Oxit: Fe_xO_y

Fe_xO_y+yH_2  $$\xrightarrow{t^o}$$  xFe+yH_2O

n_{Fe}={25,2}/{56}=0,45(mol)

Theo PT: n_{Fe_xO_y}={n_{Fe}}/x={0,45}/x(mol)

->M_{Fe_xO_y}=56x+16y={34,8}/{{0,45}/x}={232}/{3}x

->{64}/{3}x=16y

->x/y=3/4

->x=3;y=4

-> Oxit: Fe_3O_4

Fe_3O_4+4H_2  $$\xrightarrow{t^o}$$  3Fe+4H_2O

Theo PT: n_{H_2}=4/3n_{Fe}=0,6(mol)

->V_{H_2}=0,6.22,4=13,44(l)