Chapter 21, Problem 89E

Interpretation Introduction

Interpretation: The relative concentrations of each member of the relevant conjugate acid–base pair at pH = 2 and pH = 10. Calculate the pH at which glycine is neutral. Write the major equilibrium that is established in a solution of glycine at pH = 2 and at pH = 10.The $\text{p}{K}_{\text{a}}$ of the COOH group is 2.3 and the $\text{p}{K}_{\text{a}}$ of the $N{H}^{3+}$ group is 9.6.

Concept Introduction:

pH =6.0At pH = 2 (acidic), glycine acts as a base and gets protonated to form corresponding acid. Glycine is an amino acid molecule, with both amine and carboxylic acid functional group. In general, amino acids undergo intermolecular acid base reaction to form a zwitterion.