Question

If $p{K}_a$ of acetic acid and $p{K}_b$ of ammonium hydroxide are $4.76$ each. The $pH$ of ammonium acetate is

• A. 7
• B. less than 7
• C. more than 7
• D. zero.

Answer 1

Answer: (A)

pH of a salt of weak acid and weak base is
$pH=7+\frac{1}{2}p{K}_a-\frac{1}{2}p{K}_b$
$pH=7+\frac{1}{2}\times 4.76-\frac{1}{2}\times 4.76$