Question

The pH of a solution which is $0.1\text{M}$ sodium acetate and $0.01\text{M}$ acetic acid $({\text{pK}}_a=4.74)$ would be:

• A. $5.74$
• B. $4.74$
• C. $4.1$
• D. None of these

Answer 1

The correct option is A $5.74$

Given a solution which is $0.1\text{M}$ sodium acetate and $0.01\text{M}$ acetic acid. This is an acidic buffer solution.

${\text{pH = pK}}_a+\log \frac{\left[C{H}_{3}COONa\right]}{\left[C{H}_{3}COOH\right]}=4.74+\log \frac{0.1}{0.01}=4.74+1=5.74$

Hence, the pH of the buffer solution is $5.74$.