If you like Quantum Computation and related things, I would not suggest Chemistry, because you will need detailed studies of physics and math in such a way you probably will not have in a Chemistry course.
You can chose math, but you´ll need to be aware that what you will learn about physics is not too much during the graduation. If you want to study natural phenomena and quantum mechanics, I would suggest physics. But I must warn you that I´m being partial...
