${CH}_{4}+{I}_{2} \underset{\text { Reversible }}{\stackrel{{hv}}{\longrightarrow}} {CH}_{3}-{I}+{HI}$
$(I)\,\,CH_2 =CH-CH_2Cl$ $(II)\,\,CH_2=CH-CH(CH_3) Cl$
$(III)\,\,CH_2 =C(CH_3)CH_2Cl$ $(IV)\,\, CH_3CH = CH-CH_2Cl$
$(I)$ Benzylchloride
$(II)$ $p-$ Methoxy benzyl chloride
$(III)$ $p-$ Nitro benzyl chloride