Chemical demonstrations: A sourcebook for teachers, volume 2

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This internationally recognized authority on laboratory safety benefits from significant revisions t o cover the continuing developments in technical and statutory matters that have taken placein the five years intervening since issue of the prior edition. New material is presented with the same clarity and high competence characteristic of earlier work. An added chapter by Howard Fawcett outlines some distinctions between US and UK legislation and practices, thus increasing thedirect usefulness of the book on this side of the Atlantic. The new edition is not visibly larger, hut the use of a small (still readable) type provides more information per page. Chapter 8, Hazardous Chemicals, again is distinguished by yellow pages. Although thenumbers and classes of covered substances have been increased only from 480 t o 490, there have been valuable additions to original information. Cross references now cite the third edition of Bretheriek's comprehensive Handbook of Reactive Chemical Hazards (Butterworth. 1985). All wrkerpin chemical and biological research lalwratories will profit from easy access to rhis reference. it is an rxcellent guide togoud practice and a quirk reference when there is need fur caution. My only caveat is this: the section on fume houds fails tostress thr importance of a n apprupriatr air supply (nut just in quantity and qualitv but a h m how t h e m isdelivered t o t h r l~boratorvrin determining containment by t h e hbod. There is no warning that increasing the exhaust rate, say to 150 fpm, may result in poorer performance as a result of turbulence. Tbeneed for keeping work a t least six inches inside the hood also should have been emphasized. The text does cite Mikell and Hobhs, this Journal 1981, pp. A-165, which includes cautions on work oraetices. We trust that thr npxt editim also will includr Mikrll and Drinkard, r h i s Journal 1981,pp. A-13, w h ~ r henlarges on theobligationsof a hood user. Apart from these misgivings, we rank the book tops in the field. Malcolm M. Renfrew University of idaho MOSCOW, ID 83843 ~~~~

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Chemical Demonstrations: A Sourcebook for Teachers. Volume 2 Lee R. Summerlin. Christie L. Borgford. and Julie 8. Ealy. American Chemical Society: Washington. DC. 1987. x 299 pp. Figs. and tables. 21.2 X 27.8 cm. $19.95 US, $23.95 F.

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The second volume of this popular and welromrsrries possrsses the samc strrngrls hut suffers from the same weaknesses as the first volume. Following the same philosophy and format of the first volume (reviewed in J. Chem. Educ. 1986, 63, A1181, the new hook, which contains 112 simple, safe, effective, and enjoyable demonstrations appropriate far introductory chemistry courses, is divided into 11 seetions-(1) "Introducing Chemistry," 5 demonstrations, 9 pp., the shortest section; (2) "Physical Changes," 11 demonstrations, 16 pp.; (3) "Reactions Involving Gases," 10 demonstrations, 16 pp.; (4) "Reactions of Some Elements," 11demonstrations, 16 pp.; (5) "Transition Metals and Complex Ions," 8 demonstrations, 15 pp.; (6) "Chemical Bonding," 8 demonstra-

