1)C2H4+2KMnO4+2H2O=CH2-OH-CH2OH+2MnO2+2KOH
CH2OH-CH2OH+Br2r=CH2Br-CH2Br
CH2Br-CH2Br+2KOH=C2H2+2KBr+2H2O
C2H2+H2O=C2H4O
C2H4O+Ag2O=C2H4O2+2Ag
2)C2H4Br2+2KOH=C2H2+2KBr+2H2O
C2H2+HOH=C2H4O
C2H4O+KMnO4+H2SO4=C2H4O2+K2SO4+MnSO4+H2O
CH3-COOH+Cl2=CH2(Cl)-COOH+HCl
CH2(Cl)-COOH+NH3=CH2(NH2)-COOH+HCl