Question 4

(Multiple Choice)

Citric acid is a triprotic acid with three carboxylic acid groups having pKa values of 3.1,4.8,and 6.4.If a solution of citric acid has a pH of 5.5,what can be said about the predominant protonation state of the citric acid?


A)1 carboxylic acid group is deprotonated,2 are protonated
B)2 carboxylic acid groups are deprotonated,1 is protonated
C)all 3 carboxylic acid groups are deprotonated
D)all 3 carboxylic acid groups are protonated
E)the protonation state cannot be determined

Answer