a
IE values indicate, that the metal belongs to Ist group since second IE is very high ( only one valence electron) Metal hydroxide will be of type, \(MOH\). \(\mathrm{MOH}+\mathrm{HCl} \rightarrow \mathrm{MCl}+\mathrm{H}_{2} \mathrm{O}\)

\((1mol)\) \((1 \mathrm{mol})\)

\(\mathrm{MOH}+\frac{1}{2} \mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow \frac{1}{2} \mathrm{M}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}\)

\((1mol) \)\(\left(\frac{1}{2} \mathrm{mol}\right)\)

So one mole of HCl required to react with one mole \(MOH.\)

So \(\frac{1}{2}\) mole of \(\mathrm{H}_{2} \mathrm{SO}_{4}\) required to react with one mole \(MOH.\)