430 ZINC, CADMIUM, LEAD, c. 



silver may be deduced. It was there mentioned, 

 5 that when solutions of 21 %5 grains of nitrate of 

 silver and 7%5 grains of decrepitated common 

 salt are mixed together, a curdy precipitate falls, 

 and the residual liquid is neither affected by ni- 

 trate of silver nor common salt. It is evident 

 from this experiment, that the silver in 21*5 

 grains of nitrate of silver, and the chlorine in 7%5 

 grains of chloride of sodium, just saturate each 

 other. 



Now, 7-5 grains of chloride of sodium con- 

 tain exactly 4%5 grains of chlorine. And, if 

 21 %5 grains of nitrate of silver be cautiously 

 heated to redness, the salt will be decomposed, 

 the acid driven off, and the oxide reduced ; the 

 weight of silver remaining will be exactly (or at 

 least very nearly) 13 '75 grains. It is obvious 

 from this, that the chloride of silver, formed by 

 the mutual decomposition of 21/5 nitrate of sil- 

 ver and 7*5 chloride of sodium, must consist 

 of 



Silver . . . 13-?5 



Chlorine . 4-5 



18-25 



Accordingly, when the precipitate is collected 

 without loss, and after being well washed and 

 dried is exposed to a heat sufficiently high to fuse 

 it, the weight is exactly 18 '5 grains. 



