JEE Main Chemistry Chapter Weightage & Important Topics 2027
Every chapter ranked by how many questions it contributed across 16 past JEE Main Paper-1 shift papers (2022–2025), with the expected number of questions in a 25-question Chemistry section. Focus your prep top-down.
Chapter-wise weightage
| # | Chapter | Expected in paper | Weightage |
|---|---|---|---|
| 1 | Organic Compounds Containing Oxygen | ~2.2 | ★★★★★ |
| 2 | Coordination Compounds | ~2.0 | ★★★★☆ |
| 3 | Chemical Bonding and Molecular Structure | ~1.7 | ★★★★☆ |
| 4 | Redox Reactions and Electrochemistry | ~1.6 | ★★★☆☆ |
| 5 | d- and f- Block Elements | ~1.5 | ★★★☆☆ |
| 6 | p- Block Elements | ~1.4 | ★★★☆☆ |
| 7 | Solutions | ~1.3 | ★★★☆☆ |
| 8 | Hydrocarbons | ~1.3 | ★★★☆☆ |
| 9 | Organic Compounds Containing Nitrogen | ~1.3 | ★★★☆☆ |
| 10 | Some Basic Principles of Organic Chemistry | ~1.2 | ★★★☆☆ |
| 11 | Equilibrium | ~1.1 | ★★★☆☆ |
| 12 | Chemical Kinetics | ~1.1 | ★★★☆☆ |
| 13 | Purification and Characterisation of Organic Compounds | ~1.1 | ★★☆☆☆ |
| 14 | Atomic Structure | ~1.1 | ★★☆☆☆ |
| 15 | Chemical Thermodynamics | ~1.1 | ★★☆☆☆ |
| 16 | Biomolecules | ~1.0 | ★★☆☆☆ |
| 17 | Some Basic Concepts in Chemistry | ~1.0 | ★★☆☆☆ |
| 18 | Organic Compounds Containing Halogens | ~0.7 | ★★☆☆☆ |
| 19 | Principles Related to Practical Chemistry | ~0.7 | ★★☆☆☆ |
| 20 | Classification of Elements and Periodicity in Properties | ~0.7 | ★☆☆☆☆ |
Top 20 most-asked topics
| # | Topic | Chapter | Times asked | Importance |
|---|---|---|---|---|
| 1 | various quantum numbers (principal, angular momentum and magnetic quantum numbers) and their significance | Atomic Structure | 2× | ★★★★★ |
| 2 | Stoichiometry with a limiting reagent | Some Basic Concepts in Chemistry | 1× | ★★★☆☆ |
| 3 | Bohr model: radius of orbit proportional to n2 | Atomic Structure | 1× | ★★★☆☆ |
| 4 | Free (Joule) expansion into vacuum, work, heat and internal energy | Chemical Thermodynamics | 1× | ★★★☆☆ |
| 5 | Henry's law constant and its variation with temperature | Solutions | 1× | ★★★☆☆ |
| 6 | Raoult's law for ideal solutions of two volatile liquids | Solutions | 1× | ★★★☆☆ |
| 7 | Solubility product, ionic product and precipitation condition | Equilibrium | 1× | ★★★☆☆ |
| 8 | VSEPR, hybridization, lone pairs and dipole moment | Chemical Bonding and Molecular Structure | 1× | ★★★☆☆ |
| 9 | Anomalous periodic trends in group 17 (halogens) | p- Block Elements | 1× | ★★★☆☆ |
| 10 | Anomalous atomic and ionic radii of Al and Ga (group 13) | p- Block Elements | 1× | ★★★☆☆ |
| 11 | Crystal field theory: spin state, splitting energy vs pairing energy | Coordination Compounds | 1× | ★★★☆☆ |
| 12 | Identify elements from clues then apply VSEPR to find shape (XeOF4) | Chemical Bonding and Molecular Structure | 1× | ★★★☆☆ |
| 13 | Qualitative analysis: potassium ferrocyanide tests for cations | Principles Related to Practical Chemistry | 1× | ★★★☆☆ |
| 14 | Quantitative combustion analysis, percentage composition and empirical formula | Purification and Characterisation of Organic Compounds | 1× | ★★★☆☆ |
| 15 | Stability of free radicals (allylic, propargylic, primary, vinylic) | Some Basic Principles of Organic Chemistry | 1× | ★★★☆☆ |
| 16 | Aromaticity and Huckel's (4n+2) rule for charged ring systems | Hydrocarbons | 1× | ★★★☆☆ |
| 17 | Dehydrohalogenation, halogenation, alkyne formation and Markovnikov hydration of alkynes | Hydrocarbons | 1× | ★★★☆☆ |
| 18 | Relative reactivity of carboxylic acid derivatives towards hydrolysis | Organic Compounds Containing Oxygen | 1× | ★★★☆☆ |
| 19 | Reactions of phenolic aldehydes; requirement of alpha-hydrogen for aldol condensation | Organic Compounds Containing Oxygen | 1× | ★★★☆☆ |
| 20 | Basic strength of amines in aqueous solution (inductive, steric, solvation) | Organic Compounds Containing Nitrogen | 1× | ★★★☆☆ |
Weightage = recency-weighted question count (recent shifts count for more). "Expected/paper" projects each chapter's share onto a 25-question section — a planning guide, not a guarantee.