CH2==CH2+CL2=CH2CL-CH2CL
CH2CL-CH2CL+2NaOH= CH2OH-CH2OH+2Nacl
CH2OH-CH2OH=CH-CH+2H2O;
CH-CH+CL2= CHCL=CHCL;
nCHCL=CHCL =-(CHCL-CHCL)n-