A buffer solution is prepared by mixing 82.3 mL of 0.0329 M butanoic acid with 21.4 mL of 0.661 M sodium butanoate.

A table of pKa values 4.82

1. Calculate the pH (to two decimal places) of this solution.

Assume the 5% approximation is valid and that the volumes are additive.

2. Calculate the pH (to two decimal places) of the buffer solution after the addition of 13.9 mL of a 0.0525 M solution of hydrochloric acid to the existing buffer solution.

Assume the 5% approximation is valid and that the volumes are additive.