Reactions Of Alkanes With Bromine

Question 1

What has to be present for alkanes to react with bromine?

Answer 1

UV light (sunlight)

Question 2

What happens during a substitution reaction with bromine?

Answer 2

A bromine atom takes the place of a hydrogen atom in the alkane to form a bromoalkane (and hydrogen bromide)
It is therefore a substitution reaction
If the alkane is left with bromine in sunlight the brown colour of the bromine will disappear

Question 3

Equation for bromine reaction

Answer 3

Methane + bromine (brown) —> bromomethane (colourless) + hydrogen bromide

CH4 + Br2 —> CH3BR + HBr