Question

$K_a$ for $\text{CH}_3 \text{COOH}$ is $1.8 \times 10^{-5}$ and $K_b$ for $\text{NH}_4 \text{OH}$ is $1.8 \times 10^{-5}$. The pH of ammonium acetate solution will be:

Answer 1

The pH is given by:

$\text{pH} = \frac{pK_a + pK_b}{2}$

Since $pK_a = pK_b$,

$\text{pH} = \frac{7 + 7}{2} = 7$