Calculate the pH of a buffer solution containing 0.25 M acetic acid (Ka = 1.76 × 10⁻⁵) and 0.45 M sodium…

Question

Calculate the pH of a buffer solution containing 0.25 M acetic acid (Ka = 1.76 × 10⁻⁵) and 0.45 M sodium acetate.

ScanSolve AI Tutor · Accepted Answer

✅ Correct.

The solution correctly calculates the pH of the buffer using the Henderson-Hasselbalch equation.

The $\text{p}K_a$ is correctly calculated from the given $K_a$ value
$\text{p}K_a = -\log_{10}(1.76 \times 10^{-5}) \approx 4.754$
The Henderson-Hasselbalch equation is applied with the correct concentrations of the acid and its conjugate base
$\text{pH} = \text{p}K_a + \log_{10}\left(\frac{[\text{A}^-]}{[\text{HA}]}\right)$ $\text{pH} = 4.754 + \log_{10}\left(\frac{0.45 \text{ M}}{0.25 \text{ M}}\right)$ $\text{pH} = 4.754 + \log_{10}(1.8)$ $\text{pH} = 4.754 + 0.255$ $\text{pH} = 5.009$
The final pH is correctly rounded to two decimal places
$\text{pH} \approx 5.01$
The final answer is 5.01.

Calculate the pH of a buffer solution containing 0.25 M acetic acid (Ka = 1.76 x 10⁻⁵) and 0.45 M sodium acetate.