MCAT Organic Chemistry Question 148: Answer and Explanation

Home > MCAT Test > MCAT organic chemistry practice tests

Test Information

Question: 148

13. What would be the charge of aspartic acid at pH 7?

  • A. Neutral
  • B. Negative
  • C. Positive
  • D. There is not enough information to answer the question.

Correct Answer: B

Explanation:

The amino acid in question is aspartic acid, which is an acidic amino acid because it contains an extra carboxyl group. At neutral pH, both of the carboxyl groups are ionized, so there are two negative charges on the molecule. Only one of the charges is neutralized by the positive charge on the amino group, so the molecule has an overall negative charge.

Previous       Next