ethanol ethanol ethanol (abbr. etoh; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. it is an alcohol with the chemical formula c2h6o. its formula can also be written as ch3−ch2−oh or c2h5oh (an ethyl group linked to a hydroxyl group). ethanol is a volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. it is a psychoactive recreational drug, and the active ingredient in alcoholic drinks. for ethanol as a drug or medicine, see alcohol (drug) and alcohols (medicine). ethanol full structural formula of ethanol skeletal formula of ethanol ball-and-stick model of ethanol space-filling model of ethanol names pronunciation /ˈɛθənɒl/ preferred iupac name ethanol other names absolute alcoholalcoholcologne spiritdrinking alcoholethylic alcoholetohethyl alcoholethyl hydroxideethylene hydrateethylolgrain alcoholhydroxyethanemethylcarbinol identifiers cas number 64-17-5 y 3d model (jsmol) interactive image 3dmet b01253 beilstein reference 1718733 chebi chebi:16236 y chembl chembl545 y chemspider 682 y drugbank db00898 y echa infocard 100.000.526 gmelin reference 787 iuphar/bps 2299 kegg c00469 pubchem cid 702 unii 3k9958v90m y un number un 1170 comptox dashboard (epa) dtxsid9020584 inchi inchi=1s/c2h6o/c1-2-3/h3h,2h2,1h3 ykey: lfqscwfljhtthz-uhfffaoysa-n yinchi=1/c2h6o/c1-2-3/h3h,2h2,1h3key: lfqscwfljhtthz-uhfffaoyab smiles occ properties chemical formula c2h6o molar mass 46.069 g·mol−1 appearance colourless liquid odor wine-like, pungent density 0.78945 g/cm3 (at 20 °c) melting point −114.14 ± 0.03 °c (−173.45 ± 0.05 °f; 159.01 ± 0.03 k) boiling point 78.23 ± 0.09 °c (172.81 ± 0.16 °f; 351.38 ± 0.09 k) solubility in water miscible log p −0.18 vapor pressure 5.95 kpa (at 20 °c) acidity (pka) 15.9 (h2o), 29.8 (dmso) magnetic susceptibility (χ) −33.60·10−6 cm3/mol refractive index (nd) 1.3611 viscosity 1.2 mpa·s (at 20 °c), 1.074 mpa·s (at 25 °c) dipole moment 1.69 d hazards ghs labelling: pictograms signal word danger hazard statements h225, h319 precautionary statements p210, p233, p240, p241, p242, p305+p351+p338 nfpa 704 (fire diamond) 2 3 0 flash point 14 °c (absolute) lethal dose or concentration (ld, lc): ld50 (median dose) 7340 mg/kg (oral, rat) 7300 mg/kg (mouse) niosh (us health exposure limits): pel (permissible) twa 1000 ppm (1900 mg/m3) rel (recommended) twa 1000 ppm (1900 mg/m3) idlh (immediate danger) n.d. safety data sheet (sds) related compounds related compounds ethane methanol supplementary data page ethanol (data page) except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). n verify (what is yn ?) infobox references 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. ethanol also can be dehydrated to make ethylene, an important chemical feedstock. as of 2006, world production of ethanol was 51 gigalitres (1.3×1010 us gallons), coming mostly from brazil and the u.s. etymology ethanol is the systematic name defined by the international union of pure and applied chemistry for a compound consisting of an alkyl group with two carbon atoms (prefix "eth-"), having a single bond between them (infix "-an-") and an attached −oh functional 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 on naming alcohols and phenols 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. 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 and was first recorded in 1753. before the late 18th century the term "alcohol" generally referred to any sublimated substance. uses medical main article: alcohol (medicine) anesthetic ethanol is the oldest known sedative, used as an oral general anesthetic during surgery in ancient mesopotamia and in medieval times. mild intoxication starts at a blood alcohol concentration of 0.03-0.05% and induces anesthetic coma at 0.4%. however, this use carried the high risk of deadly alcohol intoxication and pulmonary aspiration on vomit, which led to use of alternatives in antiquity, such as opium and cannabis, and later diethyl ether starting in the 1840s. antiseptic 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 microorganisms by dissolving their membrane lipid bilayer and denaturing their proteins, and is effective against most bacteria, fungi and viruses. however, it is ineffective against bacterial spores, but that can be alleviated by using hydrogen peroxide. a solution of 70% ethanol is more effective than pure ethanol because ethanol relies on water molecules for optimal antimicrobial activity. 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 the cell membrane, so water leaves the cell leading to cell death. antidote ethanol may be administered as an antidote to ethylene glycol poisoning and methanol poisoning. ethanol serves this process by acting as a competitive inhibitor against methanol and ethylene glycol for alcohol dehydrogenase. though it has more side effects, ethanol is less expensive and more readily available than fomepizole, which is also used as an antidote for methanol and ethylene glycol poisoning. medicinal solvent ethanol, often in high concentrations, is used to dissolve many water-insoluble medications and related compounds. liquid preparations of pain medications, cough and cold medicines, and mouth washes, for example, may contain up to 25% ethanol and may need to be avoided in individuals with adverse reactions to ethanol such as alcohol-induced respiratory reactions. ethanol is present mainly as an antimicrobial preservative in over 700 liquid preparations of medicine including acetaminophen, iron supplements, ranitidine, furosemide, mannitol, phenobarbital, trimethoprim/sulfamethoxazole and over-the-counter cough medicine. pharmacology in mammals, ethanol is primarily metabolized in the liver and stomach by alcohol dehydrogenase (adh) enzymes. these enzymes catalyze the oxidation of ethanol into acetaldehyde (ethanal): ch3ch2oh + nad+ → ch3cho + nadh + h+ when present in significant concentrations, this metabolism of ethanol is additionally aided by the cytochrome p450 enzyme cyp2e1 in humans, while trace amounts are also metabolized by catalase. the resulting intermediate, acetaldehyde, is