Aluminium acetate or aluminium ethanoate
(also "aluminum ~"), sometimes abbreviated AlAc in
geochemistry
Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the Earth's crust and its oceans. The realm of geochemistry extends beyond the Earth, encompassing ...
, can refer to a number of different salts of aluminum 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 compon ...
. In the solid state, three salts exist under this name: basic
aluminium monoacetate, (HO)
2AlCH
3CO
2, basic
aluminium diacetate, HOAl(CH
3CO
2)
2,
and neutral
aluminium triacetate, Al(CH
3CO
2)
3. In aqueous solution, aluminium triacetate hydrolyses to form a mixture of the other two,
and all solutions of all three can be referred to as "aluminium acetate" as the species formed co-exist and inter-convert in
chemical equilibrium
In a chemical reaction, chemical equilibrium is the state in which both the reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of th ...
.
Aluminium monoacetate
Aluminium monoacetate, also known as dibasic aluminium acetate, forms from Al(OH)
3 and dilute aqueous acetic acid. More concentrated acid leads to the di- and triacetate.
Aluminium diacetate
Aluminium diacetate, also known as basic aluminium acetate, is prepared from aqueous aluminium acetate solution resulting in a white powder.
This
basic salt forms from the hydrolysis of the triacetate in water.
Aluminium triacetate
Aluminium triacetate is a
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
that is prepared by heating
aluminium chloride
Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula . It forms hexahydrate with the formula , containing six water molecules of hydration. Both are colourless crystals, but samples are often contam ...
(AlCl
3) or Al powder with a mixture of
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 compon ...
(CH
3COOH) and
acetic anhydride
Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH3CO)2O. Commonly abbreviated Ac2O, it is the simplest isolable anhydride of a carboxylic acid and is widely used as a reagent in organic synthesis. It is a ...
(C
4H
6O
3).
It is referred as the normal salt and is only made in the absence of water at a relatively high temperature like 180 °C.
References
{{Chemistry index
Aluminium compounds
Acetates