Chapter 14, Problem 30QAP

A buffer is made up of 239 mL of 0.187 M potassium hydrogen tartrate (KHC₄H₄O₆) and 137 mL of 0.288 M potassium tartrate (K₂C₄H₄O₆). K_a for is (H₂C₄H₄O₆) $4.55\times {10}^{-5}$.

Assuming volumes are additive, calculate

(a) the pH of the buffer.

(b) the pH of the buffer after adding 0.0250 mol of HCI to 0.376 L of the buffer.

(c) the pH of the buffer after adding 0.0250 mol of KOH to 0.376 L of the buffer.