A student prepares a 0.050 mol dm−30.050\text{ mol dm}^{-3}0.050 mol dm−3 aqueous solution of benzoic acid, C6H5COOH\text{C}_6\text{H}_5\text{COOH}C6H5COOH, to use as a preservative. At 298 K298\text{ K}298 K, the acid dissociation constant, KaK_{\text{a}}Ka, of benzoic acid is 6.48×10−5 mol dm−36.48 \times 10^{-5}\text{ mol dm}^{-3}6.48×10−5 mol dm−3.
Calculate the percentage dissociation of benzoic acid in this solution.