n=mp/mt*100==>mt=mp*100/n=6750/80=84.375 kg C6H5-Cl
78kg....................112.5kg
C6H6 + Cl2 ---> C6H5-Cl + HCl
x=58.5kg.............84.375kg
puritatea=mpur/mimpur*100==>mimpur=mpur*100/puritate=58.5*100/75=78 Kg C6H6 impur
MC6H6=78kg/kmol
MC6H5-Cl=112.5kg/kmol