Chemical Principles in Calculations of Ionic Equilibria: Solution Theory

Principles of Analytical Chemistry. Charles A. Reynolds, University of. Kansas, Lawrence. AUyn and Bacon,. Inc., Boston, 1966. xi + 288 pp. Figs. and ...
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Principles of Analytical Chemistry

Charles A. Reynolds, University of Kansas, Lawrence. AUyn and Bacon, 288 pp. Inc., Boston, 1966. xi Figs. and tables. 15 X 23 cm. $5.95.

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In the preface the author points out that descriptive laboretory exercises in many general chemistry (firsbyear college or university chemistry) courses ". are being supplanted by experiments which require exact measurements!' He goes on to say "Recently published textbooks desiened for the first-vear course show little cksnge in the Gverage of material which would prepare the student for these experiments." His first and presumably his major objective in writing this book is stated in the preface as follows: "This book was written to meet the need for a supplementary freshman texrbook which will help the student understand t,he quantitative work which he will be doing in the lahorrttory." The inclusion of a 288page supplementary freshman textbook in addition to the usual 650-page textbook and a typical 3Wpage laboratory manual would seem to place quite a burden on the student during his often critical first year of college or university work. The author's second objective in writing this book is: "This book is also designed to meet the needs of a one-semester course in analytical chemistry or quantitat,ive analysis; in fact, it is based to some extent on the lectures given by the author in such a course. Additional laborittory material, which was changed each semester, was also given to the students in this course." As opposed to most textbooks on elementary quantitative analysis, this one does not include a discussion of the theory or use of the analytical balance. The student presumably is to learn all he needs to know about the most basic and most accurate operation in quantitative analysis from a laboratory experiment for which he has had no advance preparation. This book is composed of 18 chapters on the following topics: Chapter 1. The Realm of Analytical Chemistry (6 pages). This chapter is well written and is quite satisfactory for eit,her of the intended uses far which the textbook was written. Chapter 2. Treatment of Analytical Dst,a (12 pages, 6 examples, 8 problems). Adequate coverage for either freshman or sophomore students. Chapter 3. Fundamental Chemical Principles (7 pages, 3 examples). Coverage of this subject is comparable to that included in almost any textbook for elementary quant,itative analysis. The inclusion of problems in this chapter would be of great help to students being introduced to such concepts as activity and ionic strength for the first time. Chapter 4. Titrimetric Methods of Analysis (6 pages). This chapter is a very brief introduction to the subject and includes definitions of such terms as standard solution, titration, primary and secondary standards, end pomt, and indicator blank. Chapter 5. Acid-Base Stoichiometry (12 pages, 12 examples, 4 questions, 35

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problems). Coverage quite sat,isfactory and the examples, questions and problems are well chosen. Chapter 6. Acid-Base Equilibria (29 pages, 23 examples, 11 questions, 17 problems). This chapter is excellent for a course in quantitative analysis. However, the chapter includes much more material than could be effectively used in a general chemistry course. Some topics are included which are often discussed in graduate courses in quantitative analysis. Chapter 7. Acid-Base Titrations (24 pages, 5 examples, 10 questions, 14 problem). This chapter is well suited far a course in elementary quantitative analysis. Mare detail is included than is likely to be mastered by students taking generd chemistry. Chapter 8. PrecipitrutionTitrations (16 pages, 5 examples, 9 problems). This is a standard treatment of the subject and could be used a t either the freshman or sophomore level. Chapter 9. Complex-Format,ion Equilibria (21 pages, 5 examples, 10 problems). Excellent treatment of the subject and should be h e for a, course in elementary quantitative analysis but is much more involved than most instructors would want to present in general chemistry. Chapter 10. Oxidation-Reduction Stoichiometry and Equilibria. (27 pages, 17 examples, 20 problems). Oxidation potentials are used throughout this chapter bat it is pointed out on page 150 that ". . many chemists prefer the use of t,he reduction half-potential convention ss opposed to the half-reaction potential convention." This chapter represents a standard treatment of the subject s t the sophomore level. Chapter 11. Redox Titrations (10 pages, 2 examples, 7 problems). Cunventional discussion a t the sophomore level. Chapter 12. Potentiometric Titrations (13 pages, 1 example, 4 problems). The instructor in elementary quantitative analysis would very likely want to s u p plement the material in this chapter with mare detail. Parts of the chapter vould he of help to freshmen. Chapter 13. Gravimetric Analysis (6 pages, 5 examples, 12 problems). Primarily s. discussion of the gravimetric conversion factor. Example 13.2 has a in the misprint-x should replace first equation. Chapter 14. Solubility and Purity of Precipitates (16 pages, 12 examples, 12 problems). Discussion is quite satisfactory for elementary quantitative analysis but contains material not normally taught in general chemistry, e.g., the bheory of occlusion by solid solution forms, tion. Chapter 15. Sepsrrstion by Precipitation (14 pages, 1 example, 8 problems). The material in this chapter, if supplemented by additional lecture material would he fine for a course in quantitative analysis. I t is doubtful that this chapter would be of much help to freshmen. Chapter 16. Sepmbion by Electrolysis (16 pages, 3 examples, 10 problems). Satisfactory for either freshmen or sophomores.

