A Text-Book of Inorganic Chemistry. By F. Ephraim. Fourth English

concentration approaching 1 mole, serves to give a notable increase in fluorescence brightness. When fired for a long period at1250°C. it loses its f...
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and its fluorescence remained unaltered. At 1400°C. it sintered don-n in 15 min. to a semi-fused mass! hut it still maintained the scheelite pattern and considerable fluorescence. SL7\11\I.4RT

The magnesium tungstate phosphor always exhibits the monoclinic structure of I\lgTT704,even in the presence of an excess of magnesium oxide xvhich, a,t a concentration approaching 1mole, serves to gire a not,ableincrease in fluorescence brightness. Khen fired for a long period at 1250°C. it loses its fluorescence in one of t8xoTmys, depending upon the concentration of magnesium oxide: (a) by conversion into a semi-glassy state, if it contains 0.5 mole or less of excess magnesium oxide; (b) by alteration into another crystalline modification, having presumably the formula I\Ig,TT05, if it cont'ains 1 mole or more of excess magnesium oxide. lMg,W06 differs from MgW04 not only in being non-fluorescent but also in being stable only above 1200°C. or thereabouts and in having a melting point xhich lies ab0.i-e 1460°C. The quantum efficiency of excitation of the phosphor is near unit,y for t,he range 2500-295Oa. REFERESCES (1) BROCH, EIX.\R: Z . physik. Chem. lB,415 11928). ( 2 ) FOSDA, G . R . : J. Phys. Chem. 43,5 i 4 (1939). (3) FOTLKE! T . E . : U. S.patent 2:203,6S2 (June 11, 1940); 2,232,780 (February 25, 1941). ( 4 ~ 1F R E R I C HR Y., : Saturn-issensciinften 26, 681 (1938). ( 5 ) THAYER, R.1.: ASD BARKES, B. T . : J. Optical SOC.Ani. 29,131 (1939). (6) LTTERHOETES, W , : Elekfrisclie Gaaentladu,igslampeii. Julius Springer, Berlin (1938).

S E W BOOKS A Text-Book of Inorganic Chemistry. By F. EPHRAIM.Fourth English edition by P. C. L. Thorne and E. R. Roberts. 24 s 16 cni.; sii 921 pages. London and Edinburgh: Gurney and Jackson, 1943. Price: 28 shillings net. This work, now published in the fourth English edition, is probably well known to most readers. It is a n advanced test-book in which the treatment follows a n order of topics rather than a grouping of individual elements, with chapters on theory. I n considering compounds. the order is usually t h a t of Valence rather than the periodic law order. The book is deservedly popular and can be recommended t o advanced students. The reviewer has noticed a number of places in the text which seem to call for consideration n-hen a new edition is required. It is impossible t o notice all of these in a short review, but some indication may be given of the kind of thing which is meant. The theoretical side of the book is the least satisfactory, although i t has been improved in the English editions as compared v i t h the original. The chapters on atomic structure and valence contain a number of errors and obscure statements; for example, the force between the electron and nucleus is said t o be quantized, the uncertainty principle is obscurely stated (page 3), i t is said t h a t the outer electron shell of 8 of the inert gases is confined t o those of low atomic number, a special parachor value is given for semi-polar double bonds, etc. The short account of the quantum theory of valence on pages 53-57 is good as far as i t goes, but the statement of the quantum-mechanical basis on page 53 is defective, and the symbols s, p , d for the electrons are not defined. The assertion on page 56 t h a t

