chlorine, &c., Berthelot's ' Calorimétrie pratique ' may be consulted with advantage.
In order to make the harmony of the operation and the calculation clearer, I cite an example (taken from the work referred to) :
Combustion of carbon (charcoal purified by chlorine at a red heat).
0*487 gm. charcoal ; ash, 0*0028 gm. ; real carbon, 0*4842 gm.
Preliminary period ; temperatures read :
��After minute 17*360°
After the 1st „ 17-360°
2nd „ 17*360°
Combustion :
After the 5th minute 18-500° 6th „ 18-782°
Final period :
After the 9th minute 18*810° „ 10th „ 18-802° „ 11th „ 18-795°
��After the 3rd minute 17*360° 4th „ 17-360°
��»»
��After the 7th minute 18-820° 8th „ 18-818°
��After the 12th minute 18-785° „ 13th „ 18-775° „ 14th „ 18*770°
Rise in temperature :
Uncorrected : 18-818° - 17-360° = 1-458° Corrected: 1-484°
Water-equivalent of the calorimeter, bomb, compressed oxygen,
thermometer, &c 2,398*4 gm.
Weight of nitric acid formed .... 0*0173 gm.
Total heat observed .... 3,559*2 cal. : of which for the combustion of the iron spiral . 22-4 ) 26 . 3 , for the formation of dilute nitric acid . 3*9 '
for the combustion of the carbon . . 3,532*9 cal.
1 gram of carbon evolves 8,136*6 „
12 grams (one gram atomic weight) evolves 97*64 Cal.