Yes, colleges can rescind your acceptance if you drop AP Chemistry. IMO if you can complete the class and keep your grade a C or better that would be the best course of action.
I would email and ask permission from each admissions office you have an acceptance from to drop the class BEFORE you actually drop it. If a college admission office agrees to allow you to drop AP Chem and keep you admission offer be sure to get it in writing.
You also need to inform any colleges you are waiting for an answer from that you will be dropping the course.