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/ˈæl.kin/
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/ˈæl.kin/
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/ˈæl.kin/
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/ˈæl.kin/
Plural
alkenes
An alkene is a type of hydrocarbon that contains at least one carbon–carbon double bond, making it chemically reactive and essential in plastics, fuels, and synthesis — think of ethene, the simplest alkene, which ripens fruit and builds polyethylene bags.
Ethene is the most widely produced organic compound and serves as a fundamental alkene in industrial chemistry.
Alkenes undergo addition reactions readily, such as when bromine water decolorizes upon mixing with cyclohexene.
In organic synthesis, chemists often convert alcohols to alkenes using acid-catalyzed dehydration.
The presence of a C=C double bond defines an alkene and distinguishes it from the fully saturated alkane.
Catalytic cracking of petroleum yields smaller alkenes like propene, crucial for making synthetic rubber and plastics.
alk-
Comes from the Arabic word 'al-qily' (القلي), meaning 'ashes of saltwort', later adopted into Latin as 'alkali'. In organic chemistry nomenclature, 'alk-' is a combining form derived from 'alkane', itself built on 'alkali' via historical association with hydrocarbons isolated from alkaline sources. It denotes saturated/unsaturated hydrocarbon series: 'alkane' (saturated), 'alkene' (one double bond), 'alkyne' (one triple bond). Examples include alkane, alkene, alkyne, alcohol (historically linked via 'al-' prefix and fermentation chemistry), aldehyde.
-ene
Comes from the Greek suffix '-ēnē' (ηνη), used in chemical nomenclature since the 19th century to denote unsaturation—specifically the presence of a carbon–carbon double bond. It was modeled after 'ethylene' (from 'ethyl' + '-ene') and generalized by IUPAC. The suffix carries the core meaning 'characterized by a double bond'. Examples include ethene, propene, butene, benzene (historically, though aromatic), toluene (non-systematic but etymologically related).