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This concept lays primary emphasis on the sign and magnitude of the charge of the central atom of a molecular configuration as determining acidic or basic properties rather than the criterion of “salt formation” which is regarded as an incidental phenomenon. The present volume is especially valuable since it discusses acid-base dissociation in such solvents as ethyl alcohol. On the basis of Bronsted’s definition both ethyl alcohol and water are bases, but water is four hundred times as strong a base as is ethyl alcohol; this accounts for the difference in behavior between aqueous and alcoholic systems. This section of the book especially appealed t o the reviewer. In the section devoted t o the properties of indicators we find an excellent theoretical discussion, followed by a description of the various indicators, including formulas, melting point, and other physical properties, methods of purification, solubility and p H range and their suitability for use under various conditions and with various solvents. A new definition of an indicator is proposed, i.e. “Indicators are (apparently) weak acids or bases, whose inogene or aci- (or baso-) form possesses a different color and structure than the pseudo or normal form.” The third section of the book, dealing with the colorimetric estimation of hydrogen-ion concentrations, deals with the preparation and properties of buffer solutions, the technic of the colorimetric determination of hydrogen-ion concentration, the sources of error in the colorimetric methods, including an extended discussion of the effect of salts, proteins, and other colloids, temperature, etc., with the last chapter devoted to indicator papers. The book closes with an appendix of six tables showing the ion product of water a t various temperatures, the ion activity product of water, the activity coe5cient for various concentrations of electrolyte solutions, an extensive table of the dissociation constants of approximately one hundred and twenty acids and bases, including such compounds as the alkaloids, phenols, etc. (The reviewer wonders why the amino acids were omitted from such an imposing list, for they certainly are more commonly worked with than are many compounds included in the table), and an interpolation table for converting fractions of pH into Ca values. Excellent author and subject indices close the volume. It is a book filled with valuable discussion and tabular data. The fact that other volumes on the determination of hydrogen-ion concentration are available should not deter one from purchasing this book, for it contains much material not otherwise readily accessible. It should be in every chemical library and in the hands of everyone interested in the control a,nd measurement of hydrogen-ion concentration. Ross AIKENGORTNER.
Die Struktur der Atomkorne. By DR. SIEGMUND 22 x 15 cm.; 50 pp. STRANSKY. Leipzig u. Wien: F. Deuticke, 1932. Price, 4s. 9d. Dr. Stransky’s monograph on the structure of the nucleus is entirely original and entirely speculative. There is evidence in favor of the conclusions he draws but it is of a numerical kind, in which the numbers are confined rigorously t o integers. He does not consider other theories of the subject he is writing about, and it is at once patent t o a reader t h a t little reconciliation is possible between Dr. Stransky’s views and the main corpus of knowledge that has been ground out of the research of the past twenty years. They lie, indeed, so far outside of the main stream of theory and experiment t h a t I fear atomic physicists may fail t o give them the patienl consideration the author would like them t o get. Dr. Stransky is a modern Prout, a Prout, moreover, who has had in his time thf discouragement of a Newlands. He tells us that for forty-five years he has occupiec himself a t invervals in arranging units of mass (protons, they would now be called: in such patterns that the most likely of them sum to the masses of the common ele ments, and that he has not always been able to get his work published. Like Prou
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he has started from the assumption that protons are the stuff from which all matter is built. The new points are that the protons are probably arranged in the nucleus in hexagons or fused hexagons like the CH groups in benzene, naphthalene, phenanthrene, and so forth, and secondly that the masses of the atoms of the elements of one particular group are based on one another. (For this purpose the subdivisionsA and B of the groups of the Periodic Classification are ignored.) The atomic weights of copper and silver, for example, are based on those of lithium and the alkali metals. Just as naphthalene may be regarded as two benzenes less four carbon atoms, and picene as five benzenes less eight carbon atoms, so are heavy elements of a group so many times the masses of simple elements of the group less so many hydrogens. Thus Na, 23, is 4Li - 5, the atomic weight of lithium being taken exactlyas7, and Cs, 133, is 6Na - 5; the reason for subtracting 5 in these cases is that when four or six “benzene-rings” of protons are joined together most compactly there are five points held in common, and consequently no protons there. Occasionally some latitude is allowed in deciding what arrangements are most compact, and the various alternative masses arrived at serve as the various isotopes of the element under consideration. Thus nine “bricks” of twenty-three protons can be simply arranged so as t o have either eight or ten points of contact with the possibility that the element so built up can have two alternative masses differing by two units. Much of the book is occupied with diagrams showing the patterns in which the nuclei of the atoms of the different elements are arranged by Dr. Stransky. The simpler ones look like the diagrams of carbocyclic chemistry; the more complex resemble snow crystals viered through n, microscope. Dr. Stransky’s general theory may have been plausible in days when atomic weights were thought t o be whole numbers, or even in the early days of nurlear theory when the nucleus was regarded as built up of hydrogen protons, but the experimental work of F. W. Aston completely disposes of Prout’s hypothesis in any form. It is the helium nucleus which is the chiefest brick in the nucleus, with the proton and possibly the neutron and the “demi-helion” as subsidiaries. None of these is any sort of arrangement such as Dr. Stransky postulates. The great importance of these ultimate units and the nuclei which are built from them at the present time is not that their masses are 4, 1,2, 133, etc., but that their masses are in excess or defect of integers to an amount which is a function of their closeness of arrangement in the nucleus. Further, Aston has shown that there is little evidence of what might be called a periodic arrangement of the nucleus akin t o that of the planetary electrons in an atom; if there were, one might deduce from the masses of the isotopes of tin those of the isotopes of lead by adding a constant amount, such as 88, to the masses of tin. To some degree this works, but it is not so universally applicable as to be regarded as an arrangement. If further considerations were needed to be quoted against Dr. Stransky’s theory, the experimental work on the discription of the nucleus which has been going on at Cambridge since 1919 would suffice. What is known of the nucleus from these experiments (and it is almost everything that is known) has no resemblance t o Dr. Stransky’s speculations. Nevertheless Dr. Stransky has shown great ingenuity in his work. It is quite the best exposition of ‘Proutism’ t h a t has appeared, and if i t encourages others to begin a study of how the nucleus is built u p from the real ultimate units, his labor will not have been altogether in vain. A. S. RUSSELL. Chemische Technologie der Neuzeit. B y 0 . DAMMER. Second and larger edition, 5th volume. 19.5 x 27.5 cm.; xvi 876 pp. Stuttgart: Ferdinand Enke, 1932. Price, bound RM.79, unbound RM.5.
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