hi,

yes pcb background student may opt for bsc in chemistry courses in certain university, but the rules are different for some university like Central university of india , calcutta university, jadavpur university, presidency college, st xaviours strictly give admission in bsc chemistry honors with math back ground student. so you need to carefully check the eligibility criteria before applying in any college. another disadvantage not to having math in 10+2 course is iits does not provide msc admission to candidates who does not have mathematics in 12th course.

hope you may understand.