# The calculation of the isoelectric point (pI) of an amino acid. General method, step by step solutions to the problems, and definitions of concepts/terms provided.

Calculate the isoelectric point (pI) of each of the following amino acids

(a) glycine

(b) glutamic acid

(c) arginine

#### Solution Preview

...o: Assign pKa values (provided from a textbook) to each ionization step.

Step three: Calculate pI (see below)

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(a) Glycine

Glycine has 2 pKa values, assigned as follows.

pKa1 = 2.4, pKa2 = 9.8

The form of glycine that has a "net charge of zero" is ...