508 FLUATES. 



acid, and an oxidated combustible or metallic base ; if therefore die 

 fluoric acid contains one proportion of oxygen 8, the base will be ex- 

 pressed by 2.* 



EQUIVALENT OF FLUO-SILICIC ACID. 



Reasoning upon the per centage of silica in fluoric acid gas, (61.4 

 John Davy,) its constitution is inferred to be, 



1 proportion of fluoric acid, =10 



1 " silica, 16 



26, which would ap- 

 pear to be its equivalent number. f 



EQUIVALENT OF FLUO-BORIC ACID. 



Upon the same authority, it is stated at 



1 proportion fluoric acid, 10 



I " boracic acid, - 24 



34 



FLUATES. 



General characters. 



Upon the supposition that they are compounds of fluoric acid and 

 oxidated bases, rather than of fluorine and bases, or that they are 

 fluates and not fluorides. 



1 . Formed synthetically, by the union of pure fluoric acid with 

 the base, or by double exchange of a solution of an alkaline fluate 

 with the intended base combined with some acid in a soluble form. 



2. The neutral fluates with fixed bases, fusible at high temperatures, 

 and in close vessels ; if dry, not decomposed by any degree of heat. 



3. Fluates of alkalies and alkaline earths not decomposed by heat, 

 even when aided by the affinity of combustibles. 



4. No anhydrous acid except the vitreous boracic decomposes them 

 by heat alone, and this only by combining at the moment of decom- 

 position with the fluoric acid. 



5. Decomposed by being moderately heated with sulphuric, muri- 

 atic, phosphoric and arsenic acids. 



* If the fluates are regarded as fluorides, that is, compounds of fluorine with a 

 metal or combustible, then its equivalent is obtained by adding to that of fluoric acid 

 the weight of one proportion of oxygen supposed to exist in the metallic base ; upon 

 the supposition that the salts are fluates, this will give 10-1-8=18, for the number 

 representing fluorine. 



t Thomson's First Prin. Vol. II, p. 176. 



