Fe3O4+4H2-to>3Fe+4H2O
0,1-----0,4mol
nFe3O4=\(\dfrac{23,2}{232}\)=0,1 mol
=>VH2=0,4.22,4=8,96l
\(n_{Fe_3O_4}=\dfrac{23,2}{232}=0,1\left(mol\right)\\ 4H_2+Fe_3O_4\rightarrow\left(t^o\right)3Fe+4H_2O\\ n_{H_2}=4.n_{oxit}=4.0,1=0,4\left(mol\right)\\ \Rightarrow V_{H_2\left(đktc\right)}=0,4.22,4=8,96\left(l\right)\)