NEW BOOKS years to the nebulous area in the curriculum between general chemistry and "modern" analytical chemistry. Presently there is not enough time to cover chemical calculations in depth in general chemistry and most analytical courses stress instrumental techniques. In the reviewer's opinion, this book is best suited as a text for an independent, one-semester course on ionic equilibria and solution chemistry for chemistry majors in their second or third semester. This would have the additional advantage that general chemistry could become somewhat more descriptive than the present quantitatively-oriented course which often loses students in a maze of derivations, equations, and calculations. The first two chapters are primarily a review of mathematical operations and chemical definitions and might better have been summarized in an appendix. Errors noted in this text were minimal. In working representative samples of the problems, no calculation errors were found. However, in the descriptive sections several points deserve comment. On page 52, the term "pseudo-salt" is applied to mercuric chloride to indicate its covalent nature. I doubt a need exists to coin new and ambiguous terms to describe an extreme in the continuous gradation that occurs in bond covalency. It gives the impression that there are such things as 100% ionic bonds. On page 293, the author perpetuates the error of the mechanism by which the glass electrode functions. Although its mode of operation is not completely understood, it is now generally accepted that hydrogen ion diffusion through the glass membrane does not occur, but rather it is an ion exchange process in which hydrogen ions from the solution exchange with alkali metal ions in the surface layer of the glass. The potential difference that develops on the external surface of the glass is thereby dependent on the hydrogen ion activity in the solution. Finally, on page 318, I question the statement that metallic sodium forms at the mercury cathode instead of hydrogen gas even in an acid solution. The book contains a very good selection of worked problems totaling about 100 and an abundance of over 200 supplementary problems representing virtually all facets of the material discussed. The most notable exception is in the section on redox titrations where the description of this type of calculation is quite good, but there is practically nothing about them in the interpretive exercises and problem section. In most cases the worked problems are clearly explained in a logical, stepwise manner.
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Circle No. 59 on Readers' Service Card V O L . 3 8 , N O . 1 3 , DECEMBER
1966
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75 A
