Concept, Formula, Properties and Applications

We explain that it is acetic acid and the formula of this substance, besides, its physical, chemical properties and its different uses.

Acetic acid is responsible for the sour smell and taste of vinegar.

What is acetic acid?

Acetic acid, also called methylcarboxylic acid or ethanoic acid, is an organic substance present in the vinegar composition , being responsible for its typical sour smell and taste.

We speak of a weak acid, frequent result of various fermentation processes , such as those that take place in wine (when it is vinegar) or in certain fruits.It is ordinarily used in cooking , as a vegetable cleaner or salad dressing (such as vinegar, that is, diluted with water in 3 to 5% solute).However, in pure proportions it involves different risks to life in general.

In fact, the origin of the vinegar is intimately linked to wine development in ancient times, since the wine boots or barrels that were sour were removed for different use , saying that “the wine had been chopped.” This is due to the activity of the bacteria Mycode rma aceti and requires the presence of oxygen.

Acetic acid formula

Acetic acid responds to the chemical formula C2H4O2.

Acetic acid responds to the chemical formula C2H4O2, being its semi-developed formula CH3COOH.

Seen this way, it is just a molecule of methyl (CH3) with a carboxyl group (-COOH) attached to the carbon atom by single bond.

Physical properties of acetic acid

The appearance of acetic acid is crystalline, at least when it is found as its acetate ion (a salt or ester of the acid).It has a melting point of 16.6 ° C and a boiling point of 117.9 ° C, thanks to which it is possible to separate it from water by distillation .It also has a density of 1049 kg/m3 and a moderate acidity of 4.8.

It is a material flammable and corrosive at the same time , which makes its handling delicate, since it is capable of seriously irritating the skin, the eyes, and the digestive tract (by ingestion) or respiratory (by inhalation).

Chemical properties of acetic acid

Acetic acid belongs to carboxylic acids.

Acetic acid belongs to carboxylic acids (characterized by the presence of a carboxyl functional chemical group:-COOH), and it is usually placed in the classifications between formic or methanoic acid (which has a unique carbon atom) and propanoic acid (which already has a carbon atom chain).

It is a weak acid, common as a biological metabolite and as a substrate for the enzymes acetyltransferases.It is usually obtained by three different methods: methanol carbonylation (CH3OH + CO → CH3COOH), acetaldehyde oxidation (2CH3CHO + O2 → 2CH3COOH), oxidative fermentation (C2H5OH + O2 → CH3COOH + H2O) or anaerobic fermentation (C6H12O6 → 3CH3COOH).

Applications and uses

Acetic acid is used in photographic development.

Acetic acid has numerous applications in the human industry, such as:

• Control of wax moths (galleriosis) in beekeeping.


• Important component (in salts or esters) for the manufacture of nylon, rayon, cellophane and other films.


• Component of fixing substances in the preservation of organic tissues in the laboratory.


• Part of the chemicals used in photographic development.


• Medical dye to reveal Human Papillomavirus (HPV) lesions.


• General purpose cleaner and stain remover component.


• Culinary uses as vinegar.