What is the pH of 10^-7 M - solution at 25°C? — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

At this very low concentration, contribution from water auto-ionization is significant. Solving (10^-7 + x)x = 10^-14 gives x = 0.618 * 10^-7 M. Total [H+] = 1.618 * 10^-7 M. pH = -log(1.618 * 10^-7) = 6.79.