Metal-metal bonding is more frequent in 4d or 5d series than in 3d series due to : — d and f Block Elements Chemistry Question

💡 Solution & Explanation

Step 1: When steam is passed over red-hot iron, a reversible oxidation-reduction reaction occurs. Step 2: Iron reacts with water (steam) to form magnetic iron oxide (Fe3O4) and hydrogen gas (H2): 3Fe + 4H2O(g) -> Fe3O4 + 4H2. Step 3: Thus, the substances formed are Fe3O4 and H2, corresponding to option (b).