530 Mixter — Thermochemistry and the Periodic Law. 



Most of the heat equivalents of the sixth group were found 

 by the writer,* and he would call attention to two of them, 

 namely : Na 2 + WO, = 94' 7 Cal. and Na 2 + U0 3 = 961 

 Cal. The first was derived by the heat of combustion of 98 



Fig. 6. 



320 



i2Na+S+40 



NajO + RO, 



20 



Cr 



Fig. 6. Diagram of Group VI. The thermochemistry of sulphur, selenium 

 and tellurium is shown by heavy lines, that of the other elements of the 

 group by light lines. 



* Chromium and tungsten, this Journal, xxvi, 125, 1908. Molybdenum, 

 selenium and tellurium, ibid., xxix, 488, 1910. Uranium, ibid., xxxiv, 141, 

 1912, and Zeitschr. anorg. Chem., lxxviii, 22, 1912. 



