OF ZINC. 339 



zinc ; luid the quantity been 120 grains, it is 

 obvious that its constituents would have been 



1 atom oxalic acid . 4-5 



1 atom oxide of zinc . 5-25 



2 atoms water 2-25 



12-0 



Tiie loss of the two grains was owing to the fil- 

 ter on which the oxalate of zinc was collected. 



10. Tartrate of zinc. This is a soft white 

 tasteless powder like chalk. It is anhydrous; 

 for 13v5 grains of it being calcined in a platinum 

 crucible left 5'25 grains of oxide of zinc. Hence, 

 its constituents are 



1 atom tartaric acid . 8-25 



1 atom oxide of zinc . 5*25 



J3-5 



The salts of zinc, as far as we can judge from 

 the preceding list, vary a good deal in their wa- 

 ter of crystallization, though the quantity is ra- 

 ther small, eight atoms of water being the 

 greatest number found in any salt hitherto ana- 

 lyzed. Carbonate, chromate, and tartrate, are 

 anhydrous hydrous carbonate contains 1 atom 

 water phosphate and oxalate 2 atoms sul- 

 phate, from a hot solution, 3 biphosphate 4 

 nitrate 6 sulphate and acetate 7 andarseniate 



