A physician wishes to prepare a buffer solution at pH = 3.82 that efficiently resists changes in pH yet contains only small concentrations of the buffering agents. Determine which one of the following weak acids, together with its sodium salt, would probably be best to use: m-chlorobenzoic acid, Ka= 1.04 × 10-4 ; p-chlorocinnamic acid, Ka=3.89 × 10-5 ; 2,5-dihydroxybenzoic acid, Ka = 1.08 ×10-3 ; or acetoacetic acid, Ka= 2.62 × 10-4 . Explain.

A physician wishes to prepare a buffer solution at pH = 3.82 that efficiently resists changes in pH yet contains only small concentrations of the buffering agents. Determine which one of the following weak acids, together with its sodium salt, would probably be best to use: m-chlorobenzoic acid, Ka= 1.04 × 10-4 ; p-chlorocinnamic acid, Ka=3.89 × 10-5 ; 2,5-dihydroxybenzoic acid, Ka = 1.08 ×10-3 ; or acetoacetic acid, Ka= 2.62 × 10-4 . Explain.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter15: Additional Aqueous Equilibria

Section: Chapter Questions

Problem 15.ACP

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