Does Alkene Decolourise Bromine Water?

Bromine water is an orange solution of bromine. It becomes colourless when it is shaken with an alkene. Alkenes can decolourise bromine water, but alkanes cannot. ... This has the effect of 'saturating' the molecule, and will turn an alkene into an alkane.

Why do alkenes turn bromine water Colourless?

An alkene will turn brown bromine water colourless as the bromine reacts with the carbon-carbon double bond. In fact this reaction will occur for unsaturated compounds containing carbon-carbon double bonds. An alkane undergoes no reaction with bromine water and therefore there is no colour change.

What alkene does not Decolourise bromine water?

Alkanes are saturated hydrocarbons, which does not decolourise the bromine water.