Decomposition of Oxides and Salts by Chlorine. 229 



Sulphate of barytes 1*597 = 0*940 barytes. 

 Chloride of silver 1-998 = 0*493 chlorine. 

 This is rather more than 1 eq. of chlorine. 



I next endeavoured to ascertain the proportion of chloric 

 acid in this amount. For this purpose a portion of the same 

 liquid was precipitated by nitrate of silver, which gave the 

 quantity of chlorine combined as chloride. After separating 

 it from' this precipitate the liquid was treated with phospho- 

 rous acid, which naturally precipitated metallic silver and a 

 barytes salt, but also reduced the chloric acid. After heating 

 for some time, the precipitates were dissolved in nitric acid, 

 and the chloride of silver which formed, determined. 

 First precipitate of chloride of silver 4-992 = 1*182 chlorine. 

 Second precipitate 0*787 = 0*154 



This gives to 6 parts of chlorine as chloride, nearly 1 as 

 chlorate. The theory requires to 5 of chloride 1 of chlorate; 

 but part of the oxygen had probably escaped either free or 

 as hypochlorous acid. 



Having thus found that on treating barytes with chlorine 

 the decomposition takes place in so simple a manner, I next 

 endeavoured to find out whether the same laws would not 

 hold good in the case of the alkalies. Of these I first chose 

 potash, which was prepared by decomposing a solution of 

 pure sulphate of potash by barytes water. 



I. 4-051 of this solution gave 0*272 sulphate of potash = 

 01 07 potash, or 3-628 per cent. 18*819 were saturated with 

 chlorine, in the same manner as the barytes had been, and 

 gave, after reduction by ammonia and sulphurous acid, a pre- 

 cipitate of 3*314 chloride of silver = 0*818 chlorine. 



Calculated to the amount of potash, this gives to 590 potash 

 706*5 chlorine, instead of 443, which is 1 equivalent. 



II. 17*397 of the solution which was used for this determi- 

 nation gave 1*337 nitrate of potash = 0*6225 potash. 



19-027 gave 3-031 chloride of silver =.0*748 chlorine, or in 

 590 potash 647 chlorine, instead of 443. The average of these 

 two gives to 590 potash 677 chlorine, or to 2 eqs. of potash 

 3 of chlorine. 



This liquid possessed the smell of hypochlorous acid as well 

 as its bleaching properties. It contained no salt of hypochlo- 

 rous acid, that is to say, that all this acid contained in it 

 was in a free state, as was proved by the above-described re- 

 action with silver. 



A considerable quantity of chloric acid was contained in 

 this liquid, but was not determined, as it depended only on 

 the time allowed to elapse between the preparation of the 

 liquid and its being made use of for analysis. 



