Alcohol

This article is about the generic chemistry term. For the kind of alcohol found in alcoholic beverages, see Ethanol. For beverages containing alcohol, see Alcoholic beverage. For other uses, seeAlcohol (disambiguation).

The hydroxyl (OH) functional group in an alcohol molecule

Ball-and-stick model of the hydroxyl (OH) functional group in an alcohol molecule

In chemistry, an alcohol is any organic compound in which a hydroxyl functional group (-OH) is bound to a carbon atom, usually connected to other carbon or hydrogen atoms.

An important class are the simple acyclic alcohols, the general formula for which is C_nH_2n+1OH. Of those, ethanol (C₂H₅OH) is the type of alcohol found in alcoholic beverages, and in common speech the word alcohol refers specifically to ethanol.

Other alcohols are usually described with a clarifying adjective, as in isopropyl alcohol (propan-2-ol) or wood alcohol (methyl alcohol, or methanol). The suffix -olappears in the IUPAC chemical name of all substances where the hydroxyl group is the functional group with the highest priority; in substances where a higher priority group is present the prefix hydroxy- will appear in the IUPAC name. The suffix -ol in non-systematic names (such as paracetamol or cholesterol) also typically indicates that the substance includes a hydroxyl functional group and, so, can be termed an alcohol. But many substances (such as citric acid, lactic acid, andsucrose) contain one or more hydroxyl functional groups without using the suffix.