Chemical Calculations. Second edition (Long, J. S.; Anderson, H. V.)

Henry Holt and Company, New York, the metals. 1928. vi f 57 pp. 13.5 X 21 cm. S~RWIN. MASSER. 80.90. UTAH AGRICULTURAL COLLEGE. We are familiar ...
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Recent Books A Laboratory Manual of General ChemAND ANLEONB. RICHARDSON DREWJ. S C A R L E ~ JR., , professor^ of Chemistry in Dartmouth College. Henry Holt and Company, New York, 1928. vi f 57 pp. 13.5 X 21 cm. 80.90.

istry.

We are familiar with two extreme types of laboratory manuals. I n one, numerous short experiments of a descriptive nature are outlined with little or no discussion of the principles of chemistry. I n the other type there are only a few experiments outlined and they are of either a quantitative nature or in some other way designed t o develoo the theoretical side of the suhiect. This manual is made up of a very good combination of descriptive experiments and experiments of a nature such ss t o aid the student in an understanding of the theories of chemistry. There are a total of fifty-four exercises planned, many of which are made up of a number of short tests of the "test tube" type. The first three are directions for glass working, measurements of gas volumes,and weighing. The students' time is conserved by the inclusion of blank pages for notes and tables for the recording of data. The manual was prepared to accompany "General Chemistry" by Richardson, and numerous references t o the text are made. The directions are clear and concise, hut are rather abrupt. The reviewer would prefer that directions for an experiment be prefaced with a hrief discussion which would suggest t o the student a reason for performing the experiment. No such introductory matter is included by the authors. Their method is t o give directions and then ask questions on the significance of the results. The consecutive order of the exercises may perhaps best be designated as "conventional," unless one considers the plac-

ing of the experiments with sulfur before those dealing with chlorine an exception. Ionic equilibria and solubility products are well emphasized in the experiments with the metals. S ~ R W MASSER IN UTAHAGRICULTURAL COLLEGE Chemical Calculations. J. S. LONG,Ch.E., M.S., Ph.D., AND H. V. ANDERSON, B.Ch.E., M.S., Lehigh University. Second edition. McGraw-Hill Book Co., New York, 1928. ix 227 pp. 11 figures. 20 X 13.5 cm. $1.75. postpaid.

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This is a second edition of a hook which first appeared in 1924. It consists of fifteen chapters, dealing with such prohlems as thermometric calculations, density of solids and liquids, gas laws (including Dalton's law of partial pressures), definite and multiple proportions. GayLussac's law of combining volumes, grammolecular-volumes,derivation of formulas. halancing of oxidation-reduction equations by change in valence, normal solutions, gas analysis, thermal equations, electrolysis, mass law, and solubility products. The appendix contains tables of data useful in solving the problems. Each chapter contains a hrief discussion of principles, followed by ample lists of numerical problems, with and without answers. I n the preface the authors state that these problems were originally designed for use in the second half of the freshman year, using weekly recitations. The lists of problems appear large enough t o furnish a supply for three or four years' work, without repetition. The exercises are well chosen, and appear t o he arranged with a view t o increasing difficulty. They show as much variety of form as might he expected. The numerical quantities used are seldom

whole numbers, and the calculations might be unduly laborious unless logarithms or slide rules are used. The discussion of how much work of this kind should be included in the freshman course is outside of the scope of a hook review. However, there are many of us teachers who believe that the use of problems of this sort requires of the stndent closer thinking and a deeper understanding of the mathematical relations of chemistry than can be obtained in any other way, and who will extend t o the book a warm welcome. 3. H. R ~ E D Y UNIVERSITY OR ILLINOIS

cal part. He is told (p. 64) that "the addition of a base will cause the removal of hydrogen ion because hydrogen and hydroxide unite to form water:

and then hydrolysis is scientifically though briefly discussed on page 126. Examples could be multiplied. There is no mention of dissociation constants in the book and if the student is supposed to have become familiar with their meaning in a previous course there seems t o be no necessity for devoting page 19 to the antique definitions of acids and bases. The book could be much improved by Introductory Qualitative Analysis. JACOB distinguishing in the laboratory part beCORNOO. Assistant Professor of Chemistry a t the State University of Iowa, tween essentials and explanatory notes. The latter should have been written in and WARRENC. VOSBURDH, Assistant Professor of Chemistry a t Duke Univer- smaller type. Many pages could have sity. The Macmillan Co., New York been saved and the following of the direc155 pp. 3 figs. tions made easier t o the student. Such City, 1928. ix supel;8uous directions as asking the stu21.5 X 14 cm. $1.60. dent to become familiar with "the locaThis book is intended for a short course tion of drinking water and toilets" (p. l) in Qualitative Analysis occupying "thirty and "when the test is completed, the clock hours" of laboratory work. A very solution and the precipitate can be thrown short course indeed. away" (p. 60). are out of place in a work The hook is divided into two main parts. intended for college men. The first deals with laboratory directions A serious error occurs on page 62. and explanations (100 pp.); the second Nickel does not replace two hydrogens with the theory of analytical reactions from one molecule of dimethyl glyoxime (42 pp.). The second part might as well hut only one from each of two molecules. form part of a different book for little use The formula of the precipitate is not is made of i t in the laboratory directions. Ni02N.C~H.,as given, hut Ni(OlN.C,H7).. While the author's opinion is that "the This would be an unfortunate idea t o inacquisition of theoretical insight is not a stil in the mind of a future analytical result of simple volition, of persistent chemist. effort, or of memory on the part of the Although much may be said about the student" but that "it has its genesis in an theoretical part, which is ably written, the inquiring intellectual attitude," the relaboratory part contains nothing new, viewer fails t o see how this "inquiring in- much that is old and discarded, as, for extellectual attitude" can be stimulated by ample, the separation of magnesium from telling the student one thing in the lahora- calcium with ammonium carbonate, and tory part and proving that same thing t o the book cannot he recommended as a be wrong in the theoretical part. whole for a serious course in qualitative He is told (p. 67) that "lead ion unites analysis. with chromate ion t o give a precipitate of J. E. ZANETTI lead chromate," and the solubility prodCOLUMBIA UNIVERSITY uct is quite fully discussed in the theoreti-

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