Alkene
Leaving Cert Chemistry · Matter in Our World
Higher Level
An unsaturated hydrocarbon containing a carbon to carbon double bond, with the general formula CnH2n when a single double bond is present. The double bond makes alkenes reactive towards addition reactions, which is why they decolourise bromine water.
Ordinary Level
A hydrocarbon with a double bond between two of its carbon atoms. Alkenes turn bromine water from orange to colourless.
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