Ethanol /ˈɛθənɒl/, also commonly called ethyl alcohol, drinking alcohol, or simply alcohol is the principal type of alcohol found inalcoholic beverages, produced by the fermentation of sugars by yeasts. It is a neurotoxic psychoactive drug and one of the oldest recreational drugs used by humans. It can cause alcohol intoxication when consumed in sufficient quantity.
Ethanol is a volatile, flammable, colorless liquid with a slight chemical odor. It is used as an antiseptic, a solvent, a fuel, and, due to its low freezing point, the active fluid in post-mercury thermometers. Its structural formula, CH3CH2OH, is often abbreviated as C2H5OH, C2H6O or EtOH.
Ethanol is the systematic name defined by the International Union of Pure and Applied Chemistry (IUPAC) for a molecule with two carbon atoms (prefix “eth-“), having a single bond between them (suffix “-ane”), and an attached functional group-OH group (suffix “-ol”).
The prefix ethyl was coined in 1834 by the German chemist Justus Liebig. Ethyl is a contraction of the French word ether (any substance that evaporated or sublimated readily at room temperature) and the Greek word ύλη (hyle, substance).
The name ethanol was coined as a result of a resolution that was adopted at the International Conference on Chemical Nomenclature that was held in April 1892 in Geneva, Switzerland.
The term “alcohol” now refers to a wider class of substances in chemistry nomenclature, but in common parlance it remains the name of ethanol. Ultimately a medieval loan from Arabic al-kuḥl, use of alcohol in this sense is modern, introduced in the mid 18th century. Before that time, Middle Latin alcohol referred to “powdered ore of antimony; powdered cosmetic”, by the later 17th century “any sublimated substance; distilled spirit” use for “the spirit of wine” (shortened from a full expression alcohol of wine) recorded 1753. The systematic use in chemistry dates to 1850.
Ethanol is a 2-carbon alcohol. Its molecular formula is CH3CH2OH. An alternative notation is CH3–CH2–OH, which indicates that the carbon of a methyl group (CH3–) is attached to the carbon of a methylene group (–CH2–), which is attached to the oxygen of ahydroxyl group (–OH). It is a constitutional isomer of dimethyl ether. Ethanol is sometimes abbreviated as EtOH, using the common organic chemistry notation of representing the ethyl group (C2H5-) with Et.