What is the isoelectric point of serine (pK_a of $\alpha$-CO₂H, 2.21; pK_a of $\alpha$-NH₂, 9.15)?

Question

Quizplus · Accepted Answer

The isoelectric point (pI) of a molecule is the pH at which it carries no net electrical charge. It can be calculated by averaging the pKa values of the amino and carboxyl groups in the molecule. For serine, the amino group has a pKa of 2.21 and the carboxyl group has a pKa of 9.15. Therefore, the pI of serine can be calculated as (2.21 + 9.15)/2 = 5.68. Hence, the correct answer is A.

What Is the Isoelectric Point of Serine (PKa Of α\alphaα -CO2H, 2

What Is the Isoelectric Point of Serine (PK_a Of $\alpha$ -CO₂H, 2