Hello,

first thing, no one knows how many questions will be asked and which chapters will be included for majority questions. it may happen from every chapter one question may be asked. so, it would be risky to narrow down the chapters to important ones based on previous year trend as there is no surety if they will be followed for current year.

In case, you are running out of time then here are some chapters where you can starting covering from where more frequent answers are asked:

Organic Chemistry

Biomolecules
Haloalkanes and Haloarenes
Hydrocarbons
Polymers
Alcohols, Phenols and Ethers
Aldehydes, Ketones and Carboxylic Acids
Organic compounds containing Nitrogen



Physical Chemistry:-

Thermodynamics
Equilibrium
Redox Reactions
Structure of Atom
Chemical Kinetics
Surface Chemistry
Classification of Elements and Periodicity in Properties
Chemical Bonding and Molecular Structure
States of Matter: Gases and Liquids
Electrochemistry


Inorganic Chemistry:-

Hydrogen
s-Block Elements
Solid State
Solutions
p-Block Elements (Group 15)
Group 16, Group 17 elements and Group 18 elements
d and f Block Elements
Coordination Compounds
properties of some important compounds

Hope it helps!