106no.
In the beginning, the Cl2 will react with CH4 to give CH3Cl only. But when concentration of chloromethane increases, then there is competition between the methane and chloromethane to react with chlorine. When [chloromethane]>[methane] then chlorine reacts with chloromethane to give dichloromethane.
Similarly when [dichloromehtane]>[chloromethane] then chlorine will react with dichloromethane to form trichloromethane and similarly CCl4 will also form
