Verified answer

2CH4 (1500*C)--> C2H2 + 3H2

C2H2 + 2H2 (Ni, t*)--> C2H6

C2H6 + Cl2 (свет)--> C2H5Cl + HCl

C2H5Cl + KOH(водный) --> C2H5OH + KCl

C2H5OH + CuO (t*)--> CH3CHO + Cu + H2O

CH3CHO + 2Cu(OH)2 (t*)--> CH3COOH + Cu2O + 2H2O