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When bromine is added to an alkane, why does the solution become colourless? When bromine is added to an alkene, why does the solution remain brown?

1 Answer
Feb 19, 2018


The change in structure from a diatomic #Br_2# to an ionic or polar covalent #Br-C-R# bond changes the light adsorption/reflection wavelength.


You have the reactions reversed. Bromine reacts with ALKENES, not Alkanes.

This effect is also seen with other halogens, most notably Iodine.