Physico-chemical constants of pure organic substances. Volume 2

Publication Date: May 1966. Cite this:J. Chem. Educ. 43, 5, XXX-XXX. Note: In lieu of an abstract, this is the article's first page. Click to increase...
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the IBM 1620, and the ALGOL translations are virtually worthless since the programs would need to be extensively r e written before use on other computers to avoid extreme waste of time. The second consideration is the types of programs provided. For the most part these are rather simple calculations such as interpolation of densities, mole fractions, and the like, and the fitting of parameters for conductance, viscosities, and the GibbsHelmholtz family. The authors have also been interested in variations on the theme of finding equilibrium constants from spectral data. The programs tend to be general in the trivial sense of stringing together an assortment of rather special ealculstions which are elected by suitable control punches. The third consideration is the ease with which the programs can be used. There is relatively little explanation of what is b e ing calculated, and hence it is often necessary to read the FORTRAN statements to find out. I t would have been most useful to have examples of worked out problems. Moderately expert programmers with ohemicsl background will find it troublesome to nrenare a data. deck far most of the programs. Non-programmers will have %roughtime. The programs put an excessive burden on the user since there are few or no internal checks for errors. A wild punch might easily cause s. subtle misealculstion. The only tvpe of user that might benefit somewhatfrom these volumes isan expert programmer who is interested in certain forms of spectral or special kinetics calculations. They are definitely not recommended for the average user nor for the library with a limited budget. The hook by Wiberg is designed to encourage chemists to learn computer programming. It should be particularly helpful to those who wish to take the do-ityourself approach. I t serves as an excellent introduction to the possibilities of computer programming in chemistry. Illustrations are suitably chosen, although the programs are not particularly mphisticated. This is not inappropriate since they are intended to teach principles rather than to serve as production models. A serious programming enthiuiast will need to consult other sourees. Beginning general books such as Organick or McCracken will be useful, (E. I. Organick, "A Fortran Primer," Addison Wesley Publishing Company, Ine. Reading, Mass., 1963; Daniel D. McCracken, "Guide to Fortran Programming," John Wiley & Sons, New York, New York, 1961), and the technical manu& of the computer manufacturers are indispensible for precise definitions of the language t e r m . The coverage in Wiberg's hook was intended to he neither precise nor complete in this d l important aspect of programming. There is a perennial question of obsolescence of programming languages. The statement is often heard that FORTRAN I1 and FAP are obsolete and so is FORTRAN IV. Why, therefore, take the time to learn a dead Language? The question is an important one, and there rue a t least three relevant though not entirely independent answers. First, it is impractical to attempt to use

computer programs without some knowledge of how they are constructed. All programs require the proper (and precisely accurate!) preparation of data cards. If something goes wrong, a bit of programming knowledge may make it possible to proceed. Second, all programming languages work on much the same principles of grammar and syntax. A knowledge of one can make it possihle to understand another. This is true also of the machine languages. Third, there are a good many programs in FORTRAN 11, and these may be around for some time. In order to take advantage of a very important new tool of chemical research it is essential to learn a little programming. Professor Wiberg's book provides a good place to begin. D E L o ~F. DETAR Inslitule of Molecular Biophysics Florida State University Tallahassee

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Journal of Chemical Education

Advanced Physical Chemistry: Molecules, Structure, and Spectra

Jeff C. Davis, JT.,University of South Florida, Tampa. Ronald Press Co., 632 pp. Figs. New York, 1965. x and tables. 16 X 23.5 cm. $12,

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The existence of this hook is based on the premise that the average graduating chemistry major takes the usual introductory course in physical chemistry in which the bulk of the material consists of the "elsssical" topics of thermodynamics, electrochemistry, and chemical kinetics. The more theoretical topics such as quantum mechanics, spectra, and statistical mechanics are either ignored eompletely or, because of the crush of time, dispensed with in a somewhat superficial manner. I t is the purpose of this book "to introduce students in all chemical specializations to the basic ideas and methods of quantum mechanics and statistical mechanics, with particular emphasis on the application of these theories to the investigation of molecular structure." Professor Davis begins his treatment with a brief discussion of the problems of physics that led to the development of quantum mechanics. Of interest here is the formulation of the Lagmngian and Hamiltonian functions in a particularly lucid manner. The principles of quantum mechanics are presented as a series of postulates, definitions, and corollaries that lead to an examination of the important properties of eigenfunctians and symmetry operetors. The entire development is based on Schradinger's treatment in order to avoid the difficulties involved in the handling of matrix algebra. The material in this chapter is potentially difficult because of the whole new set of rules and operations that the student must learn ttnd so the teacher had best discuss it with great care rather than depend upon a perfunctory reading by the student to achieve understanding.

