Laboratory Experiments in Organic Chemistry (Adams, Roger

Roger Adorns, John R. Johnson, and. Charles F. Wilcox, Jr., Maemillan Pub- lishing Co., New York, 1979. vii + 538 pp. Figs. and tables. 24 X 16.5 cm. ...
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book reviews rtudent*, with proper attention to technique. can p;tducrn rr me that 'while not area1,dws rise alwvr the mrd~ocrr:' Immrdiatelg f l w n each chapter hmdina is n list d : l - L u kr)worda and phrnsel indieatkg the important concepts to be dealt u ith in the exoeriment. A discussion.. raneina - fmm a short paragraph to several pages, foll~. o w- the kewnrds. %,me of thechaoters have , questions a t the end, but most do not. IR,'H nmr, and I3C nmr spectra of starting materials indlor products are frequently presenteJ. The hook has wide left-hand margins in which one finds illustrations. cautions, terse advice and descriptive phrases, structural formulas, and other pertinent items. Mild carcinogens, such as benzene and dioxane, are used in a number of experiments, but caution i . always advised and the students are admonished to perform operations involving these agents in the hood. Occasiouallv an estimation of time needed to rc,mplr.tr nn rrprrtment 1% I~stcd,hut must d t c n nu wtimatwms a m g r w n 'l'hua lor instructors on strict whrtJutes, n litrlc exprrience may be necessary to gauge student laboratory t h e . Directions seem clear and illustrations appear often. Many experiments are unique. Coverage of techniques and reaction types is thoroueh. The authars'obieetives are to in~~~~

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These are laudable goals, and the book seems well designed t o achieve them. Loren L. Braun Idaho Stale University Pocafello.ID 83209

Laboratory Experlmenls in Organic Chemistry

Distillation, melting points, crystallization, sublimation, extraction, and chromatagraphy, which has been expanded and includes gas-liquid chromatography, are covered well in the separation and purification section. Carbvn tetrachloride, benzene, and chloroform have been replaced by less hazardous solvents. In the preparation and reactions seetioc abuut ten experiments deemed too dmgerous today have been replaced by several new experiments. A chemical kinetics experiment on the solvolvsis of tert-butvl chloride is

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Roger Adorns, John R. Johnson, and Charles F. Wilcox, Jr., Maemillan Publishing Co., New York, 1979. vii 538 pp. Figs. and tables. 24 X 16.5 cm. $13.95.

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Over fifty years ago, Roger Adsms wrote the first edition of this undergraduate laboratory text. Now, several years after his death, Johnson and Wilcox have revised the sixth edition. The seventh edition is similar t o the sixth, hut changes t o bririg the text up-to-date have been made. The text begins with a 150-pagesection on seoaration and ourification. Three hundred pages on the preparation and reactions of typical organic compounds follow. Next comes a 35-page section on the identification of organic compounds by chemical and spectroscopic methods. The text euneludes with 2 pages of suggestionsfor supplementary experiments, a 13-page section on the literature of organic chemistry, a 9-page appendix dewted mainlvto some orowrties of aauews

tunate. The identification section includes 17 pages on chemical methods and 20 pages an spectroscopy. Several of the experiments in the preparations section now include ir, nmr, and uu-"is spectra in contrast to the sixth edition which had none. Johnson and Wilcox state in their oreifice that n "rpecia1tmturc"uf !hi\ ed~tirm.s ~ t t c n t tc, h sacty bnmght about malnly hy minimizing student exposure to noxious chemicals and carcinogens. Laboratory safety is a rapidly changing subject so an instructor needs to be alert to new government regulations and findings on toxic chemicals. Any text will soon be somewhat out of date in this area. Fcsr example, thea~thc.rspointoutthat uninrulnred rrqlitanre * i r e heaterl for oil hdth. ore agaicsr OSHA rc,rulatiuui; nmlthrr very recent text advaestes their use. The authors could have been more thorough in eliminating a few hazardous chemicals. Benzene, whose use is prohibited in many laboratories, a t least a t the beginning student level, is used in several experiments I see no reason for keeping experiments an the nitration of benzene, on Friedel-Crafts alkylation of henzene, on the use of benzene in recrystallization ( p . 4 4 3 , or in using benzene in establishing the properties of hydrocarbons. In the latter two cases, no mention is made of benzene's hazardous nature. Hydrazine hydrate's toxic properties are mentioned (p. 4431, but anearlier use (p. 381) goes without warning. Similarly, 1,2-dichloroethane is used in tlc with warning of its possible mutagenic nature (p. 137),hut earlier (p. 5 3 , where its use in fractional distillation is suggested, no mention of any hazard is made. Such omissions are regrettable. Since many notes advising "Caution" are found throughout the book, their absence implies safety. Perhaps the author's attitude toward carcinogens is summed up in the footnote on p. 318 lamenting the demise of the preparation of benzidine: "it is unlikely that one exposure to a minimal amount of benzidine could have a deleterious effect." I hope they are right, but some scientists think otherwise. Bearing in mind that experiments need constant reevaluation with regard to safety and that a few in this text are, in my opinion, unsuitable for undergraduates, I believe that the strengths of this edition outweigh its weaknesses and on balance make it a strong contender for use in the undergraduate lahoratory. There are enough good experiments of various kinds acceptable by today's safety standards to satisfy most instructors, ~

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Kenneth K. Andwsen Universityof New Hampshire Durham, NH 03824

A26 1 Journal of Chemical Education