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ANALYTICAL CHEMISTRY
ing chapter on applications. The topics included range from storage batteries through electroanalytical applications to corrosion. In summary, this treatise is a valua ble contribution which will be useful as a reference book for researchers, teach ers, and students of electrochemistry. In view of its breadth and depth, the few objections raised appear minor in deed. Semimicro Qualitative Organic Anal ysis. Systematic Identification of Organic Compounds. 3rd ed.
N. D. Cheronis, J. B. Entripin, and Ε. Μ. Hodnett. xi + 1060 pages. Wiley-Interscience, Inc., 250 Fifth Ave., New York 1, Ν. Y. 1965. $29.50. Reviewed by W. C. WUdman, De partment of Chemistry, Iowa State University, Ames, Iowa. The third edition of this well-known reference work represents an expansion of almost 300 pages. Increased em phasis has been placed on newer and more refined laboratory techniques for the separation and purification of small amounts of organic material and on a more complete listing of known organic compounds. The book is divided jnto four parts: (1) The techniques of organic analysis, which includes subsections on small scale equipment, separation and frac tionation methods, (2) The tentative identification of an unknown, (3) Final characterization of an unknown, and (4) Tables of organic compounds with their constants and derivatives. It is recognized in the preface that instrumental methods have become in creasingly important in analyses of samples in the 50-1000 mg. range. Ten pages of the book are devoted to intro duce these methods and to provide im portant references up to 1963. Most structural studies of organic compounds require pure samples. Thus, the information in part one is of importance to all organic chemists and this section represents one of the most valuable portions of the book. How ever, recent developments in two di mensional thin- and thick-layer chro matography are not included and gas phase chromatographic techniques are not discussed beyond the simple alkyl benzenes. If one is so fortunate to have grams of an unknown substance and so un fortunate to have no instrumental facil ities, the entire book will prove to be exceptionally valuable. The cost of the book eliminates its use as student text. However, the wealth of information on the separation, purification, and physiI cal constants of organic compounds
should make the book a standard library and laboratory reference. Instrumental Methods of Analysis.
4th ed. H. H. Willard, L. L. Merritt, Jr., and J. A. Dean, xviii + 784 pages. D. Van Nostrand Co., Inc., 120 Alexander St., Princeton, N. J. 1965. $10.75. Reviewed by George Latter, Cali fornia Institute of TechnoL·gy, Pasa dena, Calif. The 4th edition of this book is an ex pansion and revision of the previous volume. A number of chapters have been added, more problems can be found at the end of the chapters, and all detailed instructions on the use of individual, commercially available, in struments have been deleted. Presum ably written as a text for an advanced instrumental analysis course, the book falls short in many respects. Most of the material is presented in an over-simplified manner. There is no discussion on the use and care of modern tools found in most laboratories —e.g., recorders, oscilloscopes, amplifi ers, etc. Except in the cases of optical absorbance and radiotracer techniques no critical discussion of the precision and accuracy of the various methods can be found ; instead, cursory and mis leading statements abound which the student must take on faith. The first two chapters, new in this edition, cover basic electronics. Most students will undoubtedly have had some experience with the laws of Ohm, Ampere, and Kirchoff, which are cov ered ; yet a discussion on the techniques of generating, detecting, and measuring electronic signals is totally lacking. The rule for adding resistors in series and parallel connection should be known to the average student at this stage, and a mention of the problems and techniques of impedance matching would have been more appropriate to make him aware that such matters must be considered. The student would be hard put to find the "second" output of the opera tional amplifier described on page 29. The amplifiers depicted are equivalent, both are single input devices as shown. The discussion of electronic spectra beginning on page 82 is very confusing. The authors ignore quanta or quantum mechanics. Problem 16 on page 113 asks the student to estimate e for per manganate and dichromate from the data contained in Figure 4-17 which happens to be a schematic optical di agram of a reflectance attachment. Figure 4-19, which does contain the ab sorption curves, does not indicate the path length and therefore the problem could not be solved in any case.
