Updated On : February 13, 2024
Summary: Navigating CBSE Class 12 Chemistry exams can be daunting, but not when you're armed with potentially important CBSE Class 12 Chemistry Important Questions! Dive in for a roadmap to success.
The chemistry paper in CBSE's Class 12 exams is not just about rote learning; it tests one's conceptual clarity, analytical skills, and application of knowledge.
With a vast syllabus to cover, students often feel overwhelmed.
However, identifying potentially important questions can provide a strategic direction, instil confidence, and optimise revision time.
Let's check the CBSE Class 12 Chemistry Important Questions with answers!
Here's how to approach the important questions of chemistry CBSE Class 12 -
Instead of rote learning, focus on understanding the concepts. This will help answer both theoretical and application-based questions.
Daily practice of numerical and chemical reactions will boost confidence and improve speed.
Create mind maps for each chapter. This helps in quick revision and consolidating the main ideas.
Analyzing past papers helps in understanding the question pattern and gauging your preparation level.
Appear for multiple mock tests to practice time management and pinpoint your weaknesses.
Visit the official website to learn more about the important questions for class 12 chemistry CBSE chapter wise.
Check: CBSE Syllabus for Class 12 Chemistry
Chemistry important questions CBSE class 12 are given below -
Important questions for class 12 chemistry CBSE board 1 - Calculate the mass percentage of aspirin (C9H8O4) in acetonitrile (CH3CN) when 6.5g of C9H8O4 is dissolved in 450g of CH3CN?
Solution:
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: How to score 100 in Chemistry Class 12 CBSE
CBSE class 12 chemistry chapter wise important questions with answers 2 - Calculate the amount of benzoic acid (C6H6COOH) required to prepare 250 ml of 0.15M solution in methanol.
Solution:
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: CBSE class 12 Chemistry Reference books
Important questions Organic chemistry class 12 CBSE 3 - Define colligative properties.
Solution: Colligative properties are those properties of a solution that depend only on the number of solute particles and not on the nature of the solute.
Check: CBSE class 12 Chemistry Tips and tricks
Surface chemistry class 12 CBSE important questions 4 - 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
Solution: Allyl
CBSE Class 12 Chemistry Important Questions 5 - 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.
Solution: Stabilize the transition state and decrease the activation energy.
Check: CBSE class 12 Chemistry Marking scheme
CBSE Class 12 Chemistry Important Questions 6 - For a reaction nx+y->z, the rate of reaction 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
Solution: 3
Surface chemistry class 12 CBSE Important questions 7 - 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
Solution: increase by a factor of 4
Check: CBSE 2023 Toppers Talk
CBSE Class 12 Chemistry Important Questions 8 - Which of the following solutions has the highest osmotics pressure?
(i) 1 M NaCl
(ii) 1 M NgCI2
(iii) 1 M Urea
(iv) I M Glucose
Solution: 1 M NgCI2
CBSE Class 12 Chemistry Important Questions 9 - 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) Temperture
(ii) Nature of solute
(iii) Pressure
(iv) Nature of solvent
Solution: Pressure
Check: CBSE Class 12 Applied Mathematics
CBSE Class 12 Chemistry Important Questions 10 - In which of the following elements 5f orbitals are progressively filled?
(i) Alkaline earth metals
(ii) Actinoids
(iii) Lanthanoids
(iv) Transition elements
Solution: Actinoids
CBSE Class 12 Chemistry Important Questions 11 - 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
Solution: Hofmann bromamide reaction
Check: How to get 90+ Marks in Economics Class 12 CBSE Board?
CBSE Class 12 Chemistry Important Questions 12 - 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
Solution: 0.0223 min-1
CBSE Class 12 Chemistry Important Questions 13 - 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
Solution: 1.0 M Na2SO4
Check: CBSE class 12 Chemistry Marking scheme
CBSE Class 12 Chemistry Important Questions 14 - 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
Solution: A is false, and R is true
CBSE Class 12 Chemistry Important Questions 15 - 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.
Solution: Molecularity and order always have the same values for a reaction.
Check: CBSE Class 12 English Elective Syllabus
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 revision. Remember, understanding the concepts, regular practice, and assessing one's preparation using mock tests and previous papers are the keys to success.
Download Your Free CBSE Prep Material
Fill your details
Frequently Asked Questions
How much weightage do organic and inorganic sections carry?
Are NCERT books sufficient for CBSE Class 12 Chemistry preparation?
How can I improve my numerical-solving skills in Chemistry?
Can I skip the less important topics?
What should be my strategy a week before the exam?
