SULPHATE OF BABYTA IN ACID SOLUTIONS. 



91 



Although the quantity of salt employed in this case was 

 capable of producing 7.13 grs. of sulphate of baryta, still, 

 after twenty-four hours there was no precipitate produced in 

 jars No. 9 and 10, and in order to obtain a precipitate in all 

 the jars composing a series, I was obliged to employ quan- 

 tities of salts of baryta and potash, capable of producing 

 10.0 grs. of sulphate of baryta. 



In order to confirm the results given in Table No. 3, the 

 precipitates formed in the above series were collected, and 

 their weight determined. 



TABLE No. 6. 



These results prove that 1000 grs. of nitric acid sp.gr. 1.167, 

 are able to dissolve about 2 grs. of sulphate of baryta. 



ON THE INFLUENCE EXERCISED BY AN EXCESS OP 

 PRECIPITANT. 



As it is generally admitted that an excess of precipitant 

 increases the chances of obtaining the total precipitation of 

 the sulphate in solution, I thought it useful to make a series 

 of experiments to ascertain if these views were correct, and 

 it will be seen, by comparing the results given below with 

 those of Table No. 2, in which equivalent quantities were 

 used, that such is not the case, since the results in the two 

 tables are identical. 



