551 



Article XVII. 



On the Anhydrous Sulphate of Ammonia. By Heinrich Rose. 



[From Poggendorif's Annalen, vol. xlix. p. 183.] 



In attempting to precipitate the excess of sulphuric acid from 

 a solution of anhydrous sulphate of ammonia by means of car- 

 bonate of barytes, I succeeded in obtaining crystals of consider- 

 able size from the fluid separated from the sulphate and excess 

 of carbonate of barytes ; these crystals I took for anhydrous sul- 

 phate of ammonia ; having obtained only a small quantity I did 

 not subject them to analysis, but employed for this purpose the 

 indistinctly crystallized mass, which remained with these crystals 

 after evaporation over sulphuric acid. I found in them only 

 67'47 per cent, of sulphuric acid instead of 70'03, which, ac- 

 cording to theory, the anhydrous sulphate of ammonia should 

 contain*. 



I have since separated, in the above-described manner, the 

 excess of acid from larger portions of the anhydrous sulphate of 

 ammonia, and have obtained a greater quantity of these crystals. 

 At the same time I investigated more accurately the action of 

 water on this salt, which had been carefully prepared, and was 

 perfectly neutral. After precipitating the excess of acid by car- 

 bonate of barytes, I satisfied myself that the solution had pre- 

 cisely the same properties as the salt obtained by treating an- 

 hydrous ammonia with anhydrous sulphuric acid. I found 

 also, what I had not been before able to decide with certainty, 

 on account of the small quantity of the salt employed, that the 

 solutions do not contain one salt, but two different salts, pos- 

 sessing very singular properties, and remarkable as to their com- 

 positionf. 



I have also submitted the properties and composition of neu- 

 tral anhydrous sulphate of ammonia to a fresh examination, and 

 have ascertained some facts which will complete my former in- 

 vestigations, 1 have called this salt sulphat-ammon J, for reasons 

 formerly explained ; the two salts obtained from its aqueous 



* Poggendorff's Annalen, Bd. 47, S. 474. 

 t PoggciulorfT's Annuhm, Hd. 32, S. 81. 

 I Ebeiidaselbst, lid. 37, S. 475. 



