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Ammonium hydrogen fluoride is the inorganic compound with the formula NH4HF2 or NH4F·HF. It is produced from ammonia and hydrogen fluoride. This colourless salt is a glass-etchant and an intermediate in a once-contemplated route to hydrofluoric acid.
A 2035 (OTTO) Ammonium bifluoride, 98% Cas 1341-49-7 - used in ceramics, electroplating, component of glass etchants as well as food processing equipment disinfectant.