Book reviews - Chemical principles in calculations of lonic equilibria

Sep 21, 2008 - Book reviews - Chemical principles in calculations of lonic equilibria. Richard A. Durst. Anal. Chem. , 1966, 38 (13), pp 74A–76A. DO...
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NEW BOOK§ est to the laboratory worker, and he has succeeded admirably. The reviewer regards this as the most useful book on the subject that he has yet read. Progress in Nuclear Energy. Series IX, Analytical Chemisfry. V d . 5. instrument a n d Chemicai Analysis Aspect5 of Electron Mi'croanalysis a n d Macroanalysis.

Herbert A . Elion. ix + 256 pages. Pergainon Press, Inc. 44-01, 2lst St., Long Island City, N . Y . 11101. 1966. $14.

Reciewed b y L . S. Birks, U . s. Naval Research Laboratory, Washington, D , C . 20390. I t is only about 15 years since the beginning of elect'ron probe ana,lysis but' the subject, has attmcted grea,t att'ention because of the instrument's unique ability to perform quant'itative chemical analyzis on seleckd, micron-sized local areas in alloys, minerals, biologicak, etc. Many papers a n d several books have been published outlining principles and practice. The most re-

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ANALYTICAL CHEMISTRY

cent of these is the book by H. A. Elion. The book starts with an introductory chapter on $istorical background which emphasizes the roles of the corporations with which the author has been connected. This is followed by chapters on electron optics, x-ray crystal optics, detectors, specimen preparation, factors in quantitative analysis, and miscellaiieous related topics. Chapter headings notwithstanding the reader finds that the book is clearly divided into two distinct areas, namely a detailed dispqsion of electron optics which takes u p 30% of the book followed by a general, descriptive coverage of the rest of the subject. TYithin the area ofLelectronoptics, D r . Elion takes. a somewhat low position on the merits of afocal electron lenses but unfortunately does not give any quantitative 1-alues for their aberrations compared with usual electron lenses. Other researchers more versed in electron optics than this reviewer have stated in the past that the theoretical ad\-antages ascribed by Elion to afocal lenses do not exi-t in practice. In addition, most analysts have n o control over the electron optips design of instruments : thus the lengthly discussion is largely wasted on them. Contrasted nith the overly long section on electron optics, many of the topics on which the analyst, especially the relative newomer, needs specific guidance, are covered in a very cursory fashion or only by references to the literature. For instance, there is no discussion on precision or accuracy (they are not even listed in the index) : there are only three sentences on the important shift of pulse amplitude x i t h counting rate for proportional detectors : procedures for converting meaeured x-ray intensity t o chemical composition (quantitative aiialysis) are discussed so briefly that the analyst has no equations t o actual13 use. In favor of the book, it should be said that, except for the electron optic,c 2.ection, the material is very readable. Also the bibliography is extensive and seems quite complete. Chemical Principles in Calculations of Ionic Equilibria. E n d J . A l a r -

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golis. zi 482 pages. The ~Tfacnaillan Co., 60 Fifth Ave., iYew Y o r k , N.Y . 10011. 1966. $7.95. ( P a p e r back : 83.95).

Reviewed by Richard A. Durst, Department of Chemistry, Boston College, Chestnut Hill, Mass. 02167. The material presented in this text is n-ithout doubt very important in the ouwall education of a chemist, but unfortunately has been relegated in recent

NEW BOOKS years to the nebulous area in the curriculum between general chemistry and ”modern” analytical chemistry. Presently there is not enough time t o cover chemical calculations in depth in general chemistry and most analytical courses stress instrumental techniques. I n 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 descriptke 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 sunimarized in an appendix. Errors noted in this text were miiiimal. 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 t o coin new and ambiguous terms t o describe an extreme in the continuous gradation that occurs in bond covalency. I t 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 nom7 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 sodiuni forms at the mercury cathode instead of hydrogen gas even in an acid solution. The hook containe a very good selection of rvorked 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 theni in the interpretive exercises and problem section. I n most cases the worked problems are clearly explained in a logical, stepwise manner.

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VOL, 38, NO. 13, DECEMBER1966

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There is B ruaspieuotm lack of figurea md dmgagrsmr throughout, md in many ~ 8 4 sLmr ~ s iucluon would greatly e l u d y l h e d i r d material. ALBa rmssing are refewnees to relared 80mw of mformation which might be usehrl u) the s~nou8aradmr. RnaUy, r e f c r a w in thc text S R I ~ u) wnment worked probkm at the end 01 each chaptar would have been helpful in mmlnling Ihr tleory n n d calculations. In spice ai che above c h e i - , thrS book does help fill a pap m tern available for the teaching of ionic q d b rium throrv and deulatiooe. I&

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treats ionio equilibrium in depth and in thia respect fulfills the author's aims in writing a supplementary text for general chemistry and quantitative anslysis. A book of this type deserves inolui o n into the chemistry curriculum but unfortunately an already overcrowded schedule of c o u m may prevent ita me exeept as B supplemantal text. Ihm&rd M&S 64 Ch.miwl Am6 p i s . 6th .d. V d r 11.4 ond 1111 Inshummlbl Method.. Fro& Wdeher, ed. zviii 974 nnd Zi .

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Tamto,T a a t o , O&, C&. This hoak, prepared by. 86 ,authors, contains in Volume A a disousslon of'41 instrumental methods of analysis intended to provide B general understanding of the principlee of instnunentation; as well as the scope, advantages, and limitatiom of each technique. Each, method includes & discussion of the basic principles and the reered equations, the arrangement and operations of the funotionsl psrts, and detailed direction for each step of the technique. Part I1 of V o l w A and B deal with the spplication of th8 instrum e n a tl methods to special materials which in w e r a l 8 2 . ~the same m those of Volume I1 with some exceptians m the case of thw materials which have .received adeqmte coverage in Volume 11 of this series. Included in the chap tern dtaling with materials are new cha~terson food and semiconductors. &oh of the 23 chapters on materiale pmides practical information on manipulation, accuracy of meQBUFprmen, and mtmthl muma of error for the v&us mtmmmtal methods. In Volume A eU of &he isatrurOental methods which are mcluded, mhik they ( m o t be 00nsHiered steadard methada in the mrm uaed m prenow volumm, have been widely wed, or at lesst, dfectively uaed for VI) which s nonmst have, for any reaqon, pr ferior. In addition, methods have b ineluded where they we known to be usefut in w1vk.g speersl pmblems and where they may be helpful in sussest kip m h l e approaehw forthe develop m t of other required methods. The design of the volumas rillStimulste inter& in the eatrmsicm of the vmow inatnunental tmhuiquw to the m1vk.g of snalycicsl problm. Thus, it ia not aplly B hmkof wipes hut &e a mum of imprntion for the d y h e a l reseprpher. EBsentislly, while the book is -tad towrd the practising analyst, rt &odd be mthb the mch of the malytical no& and mwt certamly it should be at the d i s p d of the tesesreh d y s t . &me of the chaptars-ea., the dwtmmetric and rwhoimtapic m&d++uld be d d e r e d in the nature of an upper level analytic81 text book with d e t d and infarmation of praetid value tw often l a m ! & m those at p r a m Ilvsilable. However,

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