<p>Yes, there is often a particular order in which you must take courses in college. Except for introductory level classes, courses will have pre-reqs or co-reqs–meaning that you must take another course first before enrolling (pre-req) or be concurrently enrolled in a certain class (co-req).</p>
<p>With only a 3 in AP chem (equivalent to a C in college), I would strongly suggest you consider re-taking general chemistry in college to firm up your foundational chemistry knowledge & understanding before advancing to Ochem. (Gen chem is a pre-req for ochem.)</p>