Yes of course,

You can indeed do MCA after BSc Physics/Chemistry/Maths Some Universities ask for Maths at the 12th level some ask for Maths up to Graduation level.

Generally Eligibility for MCA is any graduate who has passed or appearing for the final year degree examination in any discipline (Science, Commerce, Arts, Engineering or any approved University) is eligible to apply. Candidates must have mathematics as a subject in their 10+2 course or any one year of graduation.