Buffer

As the salt of a weak acid and a weak base, ammonium acetate is often used with acetic acid to create a buffer solution. Ammonium acetate is volatile at low pressures. Because of this, it has been used to replace cell buffers that contain non-volatile salts in preparing samples for mass spectrometry.^[8] It is also popular as a buffer for mobile phases for HPLC with ELSD and CAD-based detection for this reason. Other volatile salts that have been used for this include ammonium formate.

When dissolving ammonium acetate in pure water, the resulting solution typically has a pH of 7, because the equal amounts of acetate and ammonium neutralize each other. However, ammonium acetate is a dual component buffer system, which buffers around pH 4.75 ± 1 (acetate) and pH 9.25 ± 1 (ammonium), but it has no significant buffer capacity at pH 7, contrary to common misconception.^[9]

Other

• a biodegradable de-icing agent.
• a catalyst in the Knoevenagel condensation and as a source of ammonia in the Borch reaction in organic synthesis.
• a protein precipitating reagent in dialysis to remove contaminants via diffusion.
• a reagent in agricultural chemistry for determination of soil CEC (cation exchange capacity) and determination of available potassium in soil wherein the ammonium ion acts as a replacement cation for potassium.
• part of Calley's method for lead artifact conservation

Food additive

Ammonium acetate is also used as a food additive as an acidity regulator; INS number 264. It is approved for usage in Australia and New Zealand.^[10]