Freeradical Substitution

Initation

Cl-Cl = Cl. + Cl.

Propagation

CH4 + Cl. = CH3 + HCl

CH3 + Cl2 =CH3 + Cl.

Termination

Cl. + Cl. = Cl2

CH3 + Cl = CH3Cl

CH3. + CH3. = C2H6

3 Pieces of Evidence that Confirms this Mechanism

Formation of C2H6 if methane is used

If UV is stopped, reaction slows

Adding radical promoters (eg.Tetraethyl lead) speeds rate of reaction

Substances created uf ethane is used:

Ethyl radcials, chloroethane, butane