If the titration curve shown below is for the amino acid glycine, at which point in the curve is the pI?
A) A
B) B
C) C
D) D

Question

If the titration curve shown below is for the amino acid glycine, at which point in the curve is the pI? 
A) A 
B) B 
C) C 
D) D

Quizplus · Accepted Answer

The pI of an amino acid is the pH at which the molecule carries no net charge. At point C on the titration curve, the glycine molecule is zwitterionic, meaning it contains both a positive and negative charge, resulting in a net charge of zero. Therefore, the pI of glycine is at point C.

If the Titration Curve Shown Below Is for the Amino