These basic postulates are illustrated by reference to the usual examples of the particle in a box and harmonic oscillator. A digression into energy level8 and statistical mechanics is introduced that cannot be called comprehensive hut it does provide the connection to the equations of classical thermodynamics. The discussion of the hydrogen stom covers over forty pages and is excellent. This is followed by another excellent chapter in which the various approximation methods of solving the many-body problem are presented. Thus, within seven chapters the groundwork has been laid for a consideration of some practical problems of molecular ~rtructure. The remainder of the hook (over 300 pages) is devoted to moleculw spectra in its various manifestztions: microwave, infrared, electronic, and nuclear magnetic. These discussions are far more complete than those given in the usual introductory physical chemistry textbook while at the same time not as comprehensive as one would find in specialized monographs on the subject. Each chapter in the book is followed by a set of problems; in the later chapters they number over 30 for each ohapter and include sample spectra. for interpretation. I t is doubtful if the entire book could be completed in a semester coune an the senior undergraduate level; s. year would he preferred. On the graduate level, it would be an excellent text for firstyear students who have not had any of this material as undergraduates. For higher level graduate students, I would prefer to have the physical chemistry majors take the specialized courses in these subjects using the more advanced texts such Prtuling and Wilson, Ksuzmann, Wilson, Decius and Cross, etc. However, for non-physical chemistry graduate students, Professor Davis' hook used in a semester course would be most beneficial to their understanding of problems in molecular structure that they encounter in their research.

Z. HOFFMAN MORTON Boston University Boston, Mas8achusetts

Phyrico-Chemical Conrtontr of Pure Organic Substances. Volume 2

J . T i m m e m n s , Free University of Brussels. American Elsevier Puhlishine Co.. New York. 1965. viii 4 6 Figs. and' tables. 17 x 24 om. $28.50.

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This is the first supplement to the author's first volume under the same title, published in 1950. The work of authentically compiling numerical data from the literature is one which is unfortunately carried on by too few invcst,igators. I t is fortunate for us that Professor Timmermans has continued active in this important work. The present volume covers, through 1964, the following classes of organic campaonds for which data have become available: hydrocarbons; halogenated hydrocarbons; oxygenated ali-

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BOOK REVIEWS phatic hydrocarbons; oxygenated aromatic hydrocarbons; oxygenated polymethylene hydrorarhuns; heterocyrlic oxygen compounds; s~igars; mixed oxyhalogenated hydrocarbons; nitrogenated aliphatic hydrorarbons; nitrogenated cyclic hydrocarbons; mixed oxygen-nitrogen derivatives of hydrocarborbons; mixed h e b gen-nitrogen derivatives of hydrocarbons: sulfur derivatives of hydrocarbons; derivatives of hydrocarbons wit,h d h e r elements. The reviewer noted that sn incorrect reference in given on page 145 for the viscosity of n-butylcyclopent,ane. The reviewer recommends to Professor Timmermans that in a future volume he give consideration to the following points: (1) Have the publishers arrange to condense the presentation of the data so that ouly about half the number of pages will be required to present the same material; (2) Omit presentation of all data already presented in the tables of the American Petroleum Institute Research Project 44 and the tables of the Manufacturing Chemists Association Research Project, which are available in most of the departments of chemistry in ~miversities throughout the world; (3) Critically appraise the data and with appropriate weighting present selected vslue.9; (4) Where possible, give equations yielding values over the range of the independent variable. Because of the high cost, $28.50, of this volume, it is quite unlikely that ind i v i d ~ d s will want to have s. copy. But each scientific library will probably wish to have a copy for reference by scientists interested in t,hese fields.

FREDERICK D. ROSSINI University of Notre Dame Notre Dame, Indiana

Fundamentals of Carbanion Chemistry Donald J. Cram, University of California, Los Angeles. Academic Press, Inr., New York, 1965. Volume 4 of "Oreanir Chemistrv" series. viii 289bp. Figs. and'tahls. 16 X 23.5 n n . $9.50.

