General and physical chemistry

1920 Journal of the Chemical Society Abstracts  
Spectra ALFRED LARTIGUE (Compt. reqzd., 191 9 , 169, 914-915).-1n place of the general formula 1 0 8 /~= N , ( l / p~-l / y 2 ) waves per cm., the author proposes to use the formula h,=(4 x 1 O 8 / S 0 ) [ 2 / p + l / m -l / ( m + 2 p ) ] Angstroms, where m = q -p . I View Article Online GENERAL AND PHYSICAL CHEMISTRY. ii. 3 tho use of a irietal shutter pierced with a slit. and travelling iii front of t,he sensitive plate with a velocity such that, during the rotation of the crystal, the
more » ... crystal, the reflected ray passes continuously through the slit. W. G. Relative Brightness of Dark Radiation at the Melting Points of Gold and Palladium. FR. HOFFMANN aud W. MEISSNER ( A nn. Physak, 1919, [iv], 60, 201--232).-The relative brightness of the dark radiation a t t h e melting points of gold and palladium has been measured by two different methods: first, by use of a n improved hollow radiator constructed on t h e Lummer-Kurlbaum principle, whereby the melting point was determined inside the radiator by the wire method; secondly, by use of a hollow radiator which was immersed in the molten metal. The measurements of brightness were made with a Konig-Martens spectrophotoineter. The relative brightness a t t h e melting points of gold and palladium is expressed by 81.5 at the wave-length of 0 . 6 5 6 3~. The palladium used had the same melting point as that used by Day and Sosman in the gas thermometric measurements. Palladium prepared by repeated precipitation of the ammonium double chloride by means of mercury cyanide gave a very constant melting point, and would serve excellently as a fixed point for temperature determinations. Using c=14,300 as the radiation constant and 1063O as the melting point of gold, it is found that l 5 5 7 O is t h e melting point of palladium. This value is about 8 O higher than Day and Sosman's figure, 1549.2O. J. F. S. It is shown t h a t Konigsberger's law, t h a t the breadth of the 1-2
doi:10.1039/ca9201805001 fatcat:kxtnddf6ybdvfbxogr254r6lmu