Дано
m(C6H6) = 156 g
V(Br) = 110 mL
p(Br2) = 3.1 g/mL
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m(C6H5Br)-?
m(Br) = V*p = 110*3.1 = 341 g
M(C6H6) = 78 g/mol
n(C6H6) = m/M = 156/78 = 2 mol
M(Br2) = 80*2 = 160 g/mol
n(Br2) = m/M = 341/160 = 2.13 mol
n(C6H6)< n(Br2)
M(C6H5Br) = 157 g/mol
C6H6+Br2-->C6H5Br+HBr
n(C6H6) = n(C6H5Br) = 2 mol
m(C6H5Br) = n*M = 2*157 = 314 g
ответ 314 г