The mass of iron converted into Fe3O4 by the action of 18 g of steam is:
(Given: Molar mass of H, O and Fe are 1, 16 and 56 g mol-1 respectively)
Assume iron is present in excess. [2026]
(4)
Moles of steam=Given mass of H2OMolar mass of H2O
=18 g18 g mol-1=1 mol
3Fe(s)+4H2O(g)⟶Fe3O4(s)+4H2(g)
By stoichiometry:
nFe3=nH2O4⇒nFe3=14
nFe=34
Mass of Fe=Moles of Fe×Molar mass of Fe
=34×56 g=42 g