Answer:
See Explanation and image attached
Step-by-step explanation:
Methane is an alkane. The most common reaction for which alkanes are known is substitution reaction. In a substitution reaction involving alkanes, , one or more atoms of hydrogen is/are replaced.
In the presence of sunlight and molecular chlorine gas, homolytic fission of Cl2 takes place leading to the production of chlorine radicals.
These radicals react with methane in several propagation steps as shown until the tetrachlorination product is finally obtained.