Ethanol

Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is a chemical compound, a simple alcohol with the chemical formula C2H6O. Its formula can be also written as CH3−CH2−OH or C2H5OH (an ethyl group linked to a hydroxyl group), and is often abbreviated as EtOH. Ethanol is a volatile, flammable, colorless liquid with a slight characteristic odor. It is a psychoactive substance and is the principal type of alcohol found in alcoholic drinks. Ethanol is naturally produced by the fermentation of sugars by yeasts or via petrochemical processes, and is most commonly consumed as a popular recreational drug. It also has medical applications as an antiseptic and disinfectant. The compound is widely used as a chemical solvent, either for scientific chemical testing or in synthesis of other organic compounds, and is a vital substance used across many different kinds of manufacturing industries. Ethanol is also used as a clean-burning fuel source. Ethanol is the systematic name defined by the International Union of Pure and Applied Chemistry (IUPAC) for a compound consisting of alkyl group with two carbon atoms (prefix “eth-”), having a single bond between them (infix “-an-”), attached functional group −OH group (suffix “-ol”). The “eth-” prefix and the qualifier “ethyl” in “ethyl alcohol” originally come from the name “ethyl” assigned in 1834 to the group C2H5− by Justus Liebig. He coined the word from the German name Aether of the compound C2H5−O−C2H5 (commonly called “ether” in English, more specifically called “diethyl ether”). According to the Oxford English Dictionary, Ethyl is a contraction of the Ancient Greek αἰθήρ (aithḗr, “upper air”) and the Greek word ὕλη (hýlē, “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. The Oxford English Dictionary claims that it is a medieval loan from Arabic al-kuḥl, a powdered ore of antimony used since antiquity as a cosmetic, and retained that meaning in Middle Latin. The use of “alcohol” for ethanol (in full, “alcohol of wine”) is modern, first recorded 1753, and by the later 18th century referred to “any sublimated substance”; “distilled spirit” used for “the spirit of wine” (shortened from a full expression the spirit of alcohol of wine). The systematic use in chemistry dates to 1850. Ethanol is used in medical wipes and most commonly in antibacterial hand sanitizer gels as an antiseptic for its bactericidal and anti-fungal effects. Ethanol kills organisms by denaturing their proteins and dissolving their lipids and is effective against most bacteria and fungi, and many viruses. However, ethanol is ineffective against bacterial spores. 70% ethanol is the most effective concentration, particularly because of osmotic pressure. Absolute ethanol may inactivate microbes without destroying them because the alcohol is unable to fully permeate the microbe's membrane. Ethanol can also be used as a disinfectant and antiseptic because it causes cell dehydration by disrupting the osmotic balance across cell membrane, so water leaves the cell leading to cell death. Ethanol may be administered as an antidote to methanol and ethylene glycol poisoning.