REFENT BOOKS

each step in writing by reference to a law or definition, or by mathematical reasoning. ... topics of units, formulas, gas laws, valence, molecular an...
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REFENT BOOKS GENERAL CHEMISTRY PROBLEMS.William M. Spice,, Associate Professor of Chemistry, Georgia School of Technology, William S. Taylor, Professor of Chemistry, Georgia School of Technology, and Joe D. Clary, Assistant Professor of Chemistry. Georgia School of Technology. John Wiley and Sons, Inc., New York, 1943. v 120 pp. 2 figs. 14.5 X 22 em. $1.25. No one denies that problems are the bugbear of most students in pneral chemistry. These authors approach the subject b y telling the student, " all education is self-education. You must do the work. The purpose of this workbook is t o help you teach yourself . . . The difficulty (in working problems) is not in the mathematics, hut is due t o a lack of understanding of the principles, an inability to be exact. and a tendency t o work problems by a mechanical process. . . . We require you to justify each step in writing by reference to a law or definition, or b y mathematical reasoning. . . If a student can work a given pmblem in this way, we are justified in believing t h a t he is capable of solving other problems of the same type." The book "attempts t o teach (1) the necessity for (written) justification of every step taken in the solution of a problem, (2) the importance of thinking in terms of chemical units (moles. gram-atomic weights, gram-equivalent weights, etc.), (3) the elementary ideas about significant figures. (4) the use of logarithms and the slide rule. (5) the importance of mentally checking all results." Certainly these aims are laudable, although for noa-engineering students, (the authors are all faculty members of the Georgia School of Technology), number 4 may seem superfluous. Certainly, too, these aims are met in excellent style. The usual topics of units, formulas, gas laws, valence, molecular and atomic weights, problems based on equations, solutions, and equivalent weights are accompanied by a significant chapter on Use of Chemical Units of Quantity, and by goad discusisions of exponents, logarithms, and significant figures. Purists, and teachers of advanced courses, may find room for quibbling over such items as the use of cc. rather than ml.,the definitions of valence. normalitv and eauivaleut weieht. - . and the use throughout of the Arrhenius theory of ionization. I n the light of exact knowledge exceptions may be taken, but this reviewer is content with the course chosen. The only fault this reviewer finds with an excellent text, well written, well printed, is with the sometimes elaborate efforts t h e authors have made to eliminate the use of proportions. In short, all teachers of general chemistry should consider well the use of this book in meeting what should not be, hut is, t h e greatest difficulty faced by their students. EARLW. PHELAN

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the help of the fire department in fighting a serious fire, so the smoke-eatercan profit by collaboration with a chemist in studying the scientific aspect of fires, avoiding technical errors, and realizing that the fundamental problem is one of controlling a chemical reaction. ELBERTC. WEAVER

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I N T ~ O D ~ CCOLLEGE T O R YCHEMISTRY.J . A . Babor, Associate Professor of Chemistry, College of the City of New York, and A . Lckman, Associate Professor of Chemistry, College of the City of New York. Thomas Y. Crowell Company, New York, 1941. xiii 663 pp. 138 figs. 15 X 23 cm. $3.50. The text consists of 48 chapters covering some 625 pages, plus 9 pages of appendixes which include a four-place table of logarithms and a n index. I n the index many of the references to chromium and its compounds are misplaced. The book is intended for two types of courses: classes cornposed of students who have had no high-school instruction in the subject and classes composed of both students who have had no high-school chemistry and those who have had an elementary course. This result has been accomplished largely by elimination and rearrangement of material found in the text, "General College Chemistry," by the same authors. For example, the chapters dealing with colloidal solutions and radium and radioactivity appear t o be identical, word-for-word, in the two texts. In other portions of the text, by the elimination of paragraphs dealing with the more advanced discussions the material is brought within the scope of this hook. This has been done in such manner as to detract in no wise from a logical development of the subject. Theoretical matter is distributed throughout the first half of the book and not all given in the first few chapters before the student has had opportunity to acquire same chemical knowledge. The theoretical material is modern and is explained in an understandable fashion. The BrBnsted theory of acids and bases is introduced after the limitations of the Arrhenius concept of ionization have been discussed, and thereafter is employed exclusively. Molecular and atorpic weight determinations are taken up in chapter 8 after the student has been introduced to oxygen, hydrogen, and water, and the kinetic molecular theory. This is the chemist's method. No mention is made of the mass spectrograph a t this point, but brief mention of it is made in chapter 20 in the discussion of atoms and isotopes. The reviewer wishes more writers of freshman chemistry texts would make use of the ohvsicist's method of determining atomic weiehts since less confusion results in the beginner's mind. The chemist's methods could come later. The organic chemistry content consists of four chapters: carbon and some carbon compounds, the hydrocarbons, derivatives of hydrocarbons, and carbohydrates. Any one or all of these chapters may be omitted if so desired. There is also a 13-page chapter a n food and nutrition. Brief menticn is made of the essential foods for man, together with two tables on composition of the edible portions and ash of a number of common foods. The discussion ol metals occupies 138 pages and is devoted to the more common metallic elements. I t is 5 0 arranged that a course in qualitative analysis may be simultaneously studied.

