Which of the following statement(s) is/are correct? — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

The pH of $10^{-8}\text{ M HCl}$ is slightly less than 7 because water auto-ionization cannot be neglected (A is incorrect). The conjugate base of $\text{H}_2\text{PO}_4^-$ is formed by removing one $\text{H}^+$, yielding $\text{HPO}_4^{2-}$ (B is correct). The auto-ionization of water is endothermic, meaning $K_w$ increases with temperature (C is correct). At the half neutralization point of a weak acid titration, $\text{pH} = pK_a$, not $pK_a/2$ (D is incorrect). Therefore, correct answer is B,C.