W. G. Mixter — Carbon and its Heat of Combustion. 439 



According to Thomsen* the thermal effect of the formation 

 from its elements of Ag 2 N 2 6 and solution in water is 46,600 

 calories. From which we find that 1 mlg. of silver dissolved 

 corresponds to 0*216 c . The solution from the interior of the 

 bomb after an explosion in no instance reacted acid to ordinary 

 litmus paper, showing that the nitric acid was mostly taken up 

 by the silver. In experiment 4, 85*4 mlgs. of silver were 

 found in rinsings, showing 18*4° were due to the oxidation of 

 nitrogen and solution of silver. 



Experiment 5 . — Carbon 1*3054, hydrogen 0*0004, iron 0-0385, 

 silver dissolved 0*0726, oxygen 10*2, water and water equiva- 



Temperature interval. 



22*083 — 18*958 + 0-021 = 3*146° 



Heat observed, 3302*2X3*146 = 10388*T 

 " of oxidation of iron — 6l*6 c 



" " hydrogen — 13*6 C 



" formation of silver nitrate — 15*7 C 



ent 3302*2 



grams. 



Minutes. 



Temperature. 







18*958 



1 



18-958 



2 



18*958 



3 



21*8 



4 



22*079 



5 



22-092 



6 



22*088 



7 



22*083 



8 



23*077 



9 



22*073 



10 



22*067 



11 



22*062 



12 



22*055 



13 



22*051 



10297*8< 

 For 1 gram of carbon 7888*8 ( 



Experiment 6.— Carbon 1*3277, hydrogen 0*0004, iron 0*040, 

 silver dissolved 0*0918, oxygen 9*7, water and water equivalent 

 3253*9 grams. 



Minutes. Temperature. Temperature interval. 



18*894 



1 18*896 22*135 — 18*9 + 0*014= 3-249° 



2 18-898 



3 18*900 Heat observed, 3253*9X3*249 = 10572* c 



4 21*9 " of oxidation of iron — 64* c 



5 22*129 " " " hydrogen — 13*6 C 



6 22-139 " formation of silver nitrate — 19*8 C 



7 22*137 



8 22-135 10474-6° 



9 22-131 For 1 gram of carbon 7889'4 C 



10 22*127 The gas in the bomb after the calori- 



11 22*124 metric test was transferred to a gas 



12 22*121 holder containing a solution of caustic 



13 22*117 potash and was left several hours to 



14 22-114 ensure the complete absorption of car- 



15 22*111 bondioxide. It was then passed into 



16 22*108 a solution of barium hydroxide and 

 * Thermo-Chem. Untersuchen, iii, p. 282. 



