1976
JOURNAL OF CHEMICAL EDUCATION
AUGUST,1930
Prize of the Royal Society of Edinburgh. is announced in The Chemical Age, that SIR f i o w s s o ~Sm E. A. S ~ ~ P B V - S C M F E RJAMES , C. IRVXNE, Princip,al and ViceF.R.S.. the president, occupied the chair Chancellor of St. Andrews' University, is and made the presentation, after which among those nominated by MR. BALDWIN, Professor Bohr delivered a n address on as Chancellor of the University of Cam"Philosophical Aspects of the Atomic bridge, far the receipt of honorary doctorTheory." ates. Dr. I ~ n ise a member of the staR of foreign editors of the JOURNAL oa E~UCATION. St. Andrews' University, Scotland. It CHEMICAL
Raman Eflect. The amount of light that is scattered by a fluid without change in wave-length increases enormously when the substance is in the critical state. Raman himself suggested that an analogous increase occurred with the modified secondary radiation from carbon dioxide, but W. H. Martin afterward obtained negative results with a mixture of phenol and water (see Nature, Oct. 6, 1928, p. 506). The question is important and has now again been attacked by S. L. Ziemecki and K. NarkiewiuJodko, in Warsaw. Their work, which is outlined in Die Natum~ssenschaften for Nov. 8th. was done with the criticalmixture of isobutyric acid and water at 24°C.. with a powerful mercury arc of special construction for the primary source. The Raman lines due t o the acid were found t o be present in the scattered light, but their intensity was certainlv not more than some 30 Per cent above normal, and even this apparent increase may have been due t o a heavy continuous background in the secondary specout that this furnishes an experimental proof that the Raman trum. They . point . radiation is not cohrrmt 'l'ao f t ~ n h cpapers r on the Raman cHect havc :also sppparrd in recent issues of thr Indzan Jonrnal of PRyrirr. the third number of thr current volume containing an account of an extended series gf observations on modified radiation, by S. Venkateswaran and A. S. Ganesan, and the fourth number a useful summary and bibliography of 150 papers on the subject, by Dr. Ganesan.-Nature ~
The Freezing Point of Sulfuric Acid and Strength of Solution. The freezing point of sulfuric acid presents a very interesting study, although the information given here is by no means new. The oil of vitriol of commerce is known as 66' acid, that is, i t tests 66" B a u m G t h e equivalent of 1835 in specific gravity. At this strength it freezes a t minus 29°F. (-29'F.). Sulfuric acid is extremely hygroscopic, absorbing moisture from the atmosphere with great rapidity. At first a very slight quantity of moisture will raise the freezing point very rapidly until a t 60- Baumk the freezing point will be as high as +lZDF. Further accumulation of moisture depresses the freezing point to minus 59'F. (-59'F.) when the acid tests 54' Bawnk. A further increase in moisture serves to again raise the freezing point to minus 14'F. (-14°F.) when acid tests 46" Baume. At this point sulfuric acid practically ceases t o be hygroscopic. When the moisture content is increased t o the point where the Baumb reading From this is 33" Baum6, the freezing point is found to be minus 97'F. (-97'F.). point the addition of water raises the freezing point rapidly a t first and more slowly toward the end, until the point is reached where the acid content is theoretically zero, when the freezing point is, of course, +32'F., the freezing point of water.-Science Educ.
