Bond energies, ionization potentials, and electron affinities

don's, Cotrell's, and Franklin and Field's, without comment. A brief preface of about 26 pages summarizes quite well the common experimental technique...
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BOOK REVIEWS explanation or expect,ation of the effect of electrolyte composition on cell emf's. Also distressingly absent is any serious discussion of the problem of junction patentials in concentration cells with transference, although the thooretical eonsiderations necessary for such a discussion have been well worked out. With the exception of a few tables, fused salt scientists will prohahly discover little that is particularly useful to them in this first chapter, and those seeking an introduetion to the subject are advised to look elsewhere (Laity's chapter in Jane and Ives, "Reference Electrodes," Blander, "Molten Salt Chemistry," or Sundheim, "Fused Salts"). The remaining three chapters are devoted primarily to the practical aspects of the construction of reversible halogen, oxygen, and metal-metal ion electrodes for fused salt media. The literature coverqe appears to he fairly complete, and the detailed description and numerous illustrations could make the second half of the book of considerable utility to those who are concerned with techniques of electrode fabrication. As with the first chapter, however, the theoretical discus; sion of electrode performance is uneritied and leaves a great deal to he desired. In view of the specialized nature of this hook, its unsatisfactory treatment of many detaile, and the fact that it is nearly four years out of date in a rapidly advanc-

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Journol o f Chemical Edvcofion

ing area of science, potential buyers are advised by this reviewer to consider their needs carefully before purchasing it.

from earlier compilations, such as Gaydon's, Cotrell's, and Franklin and Field's, without comment. A brief preface of about 26 pages summarizes quite well the CORNELIUS T. MOYNIHAN common experimental techniques and California Slate College their shortcomings. Lo8 Alzgele~ There is little attempt to deal critically with the data. and only occasionally do the authors state what they feel to be a most "reliable" or "preferred" value. Thus, Bond Energies, lonizotim Potentials, the reader will find the C-H hond dissociand Electron Affinities ationenergyof 12-C4HsHlisted as94 kcal/ V . I . Vedeneyev, el al. Translated by mole (from pyrolysis), 101 & 2 (electron Seripta Techniea, Ltd. St. Martin's impact), and -105 (photoionization). A Press, New York, 1966. xiv 202 pp. rather complex discussion in fine print sugTables. 15.5 X 23.5 ern. $8.50. gests that 94 is most likely. These can be compared with a "best" recent value of This book is a compilation of all of the 97.8 kcal/mole. Another example is the data available to early 1962 on the gas N-N bond in F2F-NF* for which three phase heats of formation of organic and in30 =t7 values are given in Table 2: organic radicals, cations, and anions. The (electron impact); 19.8 f 8 (equilibrium data are presented in a series of twelve dissociation); and 53 (electron impact), tables, each of which give relevant data in which they prefer. The "correct" value of the form of hond dissociation energies at 20 =t2 is to be found in their second quoted 0% and/or some higher temperature, the reference, while Table 3 quotes 21 f. 1 as literature source, and some explanatory the preferred value. notes. The first three tahles give dissociaWhile some attempt has been made to be tion energies for: (1) Diatomic Mole consistent in the various tables, it is by no cules, (2) Organic Molecules and Radicals, means uniform. Table 3 gives DHo (HOa and (3) Inorganic Molecules and Radicals. - H ) = 88.6 2, which permits us to calTahles 4 through 6 give Heats of Forms, culate AILD (HO4 = +4.0. However, tion for Atoms; Organic Radicals and Table 5 lists two values for AHr' (Hog): Inorganic Radicals. Tahles 7 through 12 4 + 3, and a "preferred" value of - 5.3 give ionization potentials for all these 3! Not a few quoted values of heats of categories, while the final short Tahles 13 formation of both radicals and molecules and 14 present the few electron affinities differ appreciably from current vdues. and proton afinities, which are availahle This, however, is a consequence of the by measurement or estimate. much of the data is merely rerecorded (Continued on page

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BOOK REVIEWS rapidly changiug statc of the art, rather than careless selection. In general, the bond dissociation energies q ~ ~ o t e for d organic molec~~les tend to dcviate appreciably from values published in the last foor yean. This compilation can be quite useful as a bibliographic source for bond dissociation energies and ionization patentids in that i t carries somewhat more carefd earlier compilat,ions, such a5 that b y Franklin and Field, up to 1962. However, it is not s book for the beginner to use in cavalier fashion, or from which other compilers can make glib qoatations. SIDNEYW. BENSON Slanjord Research Institute Men10 Park, California

Basic Electronics for Scientists

James J. Brophy, Illinois Institute of Technology Research Institnte, Chicago. McGraw-Hill Book Co., New York, 1966. xiii 471 pp. Figs. and tables. 16.5 X 24.5 em. $9.50.

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There are perhaps half-%dozen texts which are directed to the education in eketronics of students of physical sciences. Nexrlv $1 of these texts have a o o e a ~ din involved in electronic pmblems only recently. The present trends of d l branches of science certainly suggest t,hat students of these disciplines make edueational contact with some aspects of elmtronies a t the undergraduate (or high school) level. Scientists' needs in electronic education are impossible to predict; it is reasonably safe to say that some is necessary just to select instruments and read instruction manuals. A physical scientist experienced in electronics would probably organize and teach this subject in an operational manner, presenting information as it may relate to a specific measurement problem or instrument. An electrical engineer would see tho need for teaching a core of basic information followed by as many xpplications as time or space permits. Author Brophy presents bssic electronics, and a lot of it, compared to other texts of t,ha type. Each topic is treated in depth, e.g., Ohm's law is derived from definitions of current and electron mobility. Passive

freqoency dependence of the rktio of o u e put to input voltages are used only occasionally although the necessary eqnations are usually derived. Bases of operation of vacuum tube and transiston are discussed in separate c h a p ters along with elementary circuits. The diagrams used to explain the operation of transistors, and other solid state devices in later chapters, are particularly good. Equivalent circuits and hybrid parameters are introduced in e d y chapters and used

(Cmlinued m page Ad54)

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