecular orbital theory. Given the rather marked slant toward the analytical utility of luminescence, the potential market is mainly sophomares and juniors enrolled in analytical chemistry courses. Presenting this material on the chosen level is a very difficult job, and Professor Schenk has made a novel and ambitious effort. Thus i t is unfortunate that serious breaks mterrupt the logrcal flou from t m e u, ttme Two of several example, mclude an examination of the relation hetween fluorescence yield and the radiative and intrinsic lifetimes without construction of the kinetic framework whieh gives the relation meaning, and a treatment of the kinetics of intersystem crossing and bimolecular quenching which arises almost 30 pages before these processes are even defined. A more serious objection concerns the order in which the author examines the absorption spectroscopy of organic molecules and complex ions. The pedagogical choice to discuss the latter first is based on his desire to present the d' T i I H 2 0 ) ~ + ion 3 as an initial example featuring no complications from spin permutations. The advantage is gained only to be lost in the intricacies of complex ion spectroscopy. The reader is whisked rapidly through sketchy discussions of crystal

fields, spin pairing rules, strong and weak field complexes, and charge-transfer absorptions. Professor Schenk must ultimately treat the spin perturbations in any event, and it certainly seems to this reviewer that he might have started better with the simpler spectroscopy of the organic species. Some annoyance also arises from factual and typographical errors, inconsistencies in usage of numerical values and dimensions, and imprecise exposition, especially with regard t o derivations. Each of these categories seems to contain an abnormally large number of members, but the transgressions are rarely fatal t o a presentation. The most seriously compromised discussion pertains t o the Franck-Condon principle. This essential precept is never eaplained cogently, and one finds its elements and consequences scattered throughout the text and Appendix E. Despite these shortcomings, the book has several positive points. Among the basic aspects, one can cite excellent attention t o the significance of the dual nature of light for absorption spectroscopy and t o the factors affecting transition pmhabilities. The subleties involved in characterizing excited states of carbanyl compounds are esoeciallv well illuminated. The book disnlavs its best form in its eoveraee of an~~,~ al>.tical tupics such 2, rhe implicnrions of inrensity-concentrath relarwnships fur luminescence. Details of measurement receive competent treatment in sections which rather heavily emphasize filter-oriented instruments. Each chapter closes with numerous original problems, many of whieh are based an recent literature. They vary substantially in quality, but some very good ones are available. The comments above will support this reviewer's opinion that instructors and students working on a level above the first physical chemistry course will not find this text a satisfying introduction to luminescence. Below that level it could be useful, and any instructor in such a circumstance who wishes to cover the subject in some detail ought toexamine it.

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Larry R. Faulkner Department ofChemistry University 01 Illinois Urbana. 67801

Organic Chemistry of Life. Readings from Scientific American With introduction by Melvin Caluin, University of California, Berkeley, and William A. Pryor, Louisiana State University, Baton Rouge. W. H. Freeman and Co., San Francisco, California, 1973. xii + 452 pp. Figs. and tables. 22 x 29 cm. Cloth $12.M); paper $6.95. Thirty-eight articles are reprinted, collected under the headings: Biological Regulators (15 pages), Macromolecular Architecture (13 pages). Cellular Architecture ( 3 pages), and Chemical Biodynamics. This is a successor to the previous collection "Bio-Organic Chemistry." Additional bibliographies and a good index are supplied. WFK