What is the pH at which glycine, an amino acid, exists as a zwitterion with the maximum number of intramolecular hydrogen bonds?
1.6
3.0
6.0
9.6
At a pH of 9.6, glycine exists as a zwitterion with the maximum number of intramolecular hydrogen bonds. At lower pH, the group is protonated and at higher pH, the
group is deprotonated, leading to fewer intramolecular hydrogen bonds.