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Chapter 17. Separstiou by Estraction, Ion Exchange and Chromnlugraphy (9 pages). This chapter discusses briefly the theory of extraction. Hardly any descriptive material is included and aft,er reading the chapter, the student would know very little about practical applications of the separation techniques. Chapter 18. Spectmphotometric Aualysis (13 pages, 8 problems). The principles are discussed but no applicaliana are mentioned. The topics discussed in this textbook are given rather inconsistent coverage, some being quite brief while others include material suitable for and often included in graduate courses in qoantitative analysis. Writing a. book which would allow the author to achieve both of his stated objectives would, indeed, seem to be a most difficult task. In his effort to achieve these objectives, it would seem that the author has been farced to make campromises which have resulted in a book that comes close to attaining the first objective but perhaps falls a hit short of the second objective. Thhse teaching a course in general chemist,ry which includes laboratory experiments that require exact quantitative measurements, will find this book quite useful as a supplementary textbook. This textbook could also be used for a survey course in elementary quantitative analysis, but the instructor might very well want to present s u p plementary lecture material on certain topics and also include a discussion of practical applications of the principles studied.

V. BANKS CHARLES Iowa State Zrniuersilg Ames

Chemical Principles in Calculations of Ionic Equilibria: Solution Theory for General Chemistry, Qualitative Analysis, and Quantitative Analysis

Emzl J. Margolis, City College of New York. Macmillan Co.. Inc.. Sew York. 482 pp. '~igs.'and tables: 1966. xi 16 X 24 em. Paperbound, $3.95. Cloth, $7.95.

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In this treatment of the principles of ionic equilibria in aqueous solution, the author hits attempted to design a book suitable for the average student to use as a supplement to the general chemistry text, as a self-contained basic text for qunlitative analysis, or as a. supplementmy text for quantitative analysis. The primary emphasis is on homogeneous phase equilibria, heterogeneous phase equilibria, and "reactant potential" and free energy. Each major section includes a discussion of principles, 20 to 30 "inteipretntive exercises" worked out in minute detail, and nearly 100 "supplementary assignments!' While the author's basic concept of the book is good and the format is attractive, I feel that it is of littlevalue as a text, as it is generally confusing,frequently misleading, and often conceptudy unsound. The author's style is wordy, indirect, and repetitious. The book is designed so (Continued on page AlOS6)

that very little challenge is left to the student. Mathematical details as, for example, the various steps in thesolution of a quadratic equation are included at every opportunity. There are so many illustrative examples that there is often little variation from one to the next. The problems merely echo the calculations considered in the examples. The anthor wants the student to rediliae that the solution to a problem requires an awareness of the kind of data required and to this end he has included a good compendium of equilibrium data, hut in spite of this most of the problems contain all necessary data. He deplores the "plug-in" type of prahlem, but any required equations we made readily available to the student. For example, after deriving equationsfor (H+), (OH-), and the degree of hydrolysis in a solution of sodiwn acetate, he presents the corresponding equations for t,he hydrolysis of ammonium chloride. Perhaps the apparent shortcomings of this book as discussed in the preceding paragraph merely reflect certain pedagogical prejudices of this reviewer. However, in the following paragraphs examples will be cited in which I feel that the author is guilty of serious omissions or of grave conceptual errors. The author bas ignored the concepts of charge and material balance and therefore many kinds of equilibrium problems have not been considered or have been treated incorrectly. Far example, there is no discussion of very dilute solutions of strong or weak acids and the treatment of palyprotie acids is almost entirely incorrect. On page 63 he calculates the pH in a solution of HC08- by considering only ionization and this leads him to conclude that HCOI- is a good "one component buffer" for OH-. On Daee 116 he concludes that the following equations are valid for a solution of HAsO12-. (HaOt) = ( A s O F ) - (HASO,-) (OH-) = (H,AsO,-) - (AsOda-) Thr ..wmcl rqtwrim VHU be dvrivrd dtwvrd fmm rtr "prt ton r.,ndiriox~" e.lu%tion,and this t k al,wnl rtmclt~iionthxt 1110' Imd; must be negative. The author occa~ionslly forgets that there is one and only one concentration for each species in a given solution and that this wmcentration must satisfy all equilibrium expressiom. On page 80 he calculates the concentration of ammonia in a solution of Ag(NH3).+ by adding together the concentrations obtained by considering separately each of the stepwise dissociation reactions of the complex ion. On page 112 he ignores the presence of NHbOAc in s. mixture of NH40AcandHOAc, calculating the pH from the concentration of HOAo alone since he contends that the NH4+and the OAc- are "paired" and thus "have already been removed from the mathematical 'scene.' " The author's discussion of the "American" and "European customs" for electrode potentials is unnecessary and confusing, and has no place in a modern elementary text. The convention adopted by the IUPAC in Stockholm in 1953should be followed and all potential data should be given as reduction potentials. There are only 4 figures in the entire book and I feel that the concepts of equilibrium systems, particularly poly-

