Fluate

fluate of lime

fluate of ammonia

fluate of soda

On the other hand, Sir H. Davy contended that fluoric acid, in its strongest form, is anhydrous; for, on combining it with ammoniacal gas, a dry fluate of ammonia is formed, from which no water can be expelled by heat. He maintained, also, that fluoric acid is composed, not of an infammable base and oxygen, but of hydrogen united with a negative electric body, analogous to chlorine, to which he has given the name of fluorine. According to this view, when the metal potassium is brought into contact with fluoric acid, the hydrogen is not derived from water, but from the acid, and the supposed fluate of potash is a compound of fluorine and potassium. The phenomena are explained with the same ease by either theory, although the arguments upon which they depend are thought, by the majority of chemists, to preponderate in favour of the view proposed by Sir [Humphry] Davy. Fluoric acid forms salts by uniting with several bases. Five fluates have hitherto been found native; viz., the fluate of lime, or fluor-spar, the fluo-silicate of alumine, or topaz, the fluate of cerium, the double fluate of cerium and yttria, and the double fluate of soda and alumine, or cryolite. The four latter are very rare minerals, but the first is abundant. Potash unites with fluoric acid in two proportions, forming a fluate and a bifluate, the former of which consists of one atom and the latter of two atoms of acid united with one atom of the alkali. A neutral fluate of soda may be obtained directly from fluoric acid and carbonate of soda. It melts with more difficulty than glass; 100 parts of water, at 212° Fahrenheit, dissolve only 4.3 of it.