CBSE Class 12 Chemistry Important Questions: Chapter Wise Questions List

Overview: Preparing for CBSE Class 12 Chemistry can be challenging due to the broad syllabus. Check out some important questions for the CBSE Class 12 Chemistry exam along with solutions.

The chemistry paper in CBSE's Class 12 exams is not just about learning things by heart; it tests your conceptual clarity, analytical skills, and knowledge application. 

With a vast syllabus to cover, students often feel overwhelmed. Let's check the CBSE Class 12 Chemistry Important Questions with answers which will help you to focus your studies and build confidence for the board exams.

Download Free Study Materials for CBSE Class 12th by SuperGrads

Note: The video is for the 2024 cycle. However, the content is relevant for the 2025 exam cycle as well. Any changes will be updated here!

How to Prepare for CBSE Class 12 Chemistry Important Questions

Here's how to approach the important questions of chemistry CBSE Class 12 - 

• Conceptual Clarity: Instead of rote learning, focus on understanding the concepts. This will help answer both theoretical and application-based questions.
• Practice Regularly: Daily practice of numerical and chemical reactions will boost confidence and improve speed.
• Mind Maps: Create mind maps for each chapter. This helps in quick revision and consolidating the main ideas.
• Previous Years’ Papers: Analyzing past papers helps you understand the question pattern and gauge your preparation level.
• Mock Tests: Appear for multiple mock tests to practice time management and pinpoint your weaknesses.

Check Out: CBSE Syllabus for Class 12 Chemistry

Sample CBSE Class 12 Chemistry Important Questions

Chemistry important questions for CBSE class 12 are given below - 

Q1: Calculate the mass percentage of aspirin (C9H8O4) in acetonitrile (CH3CN) when 6.5g of C9H8O4 is dissolved in 450g of CH3CN. 

Answer: 

Mass % of a component = Mass of the component in the solution/ Total mass of solution * 100

= 6.5 / 6.5+450 * 100 

= 1.424%

Check Out: How to score 100 in Chemistry Class 12 CBSE

Q2: Calculate the amount of benzoic acid (C6H6COOH) required to prepare 250 ml of 0.15M solution in methanol. 

Answer: 

Molarity CM) = No of moles of solute / VColume of solution (Litre)

0.15=n/ 250

n=0.15*0.25

n=0.0375

Molarmass of benzoic acid = C6H5COOH

7*12+1*6+16*2

84+6+32=122g

Mass=n*M.M

0.0375*122=4.575g

Check Out: CBSE class 12 Chemistry Reference books

Q3: Define colligative properties. 

Answer:

Colligative properties are those of a solution that depend only on the number of solute particles and not on the nature of the solute. 

1. Relative lowering of vapour pressure
2. Elevation in boiling point
3. Depression at the freezing point
4. Osmosis and Osmotic pressure

Check Out: CBSE class 12 Chemistry Tips and Tricks

Q4: The position of -Br in the compound in CH3CH == CHC(Br)(CH3)2 can be classified as _. 

(i) Allyl

(ii) Aryl

(iii) Vinyl

(iv) Secondary 

Answer:

(i) Allyl

Q5: Polar solvents make the reaction faster as they: 

(i) Destabilize the transition state and decrease the activation energy.

(ii) Destabilize the transition state and increase the activation energy.

(iii) Stabilize the transition state and increase the activation energy.

(iv) Stabilize the transition state and decrease the activation energy.

Answer:

(iv) Stabilize the transition state and decrease the activation energy.

Check Out: CBSE class 12 Chemistry Marking scheme

Download PYPs with Solutions for CBSE Class 12th by SuperGrads

Q6: For a reaction nx+y->z, the reaction rate becomes twenty-seven times when the concentration of X is increased three times. What is the order of the reaction? 

(i) 2

(ii) 1

(iii) 0

(iv) 3

Answer:

(iv) 3

Q7: A reaction is found to be of second order with respect to the concentration of carbon monoxide. If the concentration of carbon monoxide is doubled, the rate of reaction will

(i) Triple

(ii) increase by a factor of 4

(iii) double

(iv) remain unchanged

Answer:

(ii) increase by a factor of 4

Check Out: CBSE 2023 Toppers Talk

Q8: Which of the following solutions has the highest osmotic pressure? 

(i) 1 M NaCl

(ii) 1 M NgCI2

(iii) 1 M Urea

(iv) I M Glucose

Answer:

(ii) 1 M NgCI2

Q9: The maximum amount of a solid solute that can be dissolved in a specified amount of a given liquid solvent does not depend upon the following: 

(i) Temperature

(ii) Nature of solute

(iii) Pressure

(iv) Nature of solvent

Answer:

(iii) Pressure

Check Out: CBSE Class 12 Applied Mathematics

Q10: In which of the following elements 5f orbitals are progressively filled?

(i) Alkaline earth metals

(ii) Actinoids

(iii) Lanthanoids

(iv) Transition elements

Answer:

(ii) Actinoids

Q11: What is the name of the reaction when acetamide changes into methylamine? 

(i) Hofmann bromamide reaction

(ii) Hofmann reaction

(iii) Friedel-Craft's reaction

(iv) Hinsbergh reaction

Answer:

(i) Hofmann bromamide reaction

Check Out: How to get 90+ Marks in Economics Class 12 CBSE Board?

Q12: A first-order reaction is 20% complete in 10 minutes. What is the specific rate constant for the reaction?

(i) 0.0970 min-1

(ii) 0.0009 min-1

(iii) 0.0223 min-1

(iv) 2.223 min-1

Answer:

(iii) 0.0223 min-1

Q13: Which of the following aqueous solutions should have the highest boiling point? 

(i) 1.0 M NaOH

(ii) 1.0 M Na2SO4

(iii) 1.0 M NH4NO3

(iv) 1.0 M KNO3

Answer:

(ii) 1.0 M Na2SO4

Check Out: CBSE class 12 Chemistry Marking scheme

Q14: Assertion (A): Complex reactions have the same value of order and molecularity. 

Reason (R): Molecularity is the number of molecules that participate in the reaction, while order is an experimental quantity. 

(i) Both A and R are true, but R is the correct explanation of A.

(ii) Both A and R are true, but R is not the correct explanation of A.

(iii) A is true, but R is false

(iv) A is false, and R is true

Answer:

(iv) A is false, and R is true

Q15: Which of the following statements is false in the following? 

(i) The order of a reaction may be even zero.

(ii) Molecularity of a reaction is always a whole number. 

(iii) Molecularity and order always have the same values for a reaction. 

(iv) The order of a reaction depends upon the mechanism of the reaction.

Answer:

(iii) Molecularity and order always have the same values for a reaction.

Check Out: CBSE Class 12 English Elective Syllabus 

Sample Question Papers to Boost Your CBSE Class 12th Prep

Key Takeaways

• CBSE Class 12 Chemistry can be a scoring subject if approached with the right strategies and consistent effort.
• While the list of important questions for CBSE Class 12 Chemistry provided above isn't exhaustive, it offers a valuable direction for your revision. 
• Remember, understanding the concepts, regular practice, and assessing one's preparation using mock tests and previous papers are the keys to success.