=> 8 moli se transforma
1mol.................112,5g
C6H6 + Cl2 -> C6H5-Cl + HCl
8moli................x=900g
1mol........78g
C6H6 -> C6H6
2moli.....y=156g
masa amestecului de reactie: 900+156=1056g
1056g...................100%
35,5g.........................z%
z=35,5*100/1056=3,36% Cl