дано
Vppa(C2H5OH) = 62.5 mL
p(C2H5OH) = 0.8 g/cm3
W(C2H5OH) = 92.5%
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m(C2H5OH) = V(ppa C2H5OH) * p(C2H5OH) * W(C2H5OH) / 100%
m(C2H5OH) = 62.5 * 0.8 * 92.5% / 100% = 46.25 g
2C2H5OH+2Na-->C2H5ONa+H2
M(C2H5OH) = 46 g/mol
n(C2H5OH) = m/M = 46.25 / 46 = 1 mol
2n(C2H5OH) = n(H2)
n(H2) = 1 / 2 = 0.5 mol
V(H2) = n(H2) * Vm = 0.5 * 22.4 = 11.2 L
ответ 11.2 л