A 0.500 -L sample of $\mathrm{H}_{2} \mathrm{SO}_{4}$ solution was analyzed by taking a 100.0 -mL aliquot and adding 50.0 $\mathrm{mL}$ of 0.213 $\mathrm{M}$ NaOH. After the reaction occurred, an excess of $\mathrm{OH}^{-}$ ions remained in the solution. The excess base required 13.21 $\mathrm{mL}$ of 0.103 $\mathrm{M}$ $\mathrm{HCl}$ for neutralization. Calculate the molarity of the original sample of $\mathrm{H}_{2} \mathrm{SO}_{4}$ . Sulfuric acid has two acidic hydrogens.