410 SALTS 



So that the oxide amounts to . . 118 



And the acid to 24- 



Now, J =3*5, and ~\~= 17> which approaches 

 very nearly to 16'88, the quantity of silver con- 

 tained in the salt which I examined. 

 Arseriate, 5. Arseniate of silver. When solutions of 

 nitrate of silver and arseniate of soda are mixed 

 together in the atomic proportions, a flesh co- 

 loured precipitate falls in large flocks. This 

 precipitate is arseniate of silver ; it is tasteless, 

 or nearly so, and is insoluble in water. When 

 dried it becomes reddish brown ; when heated to 

 redness it becomes nearly black ; and 34'4 

 grains, when thus treated, lost 0*5 grain of wa- 

 ter, which was obviously merely lodged me- 

 chanically in the powder. By this treatment the 

 powder assumes nearly a black colour. 



43 grains of anhydrous nitrate of silver were 

 dissolved in water, and mixed with a solution of 

 41 '5 grains of the crystals of arseniate of soda : 

 the flesh red powder which precipitated being 

 collected, washed, and dried on the filter, weighed 

 37*75 grains. Ammonia being poured into the 

 residual liquid an additional flesh red precipitate 

 fell, which weighed, when dry, 2 grains ; so 

 that the whole arseniate of silver obtained from 

 43 grains of nitrate of silver was 39*7^ grains ; 

 which, by exposure to a red heat, was reduced 

 to 39*22 grains. As it contained all the silver 



