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CHAPTER VII. 



HEAT OF FORMATION OF NITROGEN SULPHIDE. 1 



1. NITROGEN SULPHIDE. 



1. THIS body is a solid, crystallised, yellow, explosive substance, 

 expressed by the formula NS, and by the equivalent 46. It is 

 prepared by the action of ammoniacal gas upon sulphur 

 chloride, dissolved in carbon disulphide. 2 



The specimen used in these experiments gave upon analysis 



Found. Calculated. 



N 69-64 69-56 



S 30-41 30-44 



H ... ... 0-01 



2. Nitrogen sulphide is stable at the ordinary temperature. 

 It is preserved without alteration both in dry and in damp air. 

 It may be moistened and then dried at 50 without any appreci- 

 able alteration, even should these operations be repeated several 

 times. 



Its density at 15 was found to be equal to 2'22. 



Nitrogen sulphide detonates with violence upon being struck 

 with a hammer, but its sensitiveness to this shock is less than 

 that of mercury fulminate. 



On being heated it explodes at 207 and above this heat. Its 

 decomposition is, however, much slower than that of mercury 

 fulminate or diazobenzol nitrate. We may remark that this 

 temperature of conflagration is near that of the combustion 

 of sulphur freely exposed to air. 



3. Heat of detonation. The decomposition of the nitrogen 

 sulphide was provoked in a pure dry atmosphere of nitrogen, in 

 a bomb lined with platinum. 



It was ignited by means of a very fine metallic wire, plunged 

 nto the substance and heated to incandescence by means of ail 



1 This study was made jointly with M. Vieille. 



2 Fordoz et Gelis, " Annales de Chimie et de Physique," 3 serie, torn, 

 xxxii. p. 385. 



