Дано
V(H2) = 1 L
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V(O2)-?
m(H2O)-?
2H2O-->2H2+O2
n(H2) = V(H2) / Vm = 1/22.4 = 0.045 mol
2n(H2) = 2n(H2O) = 0.045 mol
M(H2O) = 18 g/mol
m(H2O) = n*M = 0.045 * 18 = 0.81 g
2n(H2) = n(O2)
n(O2) = 0.045 / 2 = 0.0225 mol
V(O2) = n*Vm = 0.0225 * 22.4 = 0.504 L
ответ 0.81 г, 0.504 L