NATURE OF THE BLEACHING COMPOUNDS OF CHLORINE. 287 



This cloud is sometimes deposited in oily drops, which have all the pro- 

 perties of chloride of azote ; it is however more frequently carried off 

 in the state of vapour by the gas which continues to be disengaged. 



This chloride of azote is very easily produced, especially when there 

 is suspended in dilute chlorous acid a fragment of an ammoniacal salt, 

 as for example of sulphate, phosphate, &c. The decomposition then 

 goes on very slowly, but a small quantity of gas is absorbed, which is 

 in this case a mixture of chlorine and azote, and not of pure azote, and 

 there is formed at the same time a notable quantity of chloride of azote. 

 This process appears to me the most convenient that can be employed 

 for the preparation of this substance. A very small quantity of it how- 

 ever is obtained, if, instead of placing the fragment of salt in chlorous 

 acid, it is mixed with the acid after being dissolved in water. The ac- 

 tion then occurring instantaneously and rapidly on the whole mass, and 

 no chloride of azote is obtained ; or at any rate, if this compound is 

 formed, it is carried off by the brisk effervescence which occurs in this 

 case. 



It is almost useless to say, that no chloride of azote is obtained when 

 concentrated chlorous acid is poured into concentrated ammonia. The 

 action is then veiy rapid ; it is accompanied with so great a disengage- 

 ment of chlorine and so abundant an emission of gas, that it takes place 

 with a sort of detonation. 



This action is still more vivid when bubbles of ammoniacal gas are 

 added to a few drops of chlorous acid in a receiver over mercury. There 

 is not only a great disengagement of heat, but an emission of yellow 

 light, and the upper part of the receiver contains a mixture of azote 

 and chlorine gas. 



It will be readily perceived that in all these circumstances it is prin- 

 cipally by the oxygen of chlorous acid that the decomposition of the 

 ammonia is effected, and that the chlorine and azote, simultaneously set 

 free, sometimes coalesce to form chloride of azote, and are at others 

 disengaged in a state of aeriform existence, according to circumstances. 



The two elements of the compound combustible are, on the contrary, 

 completely burnt, in great measure by the oxygen when chlorous acid 

 is made to act upon gaseous hydrogenated combinations of phosphorus, 

 arsenic, and of sulphur. Phosphuretted hydrogen, introduced into a 

 small receiver containing a few drops of chlorous acid, burns on coming 

 into contact with this liquid. There are produced phosphoric acid and 

 chloride of phosphorus, which are ultimately decomposed into hydro- 

 chloric and phosphoric acid. No uncombined phosphorus is observed, 

 but pure chlorine is collected in the upper part of the bottle. 



The same phfenomena occur with arseniurettcd hydrogen. The 

 combustion takes place with a flame of a blue tint. In tlie place of 

 chlorous acid are found arsenic and hydrochloric acids, and tlie upper 