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protic acid and complex ion systems, can be made much clearer by the presentation of data in graphical form. I t would also seem reasonable that any modern treatment of equilibrium should include some discussion of the use of logaithmic concentration diagrams for the solution of equilibrium problems. ROYA. WHITEKER Hawey Mudd College Claremonl, California

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Chemistrv in Nonaaueous lonizina ~olvents.' Volume i,Pati 1, Chemistry in Anhydrous Liquid Ammonia

Jaehen Jander. Interscience Publishers ( a division of John Wiley and Sons, Inc.), New York, 1966. xxiv 561 pp. Figs. and tables. 17 X 25 em. $27.50.

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For several yea18 publishers and colleagues have urged this reviewer to write a comprehensivetreatise on the physical and inorganic chemistry of liquid ammonia. solutions. Fortunately, this is no longer to be considered since the present volume meets the admittedly existing needs admirably. This is Part 1 of Volume 1 of a series of monographs ooncerned with "Chemistry in Nonaqueous Ionizing Solvents;" Part 2 of Volume 1 was published earlier and covers organic resetions in liquid ammonia. The original editors of this series were the late Professor Dr. Gerhart Jander and Professor Dr. Hans Spandau. Upon the death of Professor Jmder, Dr. C. C. Addison became a coeditor. After a brief introductory section (4 pages) dealing with the preparation, purification, and handling of liquid ammonia, about 30 pages are devoted to a discussion of physicsl properties of ammonia. Although this section could have been much expanded, the present treae ment provides both adequate orientation and entre to the literature. The longest part of the book, some 430 pages, is concerned with essentially d l of the important aspects of solutions of inorganic substances in liquid ammonia; examples include vapor pressure data, molecular weight determinations, solubility relationships, electrode ~otentials, polarography, and thermochemistry. Particularly noteworthy is the section dealing with solutions of metals in ammonia. This includes both a concise review of the relevant physicochemical measurements that have been made and a thorough review of the various models that have been proposed to account for these physical properties. Almost equally useful are the sections on scid-base relationships and oxidation-reduction processes. The third motion covers the more recent literature, follows the same kind of subject matter organization, and is apparently an addendum. Among the outstanding features of this monograph rue: (1) The extent to which the authors have achieved conciseness without either loss of clarity or omission of important information. (2) The thoroughness with which the various sections are documented. (3) The extensive inclusion of equipment diagrams-

albeit not always the best ones-and graphical representations of data. (4) The extensive recourse to data. tabulation which makes the book especially useful for reference. Seldom is one able to write about a book with so much enthusiasm; it is tndy an ouktanding contribution to the chemicalliterature. In its field, this volume will be the standard reference work far many years. Errors are few, and they are of a nature (mostly typesetting) that does not lead to misunderstanding. The price of the book ($27.50) is discouraging--even in Texas where everyone has money except the poor folks. Finally, in the English language version of the Preface, this reviewer was successively surprised and concerned to learn that "reference must be made to the collections of WATT, which have survived for over a. century!' The Univer$ityof ~ e z a i Austin Leetures on Manar ond Equilibrium

Terrell L. Hill, University of Oregon, Eugene. W. A. Benjamin, Inc., New 306 pp. Figs. and York, 1966. xi tables. 16 X 23.5 em. Clothbound, $9; paperbound, $3.95.

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"This book is intended primarily as a supplement to part of a freshman honors course in chemistry. .the book could also serve as collateral reading in a. physicad chemistry course!' The topics covered include states of matter, intermolecular forces, thermodyn~mics, kinetic theory, solutions, and chemical equilibrium. The book is clearly written, but very concise; it is the kind of supplementary reading that requires very close attention. The treatment is authoritative, as is to be expected from this author who has written advanced texts on statistical thermodjrnamics and many research papers on the chemical applioations of statistical mechanics. Many topics are discussed which are not u a d l y included in even high level general chemistry texts or even in some physical chemistry texts. Some examples are the Lennsrd-Jones potential, the theoretical calculstion of the second virial coefficient, radial distribution fmxtions, quantum theory of specific heats, the statistical interpretation of entropy, chemical potenti& and the application of the GibbsDuhem equation to non-ideal solutions. In most eases the results are derived from fundamental principles, though in some the final r%.sultsare merely stated. This book can be recommended as a source of supplementary assignments to highly motivated able freshman or as supplementary material in a physical chemistry oourse. Even if not assigned to students. it will be useful to chemistry teaehersas a source of new ways to aupraach some important topics in the chemical curriculum. ROBERTROSENBERG Lawrence University Appleta, Wisconsin

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