AP chemistry is supposed to cover material similar to the first semester or year of college general chemistry, although there may be variations in topics covered. In theory, completing the second semester of college general chemistry should cover most or all of the same topics that the AP chemistry exam tests.
However, you should expect that colleges will give you credit for at most one of the college course and AP credit, not both, since they are duplication of similar material. A high enough AP score may be useful if you attend a college that accepts AP scores but not college courses taken while in high school.
If you want to be a pre-med, be aware that college courses taken while in high school and their grades will be included in your pre-med application and GPA calculation.