or

CHCl3+LiAlH4------> CH4 (under extreme condition of temperature and pressure)

CH4+Cl2--------->CH3Cl+HCl (Chlorination in presence of sunlight)

CH3Cl+Na--------->C2H6 (Wurtz reaction)

C2H6+Br2---------->CH3-CH2-Br (Bromination in presence of UV rays)