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THESCIENCEOF FIREFIGHTING.John J. Mccarthy. W. W. Norton and Company, Inc., New York, 1943. 265pp. 15figs. 13.5 X 20 cm. $2.50. This timely hook by the assistant chief, in command, New York Fire Department, who has spent 29 years in active fire fightiug is from a practical authoritative source. It contains examples of fireaghting strategy, suggestions for mutual aid. a n d an appendix an hydraulics. A title such as "Techniques of Fire Fighting and Fire Prevention" would be more descriptive. The scientific aspect of the subject is limited, discussion of the fundamental nature of fire occupying only part of a chapter. Just as a chemist needs

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The applications of chemistry are not overlooked. Many references occur in which the student is shown the use made of chemistry in medicine, industry, and agriculture. On the whole the reviewer would designate this as a we& written, logical, and teachable text on freshman chemistry, and i t is his further feeling that one who properly completes this work should he qualified to take up subsequent courses in chemistry. H. H. KING KANSAS

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beginner's attention is much mare readily facusedon the special features of these drawings than on all black figures. This is a carefully developed elementary text in electricity. light, and modern physics, with a decidedly modem viewpoint. I t should be suitable for students who want an interesting picture of the electrical side of physics, with all difficult mathematics and confusing experimental detail omitted. E. P. L I ~ E TAB P ~ L L PEXBTBB S ACADBXY EX=%%*,NEW HAWPS-B

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ELECTRONIC PHYSICS. L. Grant Hcctm. National Union Radio Corporation. Herbnt S. L&, University of Buffalo, and Clifford E. S o u l a . University of Buffalo. The Blakiston Company, Philadelphia. 1943. viii 355pp. 289 figs. 15 X 22 cm. 8 . 7 5 . This is not a hook on electronics, in the usually accepted sense of the word. The title suggests that the hook deals with the physics of electronic devices; instead it is an elementary textbookon electricity, light, and "modern" physics. The authors state that the text is for beginners. For complete comprehension, however, this hook should he preceded by another on mechanics and heat The ideas and units of force, work, and power are used without definition in their mechanical sense, and knowledge of the calorie, methods of mixtures, and specific heat is assumed. The authors also state that. "This text has been used with callege freshmen and sophomores, pharmacy classes, special courses in ground school for pilots, students in Signal Corps radio classes, and a few high-school classes." The treatment. however, is very elementary. Although the hook contains 350 pages, the general level of difficulty does not approach that met in the usual text for first-year college physics. For example, the treatments of electrolysis and batteries fail completely to present ideas of the chemical reactions a t the plates. Only a disturbingly simple picture of the transfer of electrons is given. There is no distinction between the e. m. f. and the terminal voltage of a battery, though internal resistance is included. Mention is made of shunt, series, and compound motors, hut no idea of the advantages of each type is given. Snell's law is mentioned briefly, but not stated or used mathematically. Total internal reflection is demonstrated. hut no mention is made of the value of the critical angle, even for glass or water. I n fact, a very Limited use of mathematics is made throughout the hook. Thii text does have its good points. The large number of pages and the lack of any advanced and complicated treatment give the authors an opportunity to develop a t length the ideas which are often all too briefly covered i a the standard college text. Particularly good is the treatment of magnetism, electric meters, inductance and alternating current, electron tubes, the electromagnetic spectrum, and transmutation of the elements. Almost all of the electrical phenomena are presented from the electmn-proton point of view. For instance, the ideas of magnetism are first presented in terms of electromagnetism of moving electrons, and then related to permanent magnets by corrsidcriug the electrical nature of aronxr. This approach allows a lucid if elemenraw description of photoelectriciry. x-rays, electron tubes, radioactivity, and transmutation. A feature of the text is the use of color in the line drawings. I n general, the material parts are represented in hlack and the special or electrical features in red. The authors claim that the

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SE~-MICRO QUALITATIVE ANALYSIS. J a m s T. Dobbins, Professor of Chemistry, University of North Carolina. John Wiley and Sons, Inc., New York. 1943. x 423 pp. 4 figs. 15 X 22 cm. 83.00. The two outstanding features of Professor Dobbins' c-e in qualitative chemical analysis are already familiar t o the readers of THIS JOURNAL, through his recent articles in collaboration with his coworkers; these are (1) the shortening of the time required for identifying the usual cations. and (2) a complete systematic scheme of separating the common anions. The first objective is accomplished by the elimination of many of the standard separations and the judicious application of organic reagents. The group separation of the anions is effected by consecutive addition of calcium, barium, cadmium, and silver acetates, under specified hydrogen ion concentrations. From the standpoint of the average student, both of these innovations constitute genuine advances over the more standardized procedures. With no increase in laboratory time, a greater number of "unknowns" can he analyzed with a reduction in tedium and with heightened interest. For the nonprofessional chemirtry student, these advantages may very well outweigh the slighting of "fundamental" chemistry. It is unfortunate that this new textbook fails to take advantage of equally important developments in theory. I t is really discouraging to find that the very fruitful modem theory of electrolytes, now in its 21st year of development, is still considered too difficult and obscure for immature students. "The principles of commou-ion and uncammon-ion efiects and solubility product may he interpreted most easily on the assumption that molecules [of salts] exist in solution and that an equilibrium exists between them and their ions." An entire chapter is devoted to the "Uncommon-Ion Effect," in the effort to bring the complex behavior of aqueous solution into conformity with the simple ~ostulatesof the Arrhenius theam. While the ideas mav he verv 'reachable." they are not constnlcrive in advanciug the trainkg of students in chemistry as a science. AF a matter of fact, m m t of the examples of the "uncommon-ion eflmt" are usually r l n 4 fied as examples of weak acids or complex ions and are not examples of what is called, more commonly, the d l - e f f d . The hook has few sketches illustrating laboratory techniques, has no periodic table, and no references to the literature. A 1-e number of introductory experiments are included t o give the student the background for carrying out the analytical procedures. Professor Dobbins' hook can he recommended only for students who are not planning to become professional chemists. For the latter, this reviewer believes, a more fundamental course, both from the standpoint of theoretical treatment and laboratory practice, should he offered. LAURENCE S. FOSTER

If you are a trained chemist, you have 1999 neighbors in America who are

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