Final answer:
The charge of an amino acid at any given pH depends on its isoelectric point. Amino acids are positively charged at pH lower than the isoelectric point and negatively charged at pH higher than the isoelectric point. At the isoelectric point, amino acids are electrically neutral.
Step-by-step explanation:
How to find the charge of an amino acid at any given pH?
The charge of an amino acid at any given pH depends on its isoelectric point (pl). The isoelectric point is the pH at which the positive and negative charges on the amino acid balance, making the molecule electrically neutral. To determine the charge of an amino acid at a specific pH, you need to compare the pH to the amino acid's isoelectric point.
For example, if the pH is lower than the isoelectric point, the amino acid will be positively charged. If the pH is higher than the isoelectric point, the amino acid will be negatively charged. At the isoelectric point, the amino acid will have no net charge and will be electrically neutral.