Alexei78 Дано
W(NaOH) = 10%
p(NaOH) = 1.1 g/ml
m(C6H6) = 23.4 g
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V(ppa NaOH)-?

C6H6+Br2-->C6H5Br+HBr
HBr+NaOH-->NaBr+H2O
M(C6H6) = 78 g/mol
n(C6H6) = m/M = 23.4 / 78 0.3 mol
n(C6H6) = n(NaOH) = 0.3 mol
M(NaOH) = 40 g/mol
m(NaOH) = n*M = 0.3 * 40 = 12 g
m(ppa NaOH) = 12*100% / 10% = 120 g
V(ppa NaOH) =m(ppa NaOH) / p(NaOH) = 120 / 1.1 = 109.09 ml
ответ 109.09 мл