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hybridization involves a tendency to form bonds with “rhe greatest possible energy” is misleading. On page 89 the transuranic elements are first dealt with in some detail! and then it is said that’ they do not exist. This reIuctance to omit obsolete inforrllation turns up in other parts of the book. The statement of the second lan- of thermodynamics on page 92 is not intelligible t o the reriener. The descriptive part of the book is more successful. The main divisiolls are illto elements, halogen compounds, oxides of hydrogen and metals, compounds of sulfur, seleniunl, and tellurium; the nitrogen, phosphorus, and arsenic group; and elements of tile fourth group and boron. There are appendices. including a very useful short account of the lnain lattice types. This descriptive part is not free from errors. a few of n-hicli may be mentioned. On page 194 it is said t h a t ammonia is “extensively” dissociated into its elemelits a t 200”; on page 224 i t is stated t h a t hydrogen chloride is “readily” soluble in benzene; and on page 283pyridine is describedas an “amine.” On page 282 it is stated that there are no groups conferring D positive charge on a JTerner nucleus, whilst a n esnmple of one is given on page 297; on page 310 it is said t h a t there are no compounds of cobalt n-ith one neutral group i n the nucleus, whilst one is formulated on the opposite page: an11 on page 301 Co(OH)2 is said t o be the only simple compound of trivalent cobalt. On pages :35S and 368 6he compound OF still appears. The use of the names “hypiodous acid” and ’.hypiodite” seems objectionable, since the Greek prefix may belong t o either “hypo” or ”hyper.” Several names are incorrectly given, e.g., “JIoh’s” for ”llohs’,” “Losenty” for “Lorentz,” “Bodlander” for “Bodenstein,” “Hnrbold” for “Hubold”; and the translation is sometimes defective, as when “Austernschalen” is rendered as “oetracite shales” and (‘gute Leuchtsteine” as “the best minerals,” on page 536. Yellow tungstic acid is said to be b.colloidal” (page 510), and the statements that there is no direct evidence for the doubled formula for hyposulfurous acid (page 546), t h a t the copper hydride precipitated by hypophosphite is CuH2 (page 714), and t h a t silver peroxide is precipitated by persulfate (page 594) are incorrect. On page 563 H’ ions should read OH’ ions; the Cas04 in superphosphate is now regarded as anhydrous and not “gypsum” (page 722); and recent work contradicts the formulae of the metal carbonyls given on pages 793-4. The reviewer failed t o find any mention of the important vanadium pentoxide catalyst in the manufacture of sulfur trioxide. The references t o four figures given in the preface are all incorrect. The above examples are given with the object of directing the attention of the editors t o some defects in the book which can be removed by more careful attention to the text, and not with the object of presenting an unfavorable criticism of the book as a iyhole. I t is not easy t o keep such a large amount of detailed information as is presented in a completely accurate form, but some of the errors should be put right in a new edition. ~

J. R. PARTIXGTON. Lange’s Handbook o j Chemistry. SORBERT ADOLPHL . 4 S G E , Editor. 5th edition. 1777 pp. 271 pp. of mathematical tables (compiled by Richard Stevens Burlington) 25 pp. of index. Sandusky, Ohio: Handbook Publishers, Inc., 1944. Price: $6.00. The latest edition of this valuable handbook consists of 1777 pages of technical inforniation and data of interest t o chemists, chemical engineers, and physicists. llatheniatical tables and formulas make up a special appendix of 271 pages. The index of 26 pages is thorough and informative. The general arrangement and subject matter are largely t h a t of the fourth edition, but neu- tables and revisions have added 174 new pages An important revision is in the table of physical constants of organic compounds. This section now includes 6507 compounds with Beilstein references giren n here possible. iimong several nen’ features are a Periodic Chart by Prof. Deming, and additional information on plastics. Properties and limitations of plastics are of increasing interest. Other new tables in the fifth edition are entitled: “Flammable Liquids.” “Flame Temperatures.” “Fluorescence of Chemicals, inerals‘, and Gems,” and “Water for Industrial Use.” A large table entitled “Compos on and Physical Properties of Alloys” is distinguished by being one of the fern- tables for n-hich no references are given. Reference might have been made t o the S a t i o n a l Metals Handbook and the Cast .lfcfols Haiidbook. Carbon steel and

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