CBSE Class 12 Chemistry Important Questions 2026-27 with Solutions PDF

Class 12 Chemistry requires consistent practice to score well in board exams. Based on previous years' papers, students need to prepare for different question types, including numericals, named reactions, and reasoning-based questions. 

Practising CBSE Class 12 Chemistry Important Questions helps you understand the CBSE exam pattern, strengthen conceptual understanding, and develop answer writing skills. 

This guide gives you detailed, chapter-wise important question PDFs with solutions for all 10 chapters, along with the 2026-27 assessment format, mark distribution, and practical advice to prepare effectively as per CBSE guidelines.

Download CBSE Class 12 Chemistry Important Questions PDF 2026-27 

CBSE does not officially release chapter-wise important questions for Class 12 Chemistry. At Educart, we have compiled Important Questions with solutions for all 10 chapters in PDF format to help you prepare for board exams. You can download the PDFs for free by clicking the download button and completing OTP verification.

Understand the Exam Pattern of CBSE Class 12 Chemistry 2026-27

The CBSE Class 12 Chemistry exam (Subject Code 043) carries 100 marks, with 70 marks for the theory exam and 30 marks for practicals. The theory paper consists of 33 compulsory questions divided into 5 main sections, to be completed in 3 hours. 

For 2026-27, CBSE has not introduced any major changes in the Class 12 Exam Pattern and follows the same 2024-25 assessment approach. There is no overall choice, but internal choices are provided in selected sections. 

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Unit-Wise Weightage for Class 12 Chemistry 

CBSE follows a unit-wise marking scheme rather than a chapter-wise one. Organic Chemistry (Ch6-10) is the largest section, worth 33 of 70 marks, followed by Physical Chemistry (23 marks) and Inorganic Chemistry (14 marks). Among individual chapters, Electrochemistry carries the highest weightage at 9 marks, and Aldehydes, Ketones, and Carboxylic Acids carry 8 marks.

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Chapter-Wise Important Topics for Class 12 Chemistry 2026-27

Below are key topics from each chapter to focus on while preparing for the Class 12 Chemistry board exam. Practice these alongside your regular NCERT revision to strengthen your understanding and exam readiness.

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A few topics such as Surface Chemistry, Isolation of Elements, Polymers, or Chemistry in Everyday Life are removed from the current theory syllabus. Always go through the official CBSE-prescribed syllabus for accurate chapter names and sample papers for the latest exam pattern.

CBSE Class 12 Chemistry Important Questions With Solutions 2026-27 

Scroll down for chapter-wise important questions with answers for CBSE Class 12 Chemistry 2026-27. Take one chapter at a time, and attempt each question on your own before referring to the solution. Follow the CBSE marking scheme to evaluate your answer and track progress regularly.

‍Q1. What is the difference between crystalline and amorphous solids?

Ans. Crystalline solids have a regular and repeating arrangement of particles, sharp melting points, and definite geometrical shapes (example: NaCl, quartz). Amorphous solids have irregular particle arrangement, no sharp melting point, and behave more like super-cooled liquids (example: glass, rubber).

Q2. State Raoult’s Law for a solution of volatile liquids.

Ans. Raoult’s Law states that the partial vapour pressure of each component in a solution is directly proportional to its mole fraction. Total vapour pressure is obtained by adding the partial pressures of the components. The law works best for ideal solutions.

Q3. What is the difference between electrolytic and galvanic cells?

Ans.  Galvanic cells convert chemical energy to electrical energy spontaneously, while electrolytic cells require an external source of electricity to bring about a chemical reaction. In galvanic cells, oxidation occurs at the anode and reduction at the cathode; in electrolytic cells, the polarity is reversed because current is forced.

Q4. Define Kohlrausch’s Law.

Ans. Kohlrausch’s Law states that at infinite dilution, the molar conductivity of an electrolyte is equal to the sum of the individual contributions of its ions. It is used to calculate molar conductivity of weak electrolytes.

Q5. What is the order of a reaction?

Ans. Order is the sum of the powers of the concentration terms in the rate law. It is determined experimentally and may be zero, fractional, or whole. Example: For rate = k[A]^2[B], order = 3.

Q6. Explain the effect of temperature on rate of reaction.

Ans. Rate increases with temperature because a higher fraction of molecules attain activation energy. According to the Arrhenius equation, rate constant increases exponentially with temperature, showing sensitivity of reactions to heat.

Q7. What is adsorption? Give one example.

Ans. Adsorption is the accumulation of molecules on the surface of a solid or liquid. Example: charcoal adsorbing gases like ammonia or nitrogen.

Q8. Why do transition metals form coloured compounds?

Ans. Transition metals have partially filled d orbitals. When light falls on them, electrons transition between d orbitals, producing characteristic colours.

Q9. Why do transition metals act as good catalysts?

Ans. They can change oxidation states easily and provide active surfaces for reactions. Adsorption of reactants on these surfaces lowers activation energy.

Q10. What is Werner’s theory?

Ans. Werner proposed that metal ions exhibit two types of valencies: primary valency (ionisable) and secondary valency (non-ionisable). Secondary valency determines the geometry of the complex.

Q11. What is the difference between a ligand and a coordination number?

Ans. A ligand donates a pair of electrons to the central metal ion. Coordination number refers to the number of ligand donor atoms attached to the metal.

Q12. Why do haloalkanes undergo nucleophilic substitution easily?

Ans.  Carbon halogen bonds are polar because halogens are electronegative. This creates a partial positive charge on carbon, making it vulnerable to nucleophilic attack.

