(colorless) (purple) (colorless) (brown ppt.) Reaction of an alkene with aqueous potassium permanganate results in addition of two hydroxyl groups to each side of the double bond to form a glycol. To ...

Complete combustion of alkenes produces carbon dioxide and water, provided there is a plentiful supply of oxygen. Incomplete combustion of alkenes occurs where oxygen is limited and produces 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. The slideshow shows this process.