February 13, 2024
Summary: Navigating CBSE Class 12 Chemistry exams can be daunting, but not when you're armed with potentially important CBSE Class 12 Chemistry Important Questions! Dive in for a roadmap to success.
The chemistry paper in CBSE's Class 12 exams is not just about rote learning; it tests one's conceptual clarity, analytical skills, and application of knowledge.
With a vast syllabus to cover, students often feel overwhelmed.
However, identifying potentially important questions can provide a strategic direction, instil confidence, and optimise revision time.
Let's check the CBSE Class 12 Chemistry Important Questions with answers!
Here's how to approach the important questions of chemistry CBSE Class 12 -
Instead of rote learning, focus on understanding the concepts. This will help answer both theoretical and application-based questions.
Daily practice of numerical and chemical reactions will boost confidence and improve speed.
Create mind maps for each chapter. This helps in quick revision and consolidating the main ideas.
Analyzing past papers helps in understanding the question pattern and gauging your preparation level.
Appear for multiple mock tests to practice time management and pinpoint your weaknesses.
Visit the official website to learn more about the important questions for class 12 chemistry CBSE chapter wise.
Check: CBSE Syllabus for Class 12 Chemistry
Chemistry important questions CBSE class 12 are given below -
Important questions for class 12 chemistry CBSE board 1 - Calculate the mass percentage of aspirin (C9H8O4) in acetonitrile (CH3CN) when 6.5g of C9H8O4 is dissolved in 450g of CH3CN?
Solution:
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: How to score 100 in Chemistry Class 12 CBSE
CBSE class 12 chemistry chapter wise important questions with answers 2 - Calculate the amount of benzoic acid (C6H6COOH) required to prepare 250 ml of 0.15M solution in methanol.
Solution:
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: CBSE class 12 Chemistry Reference books
Important questions Organic chemistry class 12 CBSE 3 - Define colligative properties.
Solution: Colligative properties are those properties of a solution that depend only on the number of solute particles and not on the nature of the solute.
Check: CBSE class 12 Chemistry Tips and tricks
Surface chemistry class 12 CBSE important questions 4 - 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
Solution: Allyl
CBSE Class 12 Chemistry Important Questions 5 - 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.
Solution: Stabilize the transition state and decrease the activation energy.
Check: CBSE class 12 Chemistry Marking scheme
CBSE Class 12 Chemistry Important Questions 6 - For a reaction nx+y->z, the rate of reaction 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
Solution: 3
Surface chemistry class 12 CBSE Important questions 7 - 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
Solution: increase by a factor of 4
Check: CBSE 2023 Toppers Talk
CBSE Class 12 Chemistry Important Questions 8 - Which of the following solutions has the highest osmotics pressure?
(i) 1 M NaCl
(ii) 1 M NgCI2
(iii) 1 M Urea
(iv) I M Glucose
Solution: 1 M NgCI2
CBSE Class 12 Chemistry Important Questions 9 - 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) Temperture
(ii) Nature of solute
(iii) Pressure
(iv) Nature of solvent
Solution: Pressure
Check: CBSE Class 12 Applied Mathematics
CBSE Class 12 Chemistry Important Questions 10 - In which of the following elements 5f orbitals are progressively filled?
(i) Alkaline earth metals
(ii) Actinoids
(iii) Lanthanoids
(iv) Transition elements
Solution: Actinoids
CBSE Class 12 Chemistry Important Questions 11 - 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
Solution: Hofmann bromamide reaction
Check: How to get 90+ Marks in Economics Class 12 CBSE Board?
CBSE Class 12 Chemistry Important Questions 12 - 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
Solution: 0.0223 min-1
CBSE Class 12 Chemistry Important Questions 13 - 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
Solution: 1.0 M Na2SO4
Check: CBSE class 12 Chemistry Marking scheme
CBSE Class 12 Chemistry Important Questions 14 - 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
Solution: A is false, and R is true
CBSE Class 12 Chemistry Important Questions 15 - 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.
Solution: Molecularity and order always have the same values for a reaction.
Check: CBSE Class 12 English Elective Syllabus
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 revision. Remember, understanding the concepts, regular practice, and assessing one's preparation using mock tests and previous papers are the keys to success.
Download Your Free CBSE Prep Material
Fill your details
Frequently Asked Questions
How much weightage do organic and inorganic sections carry?
Are NCERT books sufficient for CBSE Class 12 Chemistry preparation?
How can I improve my numerical-solving skills in Chemistry?
Can I skip the less important topics?
What should be my strategy a week before the exam?