CBSE Class 12 Chemistry chapter-wise weightage
What the 2023–2026 board papers actually asked, chapter by chapter.
CBSE gives marks to units, not to chapters. Each unit below shows the marks CBSE’s 2025-26 syllabus gives it, and under it how the marks in the 2023–2026 papers actually split between its chapters.
| Chapter | 2023 | 2024 | 2025 | 2026 | Average |
|---|---|---|---|---|---|
| SolutionsCBSE: 7 of 70 marks (10.0%) · in the papers: 9.6% | |||||
| Solutions | 9.8% | 9.6% | 9.6% | 9.2% | 9.6% |
| ElectrochemistryCBSE: 9 of 70 marks (12.9%) · in the papers: 11.3% | |||||
| Electrochemistry | 10.7% | 10.9% | 13.2% | 10.5% | 11.3% |
| Chemical KineticsCBSE: 7 of 70 marks (10.0%) · in the papers: 9.8% | |||||
| Chemical Kinetics | 9.4% | 10.9% | 9.5% | 9.2% | 9.8% |
| d -and f -Block ElementsCBSE: 7 of 70 marks (10.0%) · in the papers: 9.7% | |||||
| The d-and f-Block Elements | 11.7% | 8.0% | 9.0% | 10.1% | 9.7% |
| Coordination CompoundsCBSE: 7 of 70 marks (10.0%) · in the papers: 10.6% | |||||
| Coordination Compounds | 9.8% | 9.8% | 11.1% | 11.6% | 10.6% |
| Haloalkanes and HaloarenesCBSE: 6 of 70 marks (8.6%) · in the papers: 9.0% | |||||
| Haloalkanes and Haloarenes | 9.4% | 9.5% | 7.7% | 9.2% | 9.0% |
| Alcohols, Phenols and EthersCBSE: 6 of 70 marks (8.6%) · in the papers: 8.4% | |||||
| Alcohols, Phenols and Ethers | 8.0% | 9.5% | 8.6% | 7.4% | 8.4% |
| Aldehydes, Ketones and Carboxylic AcidsCBSE: 8 of 70 marks (11.4%) · in the papers: 9.9% | |||||
| Aldehydes, Ketones and Carboxylic Acids | 11.0% | 9.1% | 10.8% | 8.7% | 9.9% |
| AminesCBSE: 6 of 70 marks (8.6%) · in the papers: 9.9% | |||||
| Amines | 8.5% | 10.4% | 9.9% | 10.8% | 9.9% |
| BiomoleculesCBSE: 7 of 70 marks (10.0%) · in the papers: 11.9% | |||||
| Biomolecules | 11.6% | 12.4% | 10.5% | 13.2% | 11.9% |
How this is counted
From all 1,255 questions in the 2023–2026 CBSE Class 12 Chemistry papers we hold: every region and set, with a question printed in several sets counted once. A chapter’s share is its marks divided by all the marks of that year’s questions, and the average gives each year equal weight. These are observed shares, not an official CBSE weightage. 2022 is left out: it was the Term-II exam, which covered only part of the syllabus (see the 2022 paper).
Unit marks are CBSE’s own, from the 2025-26 syllabus. Where CBSE groups units under one figure, so does this table.