Дано
m(Na)=23 g
m(H2SO4)=200 g
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V(H2)-?
2Na+H2SO4-->Na2SO4+H2↑
M(Na)=23 g/mol
n(Na)=m/M=23/23 = 1 mol
M(H2SO4)=98 g/mol
n(H2SO4) = m/M=200/98 = 2.04 mol
n(Na)2n(NA)=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