The pH at which water is maximum dissociated at , is — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

The dissociation of water is given by $H_2O \rightleftharpoons H^+ + OH^-$. The addition of either an external acid (which adds $H^+$) or an external base (which adds $OH^-$) suppresses the self-dissociation of water due to the common ion effect. Therefore, water is maximally dissociated when it is pure and neutral, which at $25^\circ \text{C}$ corresponds to a pH of 7. Therefore, correct answer is B.