C6H6 +CH3CL----.>C6H5-CH3+HCl ori a moli
C6H6 +2CH3Cl---> C6H4(CH3)2 + 2HCl ori b moli
C6H6..................................>C6H6 ori c moli
M,C6H6=78g/mol
M,C7H8=92g/mol
M,C8H10=106g/mol
78a+92b+106c=86,4g
a/b=1/2 b=2a
a/c=1/3 c=3a
inlocuin b si c in prima ecuatie---> a= 0,16mol, b=0,32mol, c=0,48mol
masa de bebzen,m= (a+b+c)x78g= 6ax78g= calculeaza !!!!