Ethanol

Names Pronunciation Preferred IUPAC nameOther names Identifiers Abbreviations EtOH 1718733 ChEBIChEMBLChemSpiderDrugBankECHA InfoCard100.000.526787 KEGGUNIIUN numberUN 1170 Properties C₂H₆OMolar mass46.069 g·mol Appearance Colorless liquid Odorwine-like, pungent Density0.78945 g/cm (at 20 °C) Melting point−114.14 ± 0.03 °C (−173.45 ± 0.05 °F; 159.01 ± 0.03 K) Boiling point78.23 ± 0.09 °C (172.81 ± 0.16 °F; 351.38 ± 0.09 K) Misciblelog P−0.31 Vapor pressure5.95 kPa (at 20 °C) Acidity (pK_a) 15.9 (H₂O), 29.8 (DMSO) −33.60·10 cm/mol 1.3611 Viscosity1.2 mPa·s (at 20 °C), 1.074 mPa·s (at 25 °C) 1.69 D Hazards GHS labelling: DangerH225, H319, H360DP210, P233, P240, P241, P242, P305+P351+P338NFPA 704 (fire diamond) Flash point14 °C (57 °F; 287 K) (Absolute) Lethal dose or concentration (LD, LC): NIOSH (US health exposure limits): TWA 1000 ppm (1900mg/m) TWA 1000 ppm (1900mg/m) 3300 ppm Safety data sheet (SDS) Related compounds Supplementary data page Ethanol (data page)

Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formulaCH₃CH₂OH. It is an alcohol, with its formula also written as C₂H₅OH, C₂H₆O, or EtOH, where Et is the pseudoelement symbol for ethyl. Ethanol is a volatile, flammable, colorless liquid with a pungent taste. As a central nervous system (CNS) depressant, it is the active ingredient in alcoholic beverages, and the second most consumed drug globally behind caffeine.

Ethanol is naturally produced by the fermentation process of sugars by yeasts or via petrochemical processes such as ethylene hydration. Historically it was used as a general anesthetic, and has modern medical applications as an antiseptic, disinfectant, solvent for some medications, and antidote for methanol poisoning and ethylene glycol poisoning. It is used as a chemical solvent and in the synthesis of organic compounds, and as a fuel source for lamps, stoves, and internal combustion engines. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2023, world production of ethanol fuel was 112.0 gigalitres (2.96×10 US gallons), coming mostly from the U.S. (51%) and Brazil (26%).

The term "ethanol", originates from the ethyl group coined in 1834 and was officially adopted in 1892, while "alcohol"—now referring broadly to similar compounds—originally described a powdered cosmetic and only later came to mean ethanol specifically. Ethanol occurs naturally as a byproduct of yeast metabolism in environments like overripe fruit and palm blossoms, during plant germination under anaerobic conditions, in interstellar space, in human breath, and in rare cases, is produced internally due to auto-brewery syndrome.

Ethanol has been used since ancient times as an intoxicant. Production through fermentation and distillation evolved over centuries across various cultures. Chemical identification and synthetic production began by the 19th century.