Separate solutions of NaW, NaX, NaY and NaZ, each of concentrations 0.1 M, has pH 7.0, 9.0, 10.0 and — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

The sodium salt of an acid undergoes anionic hydrolysis ($\text{A}^- + \text{H}_2\text{O} \rightleftharpoons \text{HA} + \text{OH}^-$) only if it comes from a weak acid. A higher pH means more hydrolysis, indicating a weaker parent acid. NaW has a pH of 7.0, meaning it does not hydrolyze. This implies its parent acid, HW, is a strong acid (like HCl). The others are weak acids. Thus, HW is the strongest.