1821.] Action of Chlorides and Water, flfll? 



Article IV, 



On the Action of Chlorides and Water. 

 By Richard Phillips, FRSE. FLS. &c. 



Different opinions appear to be entertained by chemists of 

 the greatest eminence and experience as to the changes effected • 

 on those chlorides that are soluble in water by solution in it^. 

 On this account I propose to state such opinions as I have- 

 found detailed on the subject, and I shall endeavour to collects 

 the evidence which has been adduced in support of the different, 

 views entertained. 



The question to be solved may be thus stated : When a chlo- 

 ride is dissolved in water, does it remain a chloride, or is it by 

 decomposing water converted into a muriate ? It is further to be : 

 considered, whether the same explanation will apply to all the.; 

 aqueous solutions of chlorides. 



With respect to the non-metaUic chlorides, it is to be observed^ 

 that one of them, viz. chloride of azote, is insoluble in water, , 

 and consequently no change is effected in the properties of either 

 compound. The chlorides of phosphorus and of sulphur on the^ 

 other hand act with great energy on water, and offer incon-*f 

 trovertible evidence that water in these cases suffers decompo- 

 sition, for the products are such as do not combine with eacfc 

 other, but exist in a state of mixture in the water, each possess»y 

 its peculiar properties. Thus when chloride of phosphorus and 

 water undergo mutual action, the oxygen of the water fonooSr 

 pjiosphorous acid with the phosphorus, and the hydrogen unites 

 with the chlorine to form muriatic acid. The perchloride of 

 phosphorus effecting similar decomposition yields phosphoric 

 and muriatic acids ; and when chloride of sulphur and water 

 undergo mutual decomposition, there are produced sulphurous, : 

 sulphuric, and muriatic acids. 



Sir H. Davy (Phil. Trans. 1810) observes, that " when water, 

 is added in certain quantities to Libavius's liquor, a solid crystal-* 

 line mass is obtained, from which oxide of tin and muriate of* 

 ammonia can be obtained by ammonia. In this case, the oxy- 

 gen may be conceived to be supplied to the tin, hydrogen to the 

 oxymuriatic acid." In the Phil. Trans, for 1810, he states more^ 

 distinctly that Libavius's liquor is " converted into a muriate-^ 

 by water." 



In his Elements of Chemical Philosophy, Sir H. Davy. ha» v 

 been, in many instances, quite explicit on this point ; and hia^' 

 opinions are favourable to the idea that chlorides become 

 muriates by being dissolved in water. Thus he states that the^- 

 perchloride of iron " acts with violence upon water, and format 

 a solution of red muriate of iron;" and he observes that thCv. 

 protomuriate ** forms a solution of green muriate of iron by it»4 

 action upon water." 



