C7H8 +Cl2----> C7H7Cl +HCl 6
C7H8 +2Cl2---> C7H6Cl2 +2HCl 3
C7H8 +3Cl2---.> C7H5Cl3 +3HCl 1
M,toluen= 92kg/kmol
niu sau n= 690kg/92kg/kmol= 7,5kmol
din totalul de kmoli toluen doar 7,5x6/(6+3+1) se transforma in monoclorotoluen-->4,5kmol monoclorotoluen
m= 4,5kmolx(7x12+7+35,5)kg/kmol-----------------------calculeaza