Most Important Chapters — Class 12 Chemistry
Class 12 Chemistry theory is 70 marks, split across Physical, Inorganic and Organic. Organic chapters together dominate.
TL;DR: Class 12 Chemistry theory is 70 marks, split across Physical, Inorganic and Organic. Organic chapters together dominate.
Written & reviewed by the Syllab.in Academic Team (CBSE/NCERT subject experts) · Updated
Class 12 Chemistry theory is 70 marks, split across Physical, Inorganic and Organic. Organic chapters together dominate.
Class 12 Chemistry — Unit-wise Marks Weightage
CBSE Board — 70 marks in theory, listed heaviest first so you can see where your revision time actually earns marks.
| Unit | Marks | Share | What to focus on |
|---|---|---|---|
| Organic (Haloalkanes → Amines, Biomolecules) | 28 | 40% | Reaction mechanisms and named reactions — the biggest block; practise conversions. |
| Electrochemistry & Chemical Kinetics | 16 | 23% | Nernst equation, rate laws — numerical-heavy and scoring. |
| d- & f-Block + Coordination Compounds | 14 | 20% | Inorganic — colour, magnetism, IUPAC naming, isomerism. |
| Solutions | 7 | 10% | Colligative properties numericals. |
| Biomolecules | 5 | 7% | Carbohydrates, proteins — pure recall marks. |
How to Use This Weightage
Work down the table rather than through the textbook in order. Organic (Haloalkanes → Amines, Biomolecules) and Electrochemistry & Chemical Kinetics alone account for 44 of 70 marks, so a week spent there moves your score further than a week spent on the last three units combined. Once the heavy units are secure, the lighter ones are usually short and formula-driven, which makes them efficient to finish last.
Treat the tips in the final column as the specific sub-topics examiners return to. They are where the marks in each unit actually sit.
Frequently Asked Questions
Which chapters carry the most marks in Class 12 Chemistry?
Organic (Haloalkanes → Amines, Biomolecules) (28 marks) and Electrochemistry & Chemical Kinetics (16 marks) carry the most — 44 of 70 between them. Securing these two before anything else is the single highest-return decision in your revision plan.
What is the total marks for Class 12 Chemistry?
CBSE Board carries 70 marks in theory. The unit-wise split above accounts for all of them.
Should I skip the low-weightage units?
No. The smallest units here are worth 5 marks, which is more than the gap between most grade boundaries, and they are usually the quickest to prepare. Order your revision by weightage; do not delete anything from it.