(Also called olefins.) Monoalkenes are hydrocarbon species with general formula CnH2n, where n is an integer, containing one unsaturated carbon–carbon bond. Alkenes are emitted in large quantities by [..]

unsaturated hydrocarbons consisting only of carbon and hydrogen and containing one or more double bonds. General formula is

Hydrocarbons that have a double bond between two carbon atoms; general molecular formula, CnH2n.

[noun] A group of hydrocarbons with the general formula CnH(2n). Alkenes contain at least one carbon-carbon double bond; common examples include ethylene. Appears in modules:

Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)

Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)

Unsaturated hydrocarbons of the type cn-h2n, indicated by the suffix -ene. (12 Dec 1998)

the homologous series of aliphatic hydrocarbons containing one double (unsaturated) carbon-to-carbon bond, consisting of ethene (C2H4), propene (C3H6), butene (C4H8),etc., also known as olefins.

The group of unsaturated hydrocarbons having the general formula CnH2n and characterized by being highly chemically reactive. Also referred to as olefins.

alkene|lang=en