1. The carboxylic acid group of an amino acid has a pKa ofapproximately 2. However, carboxylic acids like benzoic acid andacetic acid have pKas in the range of 4-5 pKa units. Explain whythe carboxylic acid of an amino acid is more acidic.
2. Consider the amino acid arginine: a. At physiological pH (pH= 7.4), what is the predominant form in solution? b. What percentof the carboxylic acid group is ionized at this pH? c. What percentof the amino group is ionized at this pH?
