Prepare Solution With pH = 3.51

Question

A physician wishes to prepare a buffer solution at pH = 3.51 that efficiently resists changes in pH yet contains only small concentrations of the buffering agents.

Which of the following weak acids, together with its sodium salt, would be the best to use?

(i) m-chlorobenzoic acid, Ka = 1.04 × 10^-4
(ii) p-chlorocinnamic acid, Ka = 3.89 × 10^-5
(iii) 2,5-dihydroxybenzoic acid, Ka = 1.08 × 10^-3
(iv) acetoacetic acid, Ka = 2.62 × 10^-4

Give a concise explanation for your choice.

Summary

The question belongs to Chemistry and it discusses about choosing a weak acid together with sodium salt that can be used to prepare a solution with pH = 3.51.

Total Word Count 98