Cl-CH2-CH2-Cl + 2KOH(спирт) = 2KCl + 2H2O + СH≡CH
СH≡CH + 2H2 = CH3-CH3
CH3-CH3 + Cl2 = HCl + CH3-CH2CL
CH3-CH2CL + KOH(водный) = KCl + CH3-CH2-OH
CH3-CH2-OH = CH2=CH2 + H2O
CH2=CH2 + Cl2 = CH2Cl-CH2Cl
CH2Cl-CH2Cl + 2KOH(водный) = HO-CH2-CH2-OH + 2KCl