COMPOSITION OF SULPHATES. 



159 



potash, and 50*24 of acid, must enter into the composition 

 of 100 parts of the nitrate. 



Exp. 5. The object of this, as of the former experiment, Proportions of 

 was to ascertain, whether the base and acid in muriate of "^j^ 60 

 potash were in the proportions commonly admitted. For 

 this purpose I employed the means I have just described; 

 and, as it would be superfluous to repeat the particulars, 

 1 shall confine myself to the results. 



100 gr. of dry muriate of potash, treated as in the 

 preceding experiment, produced 607 gr. of crude alum; 

 which, after being refined, left but 592 gr. : a result 6517 base an<I 

 proving incontestably, that 100 parts of muriate of potash S4 8a u<;id * 

 contain 65*17 of base and 34*83 of acid. This experiment, 

 which, like the preceding, was several times repeated, 

 always afforded me similar results. 



From the experiments that have been described, it General con. 



e ,, elusions, 



to Hows, 



1. That 100 parts of sulphate of potash contain 57*71 

 of potash and 42*29 of acid, which, from the state of con- 

 centration in which it exists in this sulphate, are equivalent „ 

 to 60 parts at 66° [sp. gr. 1*848]. 



2. That to form 100 parts of alum requires 42*77 

 of sulphuric acid at 66°, instead of 30 or 31, the quantity 

 generally admitted; 11*01 of potash; and 10*50 of alumine: 

 a quantity equal to what was found by Vauquelin. 



3. That 100 parts .of very pure alum contain 19*08 of 

 sulphate of potash, 30*g2 of sulphate of alumine, and 50 of 

 water of crystallization. 



4. That 49*76 parts of potash and 50*24 of acid enter 

 into the composition of nitrate of potash. 



5. That 100 parts of muriate of potash are composed of 

 65*17 potash, and 3483 muriatic acid. 



6. That it is certain potash purified with alcohol contains 

 more than a fourth of its weight of water, since, from the 

 experiments that have been related, 27*5 per cent may be 

 obtained from it. 



7. Lastly, that by means of sulphate of alumine, with 

 the simple base and crystallized, we may in future, in the 

 analysis of the substances of either of the three kingdoms, 

 detect the smallest quantity* of potash contained *0 either: 



the 