Q13. Why is phenol more acidic than alcohol?

Ans. Phenoxide ion formed after losing H+ is stabilised by resonance, which alcohols lack. This stabilization increases acidic strength of phenol.

Q14. What is the mechanism of nucleophilic addition in aldehydes?

Ans. The carbonyl carbon is partially positive due to C=O polarity. Nucleophile attacks this carbon, resulting in breaking of the pi bond. Protonation follows, giving additional products.

Q15. What is the Hoffmann bromamide degradation reaction?

Ans. In this reaction, amides react with bromine in the presence of base to form amines with one carbon less. It is useful for shortening carbon chains.

Q16. What are reducing sugars? Give examples.

Ans. Reducing sugars contain free aldehyde or keto groups capable of reducing reagents. Examples: glucose, fructose, maltose.

Q17. What is denaturation of proteins?

Ans. Denaturation is the loss of secondary and tertiary structure due to heat, acids, or chemicals. The primary structure remains intact. Example: curdling of milk.

Q18. What is the difference between addition and condensation polymers?

Ans. Addition polymers form by repeated addition of monomers without loss of molecules (example: polyethylene). Condensation polymers form by combining monomers with elimination of small molecules like water (example: nylon-6,6).

Q19. What are analgesics?

Ans. Analgesics are drugs that reduce pain without causing unconsciousness.
Examples include aspirin and paracetamol.

Q20. What are food preservatives?

Ans. Food preservatives prevent spoilage by inhibiting microbial growth. Common examples include sodium benzoate and salts of sorbic acid.

EXTRA QUESTIONS FOR PRACTICE 

Q1. State and explain Henry’s Law. Mention its two important applications.

Q2. Define the term molar conductivity. How does it vary with concentration for strong and weak electrolytes?

Q3. Derive the integrated rate equation for a first-order reaction.

Q4. Write the general electronic configuration of d-block elements. Why do they form colored compounds?

Q5. Explain the crystal field splitting in an octahedral complex with a labeled diagram.

Q6. Distinguish between SN1 and SN2 reactions with suitable examples.

Q7. Write short notes on (a) Cannizzaro reaction (b) Hoffmann bromamide reaction.

Q8. Define biomolecules. Classify carbohydrates and give one example of each type.

Q9. Explain the preparation and properties of ethanoic acid.

Q10. What are lanthanoids? Mention two characteristic properties of lanthanoids.

Which is the Right Book for Class 12 Chemistry Important Questions

The right Important Question Book for Class 12 Chemistry combines quick revision notes, solved examples, and practice papers in one place. That’s where Educart provides students with a carefully curated Class 12 Chemistry Question Bank. They ensure every question is fully aligned with the revised 2026-27 curriculum and includes key question types to support board exam preparation.

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Tips to Use Chemistry Important Questions for 2027 Board Exams

Students should first build their basics using the NCERT textbook and understand the exam format through class 12 chemistry sample question paper. Once the basics are clear, strengthen your preparation by practising exam-oriented CBSE Class 12 Chemistry Important Questions.

1. Start with NCERT: Read each chapter and do all the in-text and exercise questions. The NCERT Exemplar for Class 12 Chemistry is perfect for additional practice.
2. Physical Chemistry (Chapters 1-3): Make a one-page cheat sheet for formulas like the Nernst equation, the Arrhenius equation, half-life, and colligative properties. Since calculators aren’t allowed, solve all numericals by hand. 
3. Inorganic Chemistry (Chapters 4-5): Make short notes about color, magnetism, shape, and coordination number. Memorise the key equations for KMnO₄ and K₂Cr₂O₇ reactions.
4. Organic Chemistry (Chapters 6-9): Note down all reactions in place, with reagent, conditions, and product for every named reaction. Draw each step of the mechanisms. 
5. Case-based and assertion-reason questions: Carefully read the passage or graph twice, using its data in your answer. For assertion-reason, check each statement on its own, then see if the reason really explains the assertion.
6. Full papers: Solve the official sample paper and previous years' paper class 12 chemistry under exam conditions. Cross-check your answers with the marking scheme and revise the ones you often make mistakes on.

Additional Practice Resources for Class 12 Chemistry Board Preparation

After completing chapter-wise Important Questions, use these books to practice exam-style questions, revise key concepts, and prepare effectively for the 2027 board examinations.

FAQs

Q1. What are the most important chapters in Class 12 Chemistry 2026-27?

Ans. The most important chapters for Class 12 Chemistry are Electrochemistry (9 marks) and Aldehydes, Ketones and Carboxylic Acids (8 marks). Organic Chemistry (33 of 70 marks) is the largest section.

Q2. What is the paper pattern for CBSE Class 12 Chemistry 2026-27?

Ans. CBSE has not confirmed any major changes in the paper pattern this year. The theory paper still holds 70 marks with 33 compulsory questions across five sections (A to E). The internal assessment/practicals carry 30 marks.

Q3. How can I download CBSE Class 12 Chemistry important questions PDF with solutions?

Ans. You can easily download chapter-wise important Qs PDFs for free from the table provided above on this page. An OTP verification is required before downloading.

Q4. Does the Class 12 Chemistry board exam have case-based questions?

Ans. Yes, Section D contains 2 case-based or data-driven questions of 4 marks each. Section A also contains assertion-reason questions.

Q5. Can I use a calculator in the Class 12 Chemistry board exam 2027?

Ans. No, CBSE doesn't permit calculators or log tables, so ensure you practise numericals without relying on a calculator. Polymers and Chemistry in Everyday Life are examined only formatively and are not a part of the 70-mark board paper.