CBSE Class 12 Board Exams 2026: The Chemistry paper is considered one of the most challenging in the Class 12 board examinations. A strong conceptual understanding is essential not only for scoring well in the board exams but also for performing in major entrance tests such as IIT JEE, NEET and various state-level entrance exams.
Students are advised to revise all important chapters thoroughly and practise the competency-focused questions released by the CBSE in its booklet. These questions are designed to familiarise students with the expected difficulty level of the upcoming exam. Those appearing for the 2026 board exams must go through all the questions, solve them section-wise and then verify their responses using the answer key attached to the practice paper. This will help them evaluate their preparation and identify areas that require improvement.
If students still face difficulty understanding certain chapters, they are encouraged to seek clarity from their teachers and revise the concepts again.
The Chemistry board exam is scheduled for February 28, and will be held from 10:30 AM to 1:30 PM.
Competency-Focused Practice Questions
Chemistry (Volume 2) | Grade 12
All questions in the booklet are aligned with the NCERT curriculum and have been created keeping in mind the learning outcomes essential for students to master. The booklet includes a mix of Free Response Questions (FRQs) and Multiple-Choice Questions (MCQs).
For MCQs, the options are crafted to test conceptual understanding and identify common errors or misconceptions that students may have.
Each question has been reviewed by experts to ensure appropriateness, conceptual accuracy, validity, language clarity and overall quality.
Here are a few questions students must practise to assess their preparation.
1. THE SOLID STATE
Given below are two statements labeled as Assertion (A) and Reason (R).
- Assertion (A): Frenkel defect is shown by compounds having a low r+/r- ratio and
- low dielectric constant.
- Reason (R): Frenkel defect maintains the neutrality of a crystal.
Select the most appropriate answer from the options given below:
- A. Both A and R are true and R is the correct explanation of A.
- B. Both A and R are true but R is not the correct explanation of A.
- C. A is true but R is false.
Which of the following statements is/are true?
(i) A non-stoichiometric compound Fe0.94O is formed when 18% of Fe2+ ions are
replaced by Fe3+ ions.
(ii) The conductivity of both intrinsic and extrinsic semiconductors is directly
proportional to temperature.
(iii) The BCC structure is the densest crystal structure.
A. i and iii
B. ii and iii
C. only i
D. i and ii
Free Response Question/ Subjective Question
Read the statements below and answer the question based on them:
-Graphite conducts electricity and is used as a lubricant.
-Diamond is hard and does not conduct electricity.
Explain these statements on the basis of the structure and bonding present in thesetwo solids
If the unit cell length of NaCl is a=563.1 pm and the density of NaCl is measured to\be 2.17×103 kg m−3. Calculate Z, the number of formula units in the unit cell.
(The atomic masses of sodium and chlorine are 22.99 and 35.45, respectively.)
SURFACE CHEMISTRY
Multiple Choice Questions
Which of the following is/are correct?
(i) At high pressure and temperature, physisorption may change to chemisorption
and the gas on a solid surface can't be retrieved.
(ii) Freezing point of the colloidal solution is lower than the true solution at the
same concentration of a solute.
A. only i
B. only ii
C. both i and ii
D. all- i, ii, and iii
Which of the following is/are correct for Freundlich's adsorption isotherm?
(i) the quantity of adsorbed particles on the adsorbent is directly proportional to k
(ii) the quantity of adsorbed particles on the adsorbent can be independent of p
(iii) the quantity of adsorbed particles on adsorbent is directly proportional to 1/n
A. ii only
B. ii and iii only
C. i and iii only
D. all- i, ii, and iii
CHEMICAL KINETIC
Multiple Choice Question
The reaction shown below illustrates the Haber process for manufacturing
ammonia:
In this reaction, molybdenum acts as a promoter, and iron is used as a catalyst.
Which of these is TRUE for the reaction?
A. Iron changes the activation energy of reaction and molybdenum increases
theefficiency of the catalyst.
B. Iron changes the equilibrium constant and molybdenum changes the Gibbs
energy ofthe reaction.
C. Iron changes the enthalpy of reaction and molybdenum changes the
equilibriumconstant.
D. Iron and molybdenum change the Gibbs energy of the reaction.
Which of the following can increase the rate of a chemical reaction?
P) increasing the temperature
Q) increasing the concentration of products
R) adding a catalyst
S) increasing the concentration of reactants
A. Q and S
B. P and Q
C. P, R, and S
D. All- P, Q, R, and S
ALDEHYDES, KETONES AND CARBOXYLIC ACIDS
Free Response Question/ Subjective Type
Tushar has a mixture of two powders one of which is an aldehyde and the other an alkane. Both the powders are insoluble in water. The two powders can be separated by a method based on a chemical property of aldehydes.
Describe the steps in this method to separate the two powder
A carbon compound of molecular formula C3H6O contains a ketone functional group.
Draw the structural formulae of two compounds having the same molecular formula as above but with a different functional group containing an oxygen atom
Access the full set of competency-based practice questions for the CBSE Class 12 Chemistry paper here.
