An acetic acid buffer containing 0.50 M CH₃COOH and 0.50 M CH₃COONa has a pH of 4.74. What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer? A)4.77 B)4.71 C)4.68 D)4.62 E)None of these choices are correct.

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Quizplus · Accepted Answer

The buffer solution resists changes in pH. When HCl is added, it reacts with the acetate ion (CH3COO-) to form acetic acid (CH3COOH), slightly increasing the concentration of acetic acid and decreasing the concentration of acetate ion. Using the Henderson-Hasselbalch equation, the pH change is minimal, resulting in a pH of approximately 4.71.

An Acetic Acid Buffer Containing 0