Ammonium acetate, also known as spirit of Mindererus in
aqueous
An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, also known as sodium chloride (NaCl), in wat ...
solution, is a chemical compound with the formula NH
4CH
3CO
2. It is a white,
hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption (chemistry), absorption or adsorption from the surrounding Natural environment, environment, which is usually at normal or room temperature. If water mol ...
solid and can be derived from the reaction of
ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...
and
acetic acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main compone ...
. It is available commercially.
History
The synonym Spirit of Mindererus is named after R. Minderer, a physician from
Augsburg
Augsburg ( , ; ; ) is a city in the Bavaria, Bavarian part of Swabia, Germany, around west of the Bavarian capital Munich. It is a College town, university town and the regional seat of the Swabia (administrative region), Swabia with a well ...
.
Uses
It is the main precursor to
acetamide:
:NH
4CH
3CO
2 → CH
3C(O)NH
2 + H
2O
It is also used as a diuretic.
[
]
Buffer
As the salt of a weak acid and a weak base, ammonium
Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged (cationic) polyatomic ion, molecular ion with the chemical formula or . It is formed by the protonation, addition of a proton (a hydrogen nucleu ...
acetate
An acetate is a salt formed by the combination of acetic acid with a base (e.g. alkaline, earthy, metallic, nonmetallic, or radical base). "Acetate" also describes the conjugate base or ion (specifically, the negatively charged ion called ...
is often used with acetic acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main compone ...
to create a buffer solution
A buffer solution is a solution where the pH does not change significantly on dilution or if an acid or base is added at constant temperature. Its pH changes very little when a small amount of strong acid or base is added to it. 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. 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.
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
Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the gen ...
.
*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
Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives, such as vinegar ( pickling), salt ( salting), smoke ( smoking) and sugar ( crystallization), have been used f ...
as an acidity regulator; INS number 264. It is approved for usage in Australia and New Zealand.
Production
Ammonium acetate is produced by the neutralization of acetic acid with ammonium carbonate or by saturating glacial acetic acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main compone ...
with ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...
.
References
External links
{{Ammonium salts
Ammonium compounds
Acetates