We’re being asked to **calculate the pH of a solution that has an acetic acid concentration of 0.050 M and a sodium acetate concentration of 0.075 M**.

A solution that contains a **weak acid** and its **conjugate base** is a **buffer solution**. The pH of a buffer solution can be determined using the **Henderson-Hasselbalch equation**.

$\overline{){\mathbf{pH}}{\mathbf{=}}{{\mathbf{pK}}}_{{\mathbf{a}}}{\mathbf{+}}{\mathbf{log}}{\mathbf{}}\mathbf{\left(}\frac{\mathbf{conjugate}\mathbf{}\mathbf{base}}{\mathbf{weak}\mathbf{}\mathbf{acid}}\mathbf{\right)}}$

**Given solution:**

The solution is composed of 0.050 M acetic acid and 0.075 M sodium acetate

• **acetic acid (CH _{3}COOH)** is a

• the anion in sodium acetate (NaCH

What is the pH of a solution that has an acetic acid concentration of 0.050 M and a sodium acetate concentration of 0.075 M?

A 4.92

B. 9.30

C. 7.50

D. 1.30

E. 1.12