8 Pring & Faiklie, Hydrocarbons and their Stability. 



According to data supplied by Berthelot,* O has the 

 value 2840 at ordinary temperatures, and the value at high 

 temperatures is seen from these results to be as follows ; — - 





1290 

 2100 

 2960 



3740 



It follows from these results that the mean specific 

 heat of carbon at these temperatures is higher than that 

 of graphite, and the difference increases rapidly with the 

 temperature. 



However, in the values given by Kunzf for carbon, 

 and by Weber :j: for graphite, the latter has the higher 

 value at all temperatures above 200°. This would lead 

 to the impossible relation that amorphous carbon is at 

 high temperatures more stable than graphite, so that 

 these values, obtained by direct measurement, cannot 

 apply at high temperatures. 



In the present work careful analysis of the gases was 

 made as described in earlier work.§ At about 2000°, no 

 marked influence was exerted by pressure on the amounts 

 of ethylene and acet}'lene produced. 



* Comp/es retidus [l?'?>o,),lO^, l\^A- 

 t Ann. Physik, 1904 [iv.], 14, 327. 

 X Ber., 1872, 5, 303. 

 § Trans. Chem. Soc. (191 1), 99, 1796. 



