What would be the pH of an ammonia solution if the pH of acetic acid solution of same strength is 3. — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

Because the dissociation constants ($K_a$ and $K_b$) and concentrations are identical, the degree of dissociation for both solutions is exactly the same. For the acetic acid solution, $\text{pH} = 3.2$, meaning $[\text{H}^+] = 10^{-3.2}$. Therefore, the ammonia solution will produce an identical concentration of hydroxide ions: $[\text{OH}^-] = 10^{-3.2}$, which means its $\text{pOH} = 3.2$. The pH is $14 - \text{pOH} = 14 - 3.2 = 10.8$.