fluoric acid

Noun

fluoric acid (uncountable)

1. (archaic, uncommon) An oxyacid of fluorine, HFO₃, said to be known only in laboratory environments and not to exist in nature.
   • […] that this is not hypofluorous acid but fluoric acid, HFO₃. Thus the behaviour of these fluorides supports the view that the reaction of halides with water takes place through an intermediate co-ordination compound; […]1933, Chemical Society, Annual Reports on the Progress of Chemistry, volume 30, Chemical Society, page 116
   • Since fluorine must always be negative relative to oxygen, oxyacids analogous to those of the other halogens cannot be expected (24). Almost certainly, perfluoric acid HFO₄, or fluoric acid HFO₃, or hypofluorous acid HOF, will not therefore be prepared.1959, American Rocket Society, “Jet Propulsion”, in ARS Journal, volume 29, American Rocket Society, page 96
2. (archaic, proscribed) Hydrofluoric acid.
   • Pure fluoric acid causes a flocculent precipitate in barytic water, which an excess of the same acid or of the nitric or muriatic acids, will redissolve. […] Fluoric acid diluted with six or seven parts of water dissolves zinc rapidly, and with disengagement of much hydrogen. The solution at first...1807, Arthur Aikin, Charles Rochemont Aikin, “Alkaline and Earthy Fluats”, in A Dictionary of Chemistry and Mineralogy , with an Account of the Processes Employed in Many of the Most Important...
   • 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...1837, “Fluoric acid”, in The Popular Encyclopedia: Being a General Dictionary of Arts, Sciences, Literature, Biography, History, and Political Economy. Reprinted from the American Edition of the...