PROFESSOR ROSCOE’S RESEARCHES ON VANADIUM. 
QOI 
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stable, Vo 0 5 liberating three molecules of C0 2 when fused with carbonate of soda, but 
forming a monobasic (meta)salt when boiled with a solution of alkaline carbonate. 
(3) That as the majority of the naturally occurring vanadates are tribasic compounds, 
we may assume that these have been produced at a high temperature. 
(4) That in aqueous solutions the soluble pyrovanadates are easily decomposed by 
carbonic acid into an alkaline carbonate and a monobasic or metavanadate. 
Hence the order of stability of the different vanadates at the ordinary temperatures 
is as follows : — 
(1) Monobasic or metavanadates. 
(2) Tetrabasic or pyrovanadates. 
(3) Tribasic or orthovanadates. 
In the phosphorus series the order of stability is (as is well known) exactly the 
reverse of this, the tribasic phosphoric acid and soluble orthophosphates being most 
stable, and being formed from the other two classes of acids and soluble salts, either 
by ebullition alone or in presence of weak acids. 
I have much pleasure in acknowledging the able assistance which I have received 
from Messrs. CElhofer and Tinkelstein in carrying out the above investigation. 
