Answer:
3
Explanation:
At pH 3, the pentapeptide Ala-Glu-His-Val-Cys would contain two positively charged groups and one negatively charged group.
This is evident in that peptides have both carboxylic and amino groups.
Given that peptides have a certain amount of H⁺ and OH⁻ ions, it converts to zwitterions.
This conversion process is based on pKₐ and pKb of the acid and the base accordingly.
Therefore, they have two positively charged groups and one negatively charged grou
