Combination of Bodies xvith Oxt/gen. 337 



We have, therefore, for the heat evolved during the com- 

 bination of — 



One gramme oxygen with protoxide of tin . 4349 

 One gramme protoxide of tin with oxygen . 521 

 One litre oxygen with protoxide of tin . . 6249 



Copper ajid Oxygen, 



The copper employed was obtained by reducing the pure 

 oxide by means of hydrogen gas. The experiment was in all 

 respects similar to the two last. 



1. 2. 3. 



M 1-629 grm. 2-040 grms. 2-387 grms. 



T 8^-9 9--2 9''-6 



E 0°-3 0^-4 l°-4 



I 2°-310 2°-834 3^-258 



Ic 2°-302 2°-826 3°-272 



W 1603 grms. 1613grms. 1609 grms. 



V 117 grms. 1 1 7 grms. 1 1 7 grms. 



1. 2. .3. 



2427 2393 2362 



We have, therefore, for the heat evolved during the com- 

 bination of — 



One gramme oxygen with copper . 2394 

 One litre oxygen with copper . . . 3440 



Protoxide of Copper and Oxygen. 



The protoxide of copper was obtained by the action of glu- 

 cose at the boiling temperature upon a solution of sulphate of 

 copper to which caustic potash had been added. The oxide 

 thus obtained was dried, first in the air at a temperature not 

 exceeding 100°, and afterwards at a low red heat in a current of 

 dry carbonic acid gas. It was burned in the usual manner ; 

 but the results in different trials did not agree well with one 

 another, and the combustion proceeded so slowly that nearly 

 half an hour was occupied in each experiment. It was assumed 

 in correcting for the cooling influence of the air, that the ap- 

 jniratus was at the maximum temperature during twenty-two 

 minutes. 



M 

 T 

 E 

 I 



Ic 

 W 

 V 



Phil. Mag. S. 3. Vol. 32. No. 216. May 1848!' Z 



