Principles of chemical equilibrium (Morris, Kelso B.) - Journal of

Principles of chemical equilibrium (Morris, Kelso B.) Lawrence P. Eblin. J. Chem. Educ. , 1966, 43 (2), p 110. DOI: 10.1021/ed043p110.1. Publication D...
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The t h i i chapter, Ionic Chemical Equilibrium, constitutes more than half the book. Special attention is given to the equilibria of qualitative analysis. Topics that are considered include the determination and use of ionization constants, common ion eKect, solubility product, pH, hydrolysis, the classical scheme of qualitative analysis for cations by groups, buffers, fractional precipiMODDIED. TAYLOR tation, and dissolving precipitates. ReHoward University grettable features of this chapter are Washington, D.C. the absence of Brmsted terminology and the complete omission of amphoterism. There are unnecessary digressions to present IUPAC rules for naming complex ions and to discuss standard solutions and titration calculations. I t is disPrinciples of Chemical Equilibrium appointing to come upon the following statement on page 87: "Titration calcuKelso B. Morris, Howard University, lations are facilitated greatly by employWashington, D. C. Reinhold Puhlishing the concept of epuiualnls.. . ." In ing Co., New York, 1965. Selected one of the early volumes of this series, Topics in Modern Chemistry. xi 114 "The Mole Concept in Chemistry," a pp. Figs. and tddes. 13 X 19 em. good case was made for dispensing with Paperbound. 51.95. equivalents and normality. Equally disturbing is the expression "change in This book is another in the Reinhald valence" on page 88. series of paperbacks intended to serve as There are several items in this book that supplements to general chemistry textare indicative of careless editing. On page books. It consists of three chapters. 24 it is stated that nitrogen will react with The first chapter, entitled Heterogeneous hydrogen a t 25°C. On page 33 it is Equilibrium and the Phase Rule, presents stated that AS is a measure of the ranthe phase rule equation and the Clapeyrondomness of a system. According to a Clausius equation without derivation. It statement made on page 40 a. catalyst can includes the phase diagram for water, a be either an accelerator or an inhibitor. simple eutectic diagram, cooling curves, a On pages 57 and 59 the formula weight of a phase diagram for a pair of substances salt is referred to as its molecular weight. forming three compounds, and the vapor On page 58 it is stated that for each mole pressure-composition diagram for the of Bi& that dissolves two Bia+ ions and hydrates of CuS04. The discussion covers three Sa-ions are formed. incongruent melting, solid solutions, and the distribution of a solid between two LAWRENCE P. EBLIN immiscible liquids. The presentation of Ohio University equations without derivation is a frustratAthas ing tttetic, but at least there is material in this chapter that is not present in most general chemistry texts. The second chapter is entitled NanElements of Inorganic Chemistry ionic Chemical Equilibrium. The expression for the equilibrium constant is Robert A. Plane, and Ronald E. Hester, derived by equating rate expressions for Cornell University, Ithaca, New York. the forward and reverse reactions. No W. A. Benjamin, Inc., New York, mention is made of the fact that rate 1965. Physical Inorganic Chemistry expressions hased on chemical equations 188 pp. Figs. and Series. xiv are usudly false. In this chapter the tables. 16 X 23 om. Clothbound equation relating KOand K, is derived! $8; paperbound, $3.95. As the thermodynamic interpretation of This modest volume with a somewhat the equilibrium constant is approached, it ambiguous title is one of the two introcomes as a shock to see free energy (the ductory books in a series which is intended Gibbs function) represented by the symbol as a treatise on Inorganic Chemistry. F instead of G. The Principle of Le According to the authors, Tlements of Chatelier is the basis far a discussion of the Inorganic Chemistry" is for use with separate effects of temperature, concen"Physical Inorganic Chemistry," by tration, pressure, and inert material on Sienko and Plane. as a text in a oneterm chemical equilibria; the inability of a catalyst to shift the point of equilibrium is properly emphasized. This is material that is contained in any general chemistry volumes would serve as a. satisfactory text textbook that is likely to be used in a for more advanced courses. course for which paperback supplements The authors have faced the difficult are appropriate. The effect of temperaproblem of selectionof descriptive material ture changes upon the equilibrium conby taking the current interest in various stant is the topic for a discussion hased areas as an indication of their importance. on the van't Hoff equation and the Many of the subjects so selected are given Kirchoff equation. Neither of these equarather sparse treatment. Indeed none tions is derived, but a diagram (Fig. 2-2) receives su5ciently detailed discussion is provided that has pedagogical merit for to he valuable to the reader except pershowing the variation of equilibrium canhaps to to it to his attention that work stants and free energies of reactions with has been done in the area. In both temperature. of gram molecular weight might cause some confusion. One has the feeling that it would be much better for the teacher to design his o m problems as the need arose. Since this will not he possible until teachers are better trained, such books as "General Chemistry Workbook" fill a useful role in chemical education.

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volumes, the four and a half pages d e voted to boron hydrides, including the figures, give a very inadequate exposure to the subject. One would of necessity go to the special volume in the series for information on this topic. The chemistry of oxygen compounds of the heavy transition metals including complex oxides, isu and heteropoly acids, and bronees is given in one paragraph. The series does not yet contain a volume to supplement this deficiency. A list of suggested supplementary reading is given at the end of each chapter. I t includes a variety of monographs, special chapters in various compendia including Gmelin, usually without reference to specific topics. A brief statement describing the reference is, however, given. A. F. Wells, "Structurd Inorganic Chemistry," for example, is listed several times-"Structure of solid compounda clearly described'' (p. 21); "Structures of solid compounds" (p. 31, 52, 66). A few old favorites are listed-Yost and Russell, "Systematic Inorganic Chemistry" (1944), -"a detailed account of many aspects of this group chemistry (v) particularly good on reaction kinetic8 and mechanism" (p. 135); "remains a useful classic" (p. 153). 0. K. Rice, "Electronic Structure" (1940t"an excellent hook in all ways" (P.21). The authors claim to systematize d e scriptive behavior in terms of currently used theories. Beoause of the highly condensed nature of the text, the explan* tions are not always fully developed and occasionally meaningless statements are found. The anomaly of the ionization of first row transition elements losing 4 a electrons whereas in the Aufbau scheme the 4 s level is placed below the 3 d is rstionalized by saying that "the reason for this rather unexpected hehavior must lie in the different potential experienced by the electrons in the two cases." We find elsewhere the statement: "Based on, or in some cases, in spite of, the data. which exists it seems that all actinide ions have a radon shell of 86 electrons plus only 5 f electrons!' A few misprints are found, some mi* information is given; and there are some contradictory statements: "PbOfissentially basic" (p. 102); "PhO~principally acidic" (p. 112). "SnCl-covalent liquid" (p. 112); "SnCbionic solid" (p. 157). "PboO, considered as plumbous orthoplumbate." "PbsOi behaves as plumbous metaplumbate!' Does the student know how an orthoplumbate should be considered or how a. metaplumbate behaves? The general treatment leans heavily toward reaction mechanism. Methods of preparation me intentionally omitted because the student has presumably learned all that is necessary in more elementary courses. The hook could serve ss rtn outline of topios which could be covered in a course. The student would probably have to rely on lecture notes or supplementary reading sourcesfor study. No examination questions are offered. The index is not extensive. I t is a pity that the editors of the series could not have arranged a merger of (Continued on page A18O)