a known carcinogen, and poses significantly greater toxicity in humans than ethanol itself. many of the symptoms typically associated with alcohol intoxication—as well as many of the health hazards typically associated with the long-term consumption of ethanol—can be attributed to acetaldehyde toxicity in humans. the subsequent oxidation of acetaldehyde into acetate is performed by aldehyde dehydrogenase (aldh) enzymes. a mutation in the aldh2 gene that encodes for an inactive or dysfunctional form of this enzyme affects roughly 50% of east asian populations, contributing to the characteristic alcohol flush reaction that can cause temporary reddening of the skin as well as a number of related, and often unpleasant, symptoms of acetaldehyde toxicity. this mutation is typically accompanied by another mutation in the alcohol dehydrogenase enzyme adh1b in roughly 80% of east asians, which improves the catalytic efficiency of converting ethanol into acetaldehyde. recreational main articles: alcohol (drug) and alcoholic drink as a central nervous system depressant, ethanol is one of the most commonly consumed psychoactive drugs. despite alcohol's psychoactive, addictive, and carcinogenic properties, it is readily available and legal for sale in most countries. there are laws regulating the sale, exportation/importation, taxation, manufacturing, consumption, and possession of alcoholic beverages. the most common regulation is prohibition for minors. fuel corn vs ethanol production in the united states total corn production (bushels) (left) corn used for ethanol fuel (bushels) (left) percent of corn used for ethanol (right) engine fuel energy content (lower heating value) of some fuels compared with ethanol. fuel typemj/lmj/kgresearchoctanenumber dry wood (20% moisture)~19.5 methanol17.919.9108.7 ethanol21.226.8 108.6 e85(85% ethanol, 15% gasoline)25.233.2105 liquefied natural gas25.3~55 autogas (lpg)(60% propane + 40% butane)26.850 aviation gasoline(high-octane gasoline, not jet fuel)33.546.8100/130 (lean/rich) gasohol(90% gasoline + 10% ethanol)33.747.193/94 regular gasoline/petrol34.844.4min. 91 premium gasoline/petrolmax. 104 diesel38.645.425 charcoal, extruded5023 the largest single use of ethanol is as an engine fuel and fuel additive. brazil in particular relies heavily upon the use of ethanol as an engine fuel, due in part to its role as one of the world's leading producers of ethanol. gasoline sold in brazil contains at least 25% anhydrous ethanol. hydrous ethanol (about 95% ethanol and 5% water) can be used as fuel in more than 90% of new gasoline-fueled cars sold in the country. the us and many other countries primarily use e10 (10% ethanol, sometimes known as gasohol) and e85 (85% ethanol) ethanol/gasoline mixtures. over time, it is believed that a material portion of the ≈150-billion-us-gallon (570,000,000 m3) per year market for gasoline will begin to be replaced with fuel ethanol. usp grade ethanol for laboratory use australian law limits the use of pure ethanol from sugarcane waste to 10% in automobiles. older cars (and vintage cars designed to use a slower burning fuel) should have the engine valves upgraded or replaced. according to an industry advocacy group, ethanol as a fuel reduces harmful tailpipe emissions of carbon monoxide, particulate matter, oxides of nitrogen, and other ozone-forming pollutants. argonne national laboratory analyzed greenhouse gas emissions of many different engine and fuel combinations, and found that biodiesel/petrodiesel blend (b20) showed a reduction of 8%, conventional e85 ethanol blend a reduction of 17% and cellulosic ethanol 64%, compared with pure gasoline. ethanol has a much greater research octane number (ron) than gasoline, meaning it is less prone to pre-ignition, allowing for better ignition advance which means more torque, and efficiency in addition to the lower carbon emissions. ethanol combustion in an internal combustion engine yields many of the products of incomplete combustion produced by gasoline and significantly larger amounts of formaldehyde and related species such as acetaldehyde. this leads to a significantly larger photochemical reactivity and more ground level ozone. this data has been assembled into the clean fuels report comparison of fuel emissions and show that ethanol exhaust generates 2.14 times as much ozone as gasoline exhaust. when this is added into the custom localized pollution index of the clean fuels report, the local pollution of ethanol (pollution that contributes to smog) is rated 1.7, where gasoline is 1.0 and higher numbers signify greater pollution. the california air resources board formalized this issue in 2008 by recognizing control standards for formaldehydes as an emissions control group, much like the conventional nox and reactive organic gases (rogs). more than 20% of brazilian cars are able to use 100% ethanol as fuel, which includes ethanol-only engines and flex-fuel engines. flex-fuel engines in brazil are able to work with all ethanol, all gasoline or any mixture of both. in the united states, flex-fuel vehicles can run on 0% to 85% ethanol (15% gasoline) since higher ethanol blends are not yet allowed or efficient. brazil supports this fleet of ethanol-burning automobiles with large national infrastructure that produces ethanol from domestically grown sugarcane. ethanol's high miscibility with water makes it unsuitable for shipping through modern pipelines like liquid hydrocarbons. mechanics have seen increased cases of damage to small engines (in particular, the carburetor) and attribute the damage to the increased water retention by ethanol in fuel. ethanol pump station in são paulo, brazila ford taurus fueled by ethanol in new york cityu.s. postal service truck running on e85 in minnesota rocket fuel ethanol was commonly used as fuel in early bipropellant rocket (liquid-propelled) vehicles, in conjunction with an oxidizer such as liquid oxygen. the german a-4 ballistic rocket of world war ii (better known by its propaganda name v-2), which is credited