In Chemistry, Transition Elements and Coordination Chemistry, Periodic Table and Representative elements take 3 questions slot. Thermodynamics and Gaseous state, Atomic structure, Chemical Bonding, Chemical and Iconic Equilibrium, Solid State and Surface Chemistry and Nuclear Chemistry and Environment get 2 questions slot each and the remaining get 1 question each. Now this is based on previous years' papers and this might change as this pattern is not fixed. So you need to prepare keeping that in mind and few books that can  help you are:

NCERT Books

Modern Approach to Chemical Calculations by R.C Mukherjee

Organic Chemistry by OP Tandon

Concept of Physical Chemistry by P Bahadur

Concise Inorganic Chemistry by J D Lee

Physical Chemistry by P.W Atkins

Organic Chemistry by Morrison and Boyd