Нужно решить цепочку: C2H5Cl-->C2H5OH-->CH3CHO-->CH3COOH-->CH2ClCOOH
C2H5Cl+KOH =C2H5OH+KCl C2H5OH+CuO=Cu+H2O+CH3COH CH3COH + Ag2O=2Ag+CH3COOH CH3COOH + Cl2=CH2ClCOOH+HCl