(a) Natalia is asked to prepare a buffer solution at pH 5.40 by using one of the following acids : CH,COOH, K, -2.7 x 10-3 CH,OH, K, = 4.4 x 10-6 CH3CH2COOH, K, - 2.6 x 10-9 1. Which acid should Natalia choose? Suggest suitable salt to match with the acid. Justify your answer. II. By showing suitable equations, explain how buffer solution works in resisting pH changes. 18. Derive Handerson-hasselbalch equation for the above buffer system. (b) By using the following equation, discuss on how the equation can be used to explain both Bronsted-lowry and Lewis acid-base theory, NH, + H+ + NH4