Characterization of organic compounds

answer" is a phenomenon whieh is fre- ... ing, from the horsepower of a man's auto- mobile, whether he is ... the solution is heated on a water-bath u...
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the "derivation" ends with "the right answer" is a phenomenon whieh is frequently observed in derivations on student examinstion papers. As Leibnia sdd, "le vrai peut &re tire du faux." The phrase "stmdy state" should prohably read "standard states." Page 134 implies that, without having any information as to the actual eoncentmtions (or activities) existing within a system, one is able to know whether the system lies to the left or the right of equilibrium, from the sign of AF". This would be as much a miracle as determining, from the horsepower of a man's automobile, whether he is about to set out on a trip or has just returned from one. As applied to exergonic and endergonic canditions, this confounding of AFo with A F of a reaction unfortunately occurs in many biochemistry textbooks. Errors of the sort cited are not limited to this particular textbook of biochemistry. The widespread continued use by teachers of biochemistry of textbooks which perpetuate such errors does not speak well for present standards of classroom instrnotion in biochemistry. The presence of such errors is the more difficult to explain in view of the ready accessibility of elementary physical chemistry textbooks in which these subjects are presented correctly. Colorodo State University Fort Collins

Charaeleriration of Organic Compounds

F. Wild, Research Chemist, Department of Medicine, University of Cambridge. Cambridge University Pnss, New York, 1958. Second edition. 306 pp. 15 X 22.5 em. $6.50. viii

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The second edition of this well-known book is identical with the first edition (1947) with the exception of the listing of some new derivatives with their physical constants and the revision of a number of melting points. Six lines on the bottom of page 32 have been omitted and a n supplied here from the 6rst edition for those purchasers lacking the earlier volume:

". . . a t s. rate sufficient to keep the solution a t 40'. After the final addition the solution is heated on a water-bath until a solid mess separates. The mixture is cooled to 0' in an ice-bath, and concentrated nitric acid diluted with water (10%) is added slowly until the reaction mixture is yellow. More solid is deposited during the addition of acid whieh is controlled so that the . ." tem-

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This hook is devoted almost exclusively to derivatiization; other subject8 u s u d y discussed in qualitative organic texts such ss separation of mixtures, determination of physical properties and the relationships of structure to physical properties are treated lightly. There is no discussion of, or directions for, the qualitative detection of elementpit being assumed that the student is already familiar with this procedure.

102 / Journal of Chemical Educotion

The tables include various types of derivatives not found in the usual qualitative organic text.

of Organic Chemistry" and the reader is assumed to he familiar with the basic eoncepts and theories of organic chemistry which are presented in the first and second volumes. However, the discussions ;ue Suulhurdrrn nl .\l~ntphra eo clearly written and so richly docf'huprr a,, C'hr,nt~al( ' o w p o n y umented with referenoes to original M t r . phza, 'I'