252 HYDROGENATED COMPOUNDS OF NITROGEN. 



In the same way, it was found that hydrochloric acid gas in 

 excess, and also boron fluoride, do not determine the decompo- 

 sition of hydroxylamine, notwithstanding their avidity for the 

 water which might be formed at its expense. But this relative 

 stability is explained by the preceding considerations, i.e. in 

 proportion to the formation of the saline compounds. 



But on the contrary, hydroxylamine, when free or dissolved 

 in a very small quantity of water, i.e. possessed of all its energy, 

 manifests a strong tendency to spontaneous destruction, and 

 this destruction works in a way that gives off the more heat the 

 more suddenly it is effected. 



14. To recapitulate these various processes of decomposition. 



(1) In the most simple decomposition 



NH 3 dissolved = N -f H + H 2 -f water would liberate 



+ 50-0. 



But this sudden reaction has not been observed ; the nascent 

 hydrogen remained completely associated with the nitrogen 

 in these conditions, and it forms ammonia, a formation ac- 

 companied by a second liberation of heat. 



(2) In a sudden reaction we see the transformation of a third 

 of the nitrogen into ammonia, as follows 



3NH 3 dilute = JSTH 3 dilute + 2N + 3H 2 O, 



a reaction which gives off in addition -f- 7, or altogether +57. 



We observe also the absence of the compound NH, which one 

 would think ought to appear under these conditions. Though 

 sought for particularly, no trace of it was obtained. 



The formation of water itself, which it would seem a priori 

 ought to be effected in preference, preponderates only in the 

 sudden reaction brought about by potash; probably by reason 

 of the tendency of this alkali to form hydrates with liberation 

 of heat. Thus the slightest influence determines the manner 

 in which this unstable compound is destroyed. 



(3) On the contrary, in the spontaneous decomposition of 

 hydroxylamine, such as takes place in the presence of am- 

 moniacal gas, we see chiefly nitrogen monoxide appear, with less 

 liberation of heat ( + 484 X 2 instead of + 57 X 2, all the 

 substances being supposed to be in solution). 



15. Constitution. This last decomposition, effected upon two 

 molecules of hydroxylamine, one of which abstracts the hydro- 

 gen from the other, recalls the resolution of an aldehyde into 

 the corresponding alcohol (or rather carburet) and acid. We 

 may here remark that the slow decomposition of hydroxylamine 

 is at the same time that which develops least heat and which is 

 produced in preference, under conditions in which most care is 

 taken. Moreover, it takes place at exactly the same temperature 

 as the decomposition that gives off the most heat. But these 



