170 CALORIFIC POWER OF FUELS. 



uses 8 times its weight of oxygen and generates 9 times the 

 quantity of water. 

 Then 



2 9 = 6727 C. 

 9 X 0.479 



Bunsen and Sainte-Claire Deville showed that the highest 

 temperature actually obtained is 2500 C., which may be in- 

 creased to 2850 C. by a pressure of 10 atmospheres. 



The presence of nitrogen modifies the result materially. 

 The quantity of oxygen required, obtained from air, would 

 introduce 26.78 parts of nitrogen, the specific heat of which 

 is 0.244. The equation would then be 



29000 6 C 



9 X 0.479 + 26.78 X 0.244 " 



Bunsen's maximum temperature actually reached was 

 1800 C. 



2. Carbon. Carbon burnt to carbonic oxide consumes 

 1.33 parts of oxygen, forms 2.33 parts of carbonic oxide, and 

 if burnt in air, introduces 4.46 parts of nitrogen. The specific 

 heat of carbonic oxide is 0.245 an d of nitrogen 0.244, a $ 

 before. The heat units generated are 2435. 



For combustion in oxygen the equation would be 



2435 



2.33 X 0.245 

 In air it would be 



-=I 4 62C. 



2.33 X 0.245+4.46 X 0.244 

 The latter temperature is about the same as that actually 

 observed, and shows that but little dissociation occurs. 

 Owing to the non-volatility of carbon no flame is produced, 

 only an incandescence. The flame we ordinarily see on in- 

 candescent carbon is from the burning of carbonic oxide. 

 Carbon burnt to carbon dioxide can be treated similarly; also 

 carbonic oxide burnt to carbon dioxide. 



