A buffer is 0.282 M C₆H₅COOH(aq) and 0.282 M Na(C₆H₅COO)(aq). Calculate the pH after the addition of 0.150 moles of nitric acid to 1.0 L of the buffer. For C₆H₅COOH, pKa = 4.20. A) 3.69 B) 4.20 C) 4.71 D) 3.87

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Quizplus · Accepted Answer

The correct answer is A because the addition of nitric acid will consume some of the acetate ions in the buffer, causing the pH to decrease. The new pH can be calculated using the Henderson-Hasselbalch equation:pH = pKa + log([A-]/[HA])where [A-] is the concentration of the acetate ion and [HA] is the concentration of the acetic acid.After the addition of nitric acid, the concentration of the acetate ion will decrease and the concentration of the acetic acid will increase. Therefore, the pH will decrease.

A Buffer Is 0