Hydrogen can be prepared by the action of dil. H₂SO₄ on

Hydrogen can be displaced by the metals that have less reduction potential than H ion. Therefore, gold (Au) copper (Cu) and mercury (Hg) can’t be used to prepare hydrogen due to its high reduction potential. Hence, Iron is used to prepare hydrogen by using dil. 2 4 H SO . 2 4 4 2 H SO aq Fe s FeSO aq H gas →