Chemical bonding and structure - Journal of Chemical Education

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observe such items as "temporary" and "permanent" hardness used in reference to soluble calcium salts in water (page 54) in favor of the more modern (updated) terms "carbonate" and "noncarbonrtte" hardness. No mention of electron deficiency accompanies the descriptive ma.terial associated with the hydrides of boron (pages 66-7). The dibasic nature of phosphorous acid (page 114) is not mentioned, although the text covers only NaH2P03 and Na.HPOa. I t is somewhat surprising to see hydrogen presented in considerable detail (Chapter 1) with no mention of heavy hydrogen or deuterium oxide or any comparison of their physical properties with those of hydrogen and water. I n spite of the lack of mention of deuterium or its oxide, one learns that technetium is prepared by "bombardment of molybdenum by deuterons" on page 186. Page 82 contains a reference to the EDTA titration for indium but gives no details regarding the nature of the reaction. Meanwhile no reference is made to the use of EDTA in the coverage of the analytical chemistry of calcium (page 55) or of maenesium (0ap.e 441.

unquestionably compact, but a t the expense of coverage and explication, and the major chapter lacks the logical consistency requisite for a %oberentn treatment. The hook consists of four very unequal chapters-a four page introduction; atomic structure in 30 pages; The Covalent Bond, 63 pages; and 22 pages on ionic bonding. No questions are provided; the last three chapters have several references each, most of which are suitable, but others, such as Ballhausen and Gray (p. 99) are inappropriate-they are designed for graduate or senior students, not first year students. Chapter 4 is probably the most valuable, for it is well written and well balanced between theory and corresponding experimental evidence, with discrepancies also discussed. Valence bond (VB) theory is stressed in Chaoter 3. with a brief

mention is made of alternate approaches: double quartet and tangent sphere models of covalent bonding and crystal field (if not ligand field) model for metal complexes are conspicuous by their absence, especially since all e m be introduced a t least as effectively as VB theory a t this level. A problem in presentation is reflected in the Retrospect (pages 97-8), in which VB and solutions from which nitrogen may be MO theories are compared. Few students prepared in the laboratory. I n the reacwill appreciate the comparison, for want tion of alkali and alkaline earth metals of understanding of either, and these may with liquid ammonia (page 111) the reader well question the author's emphasis on is led to believe that the displacement reVB theory. The instructor should also actions and preparation of t,he amide salts question the argument, for while it may of these element3 proceeds rapidly. No be true in general that "we cannot say mention is made of the use of catalytic that one tbeory is 'rigbt' and the other materials to enhance these reactions. The 'wrong'," certain aspects of conventional blue colored solutions of the alkali or VB presentation me inconsistent with dksline earth metals in ammonia are not experimental evidence. The concept of mentioned. "bond dipole moments" ignores the imThis supplemental book fills a need portant-if not dominant-role of lone which has been evident far some years in pairs in determining molecular dipoles our general chemistry program. The ini(compare, e.g., NH1 and NFI). The tial effort in any specific departure from related question of "ionic" and "covalent" an accepted procedure often leads to quesstructures for HC1 (p. 80) implies a t tions and disagreement regarding certain least a different electronic arrangement aspects of the presentation. I t is hoped for the two representations; this is a perthat revisions of this work will include sistent fiction, for the same electronic further uodatinr of contents. alone with arrangement could represent either soimproved clarification, explanation, and called "structure." simplification of many topics. Many terms are introduced without G. NICHOLSON adequate explanation (or justification). DOUGLAS Easl Tennessee State Uniuersily For example: with reference to bonding Johnson Cily in SO2, a vacant 3d orbital is described as having "the rigbt symmetry" (page 78); "group theory," "symmetry point group" and other procedures "beyond the Chemical Bonding and Structure scope of this book" are offered without explanation; AH is first found on page 39, Ernest Griswold, University of Kansas, without definition; and an extraordinary Lawrence. Raytheon Education Co., footnote on page 11 presumes that wave 124 Indianapolis, Indiana, 1968. iv functions are already part of the student's pp. Figs. and tables. 13.5 X 21 cm. vocabulary, for EYI, VYI, and V2YI all 81.95 paper. appear ( v is "explained" as "a. differential This monograph is anotber entry in operator from calculus"). Other unanotber series ("Topics in Modern Chemdesirable features include diagrams (page istry") of supplementary materials for a 64) showing lines connecting non-bonded general chemistry course. The author rather than banded atoms; questionable states in the Preface that "the principal energy level assignments in MO diagrams purpose of this book is to provide. . . s. and loss of the coefficient for YII, on page compact and coherent introduction to 90. The discussion of covalent bonding current views of chemical bonding and before ionic bonding is another apparent molecular structure as related to the limitation. I n the paragraph on How electronic structure of the atom." It is Covalent Bonding Occurs (page 51) we

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find the forceful statement that only Conlombic forces are responsible for bondine. but not until Chaoter 4 is the Inw prr.-enwd (pngr 113,-and the earlier srnrmmnt promplly ignored. Ilm%ever, hinrlmg of the b w k is nucll that nfter two or three uses the section on theory of lattice energy (pages 113-118) was more readily available-it fell out. Returning to the Preface, we find, "In gaining acquaintance with important experimentally determined properties of bonds and witb theoretical interpretations that have been proposed, the reader acquires a feeling for the utility and significance of these concepts in chemistry. ." This reviewer would agree with respect to the experimental properties, hut the question is whether that "feeling" will be-about the theorv-one of understand-

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chemistry by emphasizing theory for which adequate groundwork has not been laid. Will the surviving students be better chemists? That, perhsps, is a question to which we should address ourselves before continuing the practice of distorting quantum mechanics for minds of beginning students-and probably vice uersa. LAWRENCE J. SACKS Harnpton Institute, Harnpton, Virginia $5588

Bonding and Structure: A Review of Fundamental Chemistry Emil J. Margolis, the City College of the City University of New York. Appleton-Century-Crofts (a division of Meredith Corp.), New York, 1968. vii 175 pp. Figs. and tables. $3.50, paperbound.

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This paperback was designed as a supplement to the general chemistry text. One chapter is devoted to the electronic structures of atoms and to related atomic or elementalproperties. Another considers properties of the chemical bond, including deeree of ionic character. bond strenrth. bond length, dipole moment, and bind orientation. The third chapter deals witb transition metal complexes, treating nomenclature, coordination number, types of isomerism, and applications of crystal field and valence bond theory. A final chapter describes molecular orbital theory, applying it to diatomic molecules and, briefly, to transition metal complexes. About fifteen questions follow each chapter. Each question is answered in detail in a n appendix. The treatment of transition metal complexes and the crystal field theory goes well beyond the customary level in freshman texts. However, a comparison with several texts that might be used in freshman chemistry courses giving emphasis to structure and bonding shows that for the other topics considered this paperback presents little or no additional material. The book cannot be recommended for self-study because of the shortage of (Continued on page $80) Volume 46, Number 4, April 1969

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