DIAZOBENZENE NITRATE. 471 



-f 242-8 CaL (gaseous mercury); or, for 1 kgm., 706 Cal., or 

 663 Cal. 



3. The reduced volume of the gases = 67 litres, or 89*2 litres 

 (gaseous mercury) ; or, for 1 kgm., 183 litres, or 244 litres. 



4. The permanent pressure - - ' with the usual reserva- 

 tion. 



K m, .* A , 6830 atm. 



5. The theoretical pressure = 



n Oil 



It is very nearly the same as that of pure fulminate. Potas- 

 sium chloride lessens the effects of the shock ; but potassium 

 chlorate renders the mixture very sensitive. Accidents, there- 

 fore, frequently ocour in factories when this mixture is being 

 prepared. 



5. DIAZOBENZENE NITRATE. 



1. The properties and analysis of this body, as well as the 

 study of its explosive decomposition, have been set forth (p. 291). 

 We shall only repeat the following figures. 



The formula is 



C 6 H 4 N 2 NO 3 H = 167 grms. 



2. The formation from the elements absorbs 47'4 Cal. 



3. The total combustion 



2C 6 H 4 N 2 N0 3 H + 230 = 12C0 2 + 5H 2 + 6N, 



liberates -f 782 '9 Cal. at constant pressure (liquid water). No 

 attempt has been made to study the effects of the combustion of 

 diazobenzene by the oxidising bodies. The mixture with these 

 bodies would, moreover, present great difficulties, owing to the 

 sensitiveness of the dry substance and its immediate decomposi- 

 tion by water. 



4. The explosive decomposition yields complex products, 

 which vary with the conditions. They have been noticed 

 (p. 293). 



5. Heat liberated. The decomposition having been effected 

 by the incandescence of a platinum wire, at a low density of 

 charge, it liberated -f 114'8 Cal. at constant volume for 1 equiv., 

 or 687'7 Cal. for 1 kgm. 



6. Gaseous volume. There was produced at the same time 

 136'6 litres of gas (reduced volume) for 1 equiv., or 817'7 litres 

 for 1 kgm. 



7. The theoretical pressure = - 7- It is higher than 



n O'Oo 



that of the fulminate at the unit of weight, and approaches that 

 of the most powerful substances. 



