Ammonium Fluoride

Ammonium fluoride, [NH4]F, may be obtained by neutralizing ammonia with hydrofluoric acid. It crystallizes as small prisms, having a sharp saline taste, and is exceedingly soluble in water. It decomposes silicates, and thus glass, on being heated with them, a property shared among all soluble fluorides. For this reason it cannot be handled in glass test tubes or apparatus during laboratory work. It also has sublimes when heated - a property common among ammonium salts. This is due to the fact that the salt decomposes to ammonia and hydrogen fluoride when heated, and the two gases react to form ammonium fluoride when cold, i.e. the reaction is reversible: [NH4]F ↔ NH3 + HF
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chemical Formula NH3F, ammonium fluoride is a toxic, corrosive chemical used to buffer hydrofluoric acid, HF, in buffered oxide etch, BOE. Fluorine is not only toxic but may be absorbed through the skin without immediate evidence of irritation and later react with the calcium in bones and or poison the person exposed to the chemical. Ammonium fluoride is commonly sold as a 40% solution with a density of 1.11Kg/L.