Question

CH4 → CH3-CH3→ CH3-CH2-OH→CH3-CH3

Answer 1

CH4+Cl2=CH3Cl+HCl

CH3Cl+2Na+CH3Cl=CH3-CH3+2NaCl

С2Н6+Cl2-> C2H5Cl+HCl 
C2H5Cl+NaOH->C2H5OH+NaCl 

C2H5OH (H+. Hg. t>140)=C2H4+H2O

C2H4+H2=CH3-CH3