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Most physical organic chemistry texts devote little at,tent,ion to "carbanions"including such relatives as enolate ions and organomet,allic compounds-in spite of the great. synthetic importance of sueh speries. Furthermore, despite extensive treatments of SN reactions a t saturated carbon, SE reactions in which carbanions are potential intermediates are frequently ignored in courses in advanced organic chemistry. This book is intended to help fill the gap. The first chapter is a. compilation of the kinetic and equilibrium acidities of varioux typw of C-H bonds, toget,her wiah a disc,wsiun of the methods of obtaining such data; in Chapter 2 these results are interpreted in structural terms. Chapter 3 is a general discussion of the stereoehemintry of eleetrophilic wbstitu-

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tions and earbanion processes, while Chapter 4 summarizes the detailed studies of Cram and his group on the stereochemical effects of varying the leaving group snd the medium. The fifth chapter deals with the chemistry of allylic anions, involved in base-eatalysed olefin isomerieations, and Chapter 6 concerns miscellaneous moleculm rearrangements in which carhanions are putat,ive intermediates. Among the excellent features of this book are numerous tables, mostly original compilations of hitherto scattered data. Extensive references, and clear critiral discussions of such complex stories as stereochemical retention during deuterium exchange, help the reader to obtain an appreciation of the state of modern research in this field. Furthermore, this is a very personal account in which Cram does not hesitate t o express his own opinions about the interprehtion of some piece of data, even if this interpret,at,ion is a t variance with that of the original author. Unfortunately the original interpretation is sometimes not even presented, and this leads to a lack of balance when questions in active dispute are discussed. The strongest part of the book is that in which Cram's own very important studies are summarised and interpreted. If there is a. flaw, it is that everything is "explained" even when the data are not sufficient, so that open questions tend to be covered up. The printing job is clean and readable, although some of the illustrations are difficult to decipher (e.g., p. 178 B). The unfortunate use of dotted lines instead of single resonance forms can lead students (and even authom, as the "phenanions" on pages 237 and 242 illustrate) into trouble. Except in the illustrations, there are remarkably few errors, either typographicd or factual. Curiously, however, "SE," and "SN," are used throughout instead of the u n t versally accepted " S d " and " S N ~ " ; also, inverse isotope effects are called "negative" effects. I n summary, this is a n important contribution to the chemical literature. While it is perhaps too personal an account to make it a completely satisfactory textbook, it should stimulate research and serve as a useful reference for advanced students, teachers, and chemical investigatoa. RONALDBEESLOW Columbia University New York, N m York

Chemical Energy Laurence E. Strong and Wilrner J. Slmtton, both of Earlham College, Richmond, Indiana. Reinhold Publishing Corp., New York, 1965. Selected Topics in Modern Chemistry. x 115 pp. Figs. and tables. 12.5 X 18.5 em. $1.95.

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Thermodynamics has a. reputation far abstruseness which tends to incnlcate in a beginning student the conviction that he will never be able to understand it.

The omission of the word from the title of this book may be helpful in this respect. More importantly, the development of the subject without the use of the calculus makes possible its comprehension by the average freshman student, who is not a n extinct species (see review by Derek Davenport, J. CREM. EDUC.,43, 56 l19661). Despite its title this little book is a book on thermodynamics, which the authors call "an elegantly logical subject" in their preface. The real concern of the book is "the formulation of the energetics of chemical reaction system?." Some of the general features of energy are pointed out before the discussion is focused on its chemical aspects. This is done in the first chapter, which considers temperature-changing capacity, capacity to produce electricity, capacity to lift masses. caoacitv to oroduce lieht. the interconnection of changes, the concept of energy, and some units of energy. I n the second chapter the authors introduce sueh basic concepts as system, state, adiabatic and isothermal processes, the First Law, internal energy, and enthalpy. The development of chemical energy concepts is then interrupted for brief discussions of calorimetry and the molecular interpretation of internal energy. In the third chspter the authors return ta "the arithmetic of energy" and cansider such topics as thermochemical equations, Hess's Law, enthalpy of formation, and the variation of AH with temperature. The knowledge developed in the preceding chapters is applied in the fourth chapter to selected chemieal systems. Lattice enthalpies and the Born-Haher cycle are discussed, and likewise the calculation of covalent bond enthalpies by analogous energy cycles. The aut,hors show how hydration enthalpies can be calculated from lattice and solution enthalpies, and how the energetics of electrode reactions can be interpreted in t e r m of differences in sublimation enthalpies or hydration enthdpies. The crux of thermadynamies is in the fifth chspter. It is decidedly more abstract than the preceding material, being concerned with "the direction of change." Order and disorder, reversible and irreversible processes, entropy, free energy, the Second Law, all are here. Some of the far-reaching implications of the concepts of entropy and free energy are then considered in the sixth chapter. Here are discussed the free energy of mixing in relation to concentration ratio, the relationship of standard free energy chanee to the eauilibrium constant. the erni it equation; the Third ~ a w , and ' absolute entropies. I n the final chapter the free energy changes that govern the direction of spontaneous change are related to the structures of the reacting substances. I t is pointed out that there are processes for which, essentially, A H = 0 so that AG = -TAS; examples are the mixing of gases and the operation of electrochemical concentration cells. On the other hand, attention is given to equilibrium phase changes, sueh as melting, for which AG =

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