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ammonium acetate

n. (context inorganic compound English) The ammonium salt of acetic acid, CH3CO2NH4, that is used as a buffer in standard electrodes

Wikipedia
Ammonium acetate

Ammonium acetate is a chemical compound with the formula NHCHCO. It is a white, hygroscopic solid and can be derived from the reaction of ammonia and acetic acid. It is available commercially.