tions, 10 pp.; (7) ''Energy Changes," 8 demonstrations, 13 pp.; (8) "Solutions and Solubility," 12 demonstrations, 22 pp.; (9) "Kinetics and Equilibrium," 13 demonstrations, 23 pp.; (10) "Acids and Bases," 9 demonstrations, 16 pp.; and (11) "Oxidation and Reduction Reactions," 17 demonstrations, 29 pp., the longest section. Among the perennial favorites included are nonadditivity of volumes, surface tension of water (the floating needle), liquid nitrogen, the Cartesian diver, hoiliug a t reduced pressure, plastic sulfur, burning magnesium in carbon dioxide, nitrocellulose, and supersaturation. The numerous novel demonstrations include colorful mixture separations, collapsing plastic bottle (atmospheric pressure), a hand-held reaction (production of ammonia gas), the "Aladdin's Lamp" reaction, a gas evolution oscillator, the glowing test tuhe, separating metallic iron from cereal, floating pennies, slow copper diffusion, changing coordination numbers (nickel complexes), the magic handkerchief. chromate dves. bendine a stream of watrr (polar rersur nonpdar molecul~s),wnves in a bottle, the nonpolar disk came, the disappearing coffee cup, hydrogen bonding in slime, a chemical hand warmer, electrochemical energy in a flash, chalk that glows in the dark, frozen solutions (electrical conductance), appearing red, disappearing red, a variation of the iodine clock, and the copper mirror. A new, fascinating feature is the inclusion of several demonstrations of historical interest, e.g., oxidation and reduction reactions of indigo, Ira Remsen's experience with copper and nitric acid (an excellent first-day demonstration; Getman, F. H. J. Chem. Educ. 1940,17, 9), chemical "miracles" from Parkes' The Chemical Catechism (1808), and Empedoeles' proof that air is a mixture (the oldest recorded chemical demonstration, 440 B.C.). Although the number of errors in this volume are fewer than in the first volume, they still detract from the authoritativeness and usefulness of this otherwise excellent book. Once again, thearchaic designation "ammu. nium hydroxide" (known nclt tu exist since the turn of the centurv; see Davis. J. H.J . Chem. Educ. 1963.30.hl) is usedfor aqueous ammonia, which is incorrectly designatOH- (p. ed as OH- (p. 117) and NHdt 136). The capricious and inconsistent blend of old-fashioned "molecular" and principal net equations (See, e.g., Kauffman, G. B. J. Coll. Sci. Teach. 1979,9, 83) is again used; sometimes the same species is written differently within the same equation. Strong electrolytes, e.g., H N 0 3 , HCI, H 2 S 0 4 , NaOH, KOH, and salts too numerous to mention are written in the molecular form, while weak electrolytes such as NHs (pp. 117, 1361, HC2H302 (pp. 35,461, and HgClz (pp. 121,122,202) are writtenas ions. Equations for reactions taking place hetween molten salts show aquated ions (p. 82), equations show species not present as reactants (CI~OQ . . .. on D. 10). . . and dissolved ionic species are depicted as undissociated tBatOH)l(sq, m p . lRO,.The ideaof"spcctator" ions is mentioned tp. 1211 but then almost completely ignored as "spectator ions" are included in equations. Failure to write principal net equations correctly results in an equation with coefficients not in the lowest terms (p. 131). Omission of charges (pp. 42, 121), incor-

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rect charges on ions (pp. 121,122), or incorrect formulas (pp. 10, 127, 210) give evidence of inattentive proofreading. Miscellaneous errors include Fen03 for FeaOd (p. 44) and aquo for aqua (pp. 71,77). Carbon dioxide is erroneously shown as furnishing sufficient [C032-] to precipitate CaC03, whereas OH- must be present for this reaction to oroeeed (0. 177). The term "campusition" rs used fur the reaction that istheoppuiite ~rf"dpcomposition",a use not sanctioned by any drctimnry (p. 441. Also, dissolving is not a reaction, a term that is limited to chemical changes (p. 88). Six appendices-"Cross-Reference of Demonstrations and Chemical Topics," "Properties and Preparation of Laboratory Acids and Bases," "Equipment and Reagent List," "Safety and Disposal," "Periodic Chart of the Elements," and "Atomic Weights of the Elementsw-add to the usefulness of the volume. Although the authors stress safety precautions, no mention is made of the reason for not storing Ag(NH&+ solutions (formation of fulminating silver nitride), and 100%Hz02 is described as a stable liquid! A colleague and fellow editor of mine has expressed extreme concern and chagrin about the contents of this hook. His local ACS section purchased "a goodly number" of volumes to present t o local high schwl teachers. When he perused what his section was preseuting-and personally endorsing by this act--, he detected "too many errors." The section may have been misled by the imprimatur of the American Chemical Society, the excellent reputation of the senior author (an MCA Catalyst Award winner), and my critical hut generally favorable review of Volume 1 (men culpa). As an author and editor myself, I am aware of the immense amount of time and effort required to write a hook, especially one of demonstrstions,agenre that is in short supply. Therefore I usually "lean over backwards" to give authors the benefit of the doubt. Since the authors have apparently chosen to ignore my criticisms of the deficiencies of Volume 1, I cannot, in all good conscience, give Volume 2 a favorable review. Caveat emptor. Prospective buyers should examine the book carefully and make up their own minds. ~

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George B. Kauffman California State University, Fresno Fresno. CA 93740

Titles of Interest -1986-

Maximum Concentrations a t t h e Workplace a n d Blologlcal Tolerance Values for Working Materials 1 9 8 6 DFG Deutsche Forschungsgemeinschak VCH: New York, NY, 1986. 82 pp. Figs. 17 X 24.1 cm. $15.00. Report No. XXII, Commission for the Iuvestigation of Health Hazards of Chemical Compounds in the Work Area. (Continued on page A172)

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J u n e 1988

A171