Para-aminobenzoic acid has two ionizable groups. One is a carboxylic acid that ionizes through loss of a proton thereby forming a charged para-aminobenzoic acid carboxylate anion, and the other is an amine connected to an aromatic (benzene) ring that ionizes by accepting an H+ to form a positively charged ammonium ion. The pk of the carboxylic acid is 4.9 and the pk of the amino group is 2.5. Assume that the intracellular pH within a bacterial cell is 7.0. H H O-H pk = 2.5 Which of the following structures correctly depicts how most of the para-aminobenzoic acid is ionized at pH 7? A. B. H + H-N- H C. H H. + H-N- H N- H O-H pK₂ = 4.9 D. X o o O-H

Para-aminobenzoic acid has two ionizable groups. One is a carboxylic acid that ionizes through loss of a proton thereby forming a charged para-aminobenzoic acid carboxylate anion, and the other is an amine connected to an aromatic (benzene) ring that ionizes by accepting an H+ to form a positively charged ammonium ion. The pk of the carboxylic acid is 4.9 and the pk of the amino group is 2.5. Assume that the intracellular pH within a bacterial cell is 7.0. H H O-H pk = 2.5 Which of the following structures correctly depicts how most of the para-aminobenzoic acid is ionized at pH 7? A. B. H + H-N- H C. H H. + H-N- H N- H O-H pK₂ = 4.9 D. X o o O-H

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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