54 OXYGEN AND HYDROGEN GASES. 



As zinc combines with oxygen in only one 

 proportion, it is reasonable to conclude that the 

 oxide is a compound of 1 atom zinc and 1 atom 

 oxygen. If this supposition be admitted, the 

 atom of zinc is, obviously 4^ times heavier than 

 the atom of oxygen. And if we represent the 

 atomic weight of oxygen by unity, then the 

 atomic weight of zinc will be 4*25 and the in- 

 tegrant particle of oxide of zinc will weigh 

 5*25 ; or in other words, 5'25 of oxide of zinc 

 will just saturate an integrant particle of any 

 acid with which it is capable of combining. 

 The law holds with all acids ; but I shall at 

 present verify it only by referring to three acids ; 

 namely, the sulphuric, carbonic, and arsenic 

 acids. It will be shown in the 5th, 1st, and 7th 

 sections of the sixth chapter of this work, that 

 the atomic weights of these acids are as follows : 



Sulphuric acid . 5 

 Carbonic acid . 2-75 

 Arsenic acid . 7*75 



Now, 5*25 of oxide of zinc will just saturate 

 5 of sulphuric acid, 2'75 of carbonic acid, and 

 7*75 of arsenic acid; or in other words, the 

 sulphate, carbonate, and arseniate of zinc, sup- 

 posing them anhydrous, are composed as follows : 



]. SULPHATE OF ZINC. 



Sulphuric acid . 5 

 Oxide of zinc 5-25 



