Chemistry Question on preparation of dihydrogen

Question

Hydrogen can be prepared by the action of dil $H_{2}SO_{4}$ on

Answer 1

Solution

Hydrogen cannot be prepared by the action of dil. $H _{2} SO _{4}$ on copper or mercury as these two metals cannot displace hydrogen from acids. Action of dil. $H _{2} SO _{4}$ on $Pb$ stops after some time due to the formation of insoluble $PbSO _{4}$ . Only iron reacts rapidly with dil. $H _{2} SO _{4}$ to give $H _{2}$ .