Specification Point 4.22:
Describe the reactions of alkanes with halogens in the presence of ultraviolet radiation, limited to mono-substitution
Reaction of Alkanes with Halogens
Alkanes: A homologous series of hydrocarbon compounds with only single carbon bonds that has the general formula CnH2n+2
Substitution reaction of alkanes with halogens:
In a substitution reaction, one atom is swapped with another atom. Alkanes undergo a substitution reaction with halogens under the presence of ultraviolet radiation.
Example: Under ultraviolet (UV) radiation, methane reacts with bromine
This reaction is a substitution reaction because one of the hydrogen atoms from the methane is replaced by a bromine atom
Methane + Bromine → Bromomethane + Hydrogen Bromide
CH4 Br2 CH3Br HBr
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