NTA Abhyas JEE Main2020ChemistryBiomoleculesPractice
What will be the nature of existence of an amino acid (containing one amino and one carboxylic acid group) in solution of pH < p K a 1 ?
Options
- AIt exists an anion
- BIt exists as cation
- CIt exists as zwitter ion
- DIt exists as neutral species with no charge
Correct answer
B. It exists as cation
Step-by-step solution
At low pH (acidic solution) C O O - ion acts as the base and accepts proton to form the cation. H 3 N + − C | R | H − C | | O − O − Zwitter ion → In acidic medium H 3 N + − C | R | H − C | | O − OH Cation