Answer:Free radical mono-halogenation of an alkane is typically conducted using bromine versus chlorine because the bromine radical is less reactive and therefore more selective.
Explanation: Halogenation occurs when a halogen replaces one or more hydrogen atoms in an organic compound ie chlorine or bromine with the reactivity of the halogens decreasing in the order of F2 > Cl2 > Br2 > I2
Since fluorine reacts explosively making it is difficult to control, and iodine is unreactive. Free radical mono-halogenation of an alkane is typically conducted using bromine versus chlorine with Chlorination ie chlorine radical being more reactive and not selective and the Bromination of alkanes ie bromine radical occurring similarly but slower and less reactive but more selective which is due to the fact that a bromine atom is less reactive in the hydrogen abstraction than a chlorine atom evidence in the higher bond energy of H-Cl than H-Br.