Physics Wallah

CBSE Class 12 Chemistry 30 Most Important Questions

CBSE Class 12 Chemistry 30 Most Important Questions is a focused revision set for students preparing for the board exam conducted by the Central Board of Secondary Education. These questions cover high-weightage chapters such as Electrochemistry, Organic Chemistry, Coordination Compounds, Chemical Kinetics, and Solutions. Practicing them helps improve concepts, strengthen numerical skills, and boost confidence for the final exam.
NCERT Solutions
Notes
PYQs
Sample Paper
CBSE Class 12 Chemistry 30 Most Important Questions

CBSE Class 12 Chemistry 30 Most Important Questions is a simple and focused revision resource for students preparing for the Central Board of Secondary Education Class 12 Chemistry exam on 28 February 2026. It includes important questions from high-weightage chapters like Electrochemistry, Organic Chemistry, Coordination Compounds, and Chemical Kinetics.

These questions are selected based on previous year trends and important concepts frequently asked in board exams. Practicing them helps students strengthen conceptual clarity, improve speed and accuracy in numericals, and revise key reactions, formulas, and derivations effectively. This targeted preparation also reduces last-minute stress and boosts overall confidence to score high marks in the final board examination.

CBSE Class 12 Chemistry 30 Most Important Questions

Below is the CBSE Class 12 Chemistry 30 Most Important Questions, specially selected to help students prepare effectively for the board exam scheduled on 28 February 2026. These questions cover high-weightage chapters such as Electrochemistry, Organic Chemistry, Coordination Compounds, Chemical Kinetics, Solutions, and p-Block Elements. Practicing these important questions will improve conceptual understanding, strengthen numerical problem-solving skills, and boost confidence for scoring high marks in the final exam.

Electrochemistry

  1. Define electrochemical cell. How is EMF of a cell measured?

  2. State and explain the Nernst equation.

  3. Calculate the EMF of a cell using standard electrode potentials.

  4. Define conductivity and molar conductivity.

  5. Explain Kohlrausch’s Law of independent migration of ions.

  6. What is electrolysis? State Faraday’s laws of electrolysis.

Chemical Kinetics

  1. Define rate of reaction and rate constant.

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

  3. What is half-life? Derive the expression for half-life of a first-order reaction.

  4. Explain the effect of temperature on reaction rate (Arrhenius equation).

Coordination Compounds

  1. Define coordination number and oxidation state.

  2. Explain types of isomerism in coordination compounds.

  3. Write IUPAC names of coordination compounds.

  4. What is Crystal Field Theory?

  5. Explain the difference between strong field and weak field ligands.

Organic Chemistry (Aldehydes, Ketones, Carboxylic Acids)

  1. Write reactions of aldehydes and ketones with nucleophiles.

  2. Explain Aldol condensation.

  3. What is Cannizzaro reaction?

  4. Distinguish between aldehydes and ketones (chemical tests).

  5. Describe preparation and properties of carboxylic acids.

Haloalkanes & Haloarenes

  1. Explain SN1 and SN2 reactions.

  2. Why are aryl halides less reactive than alkyl halides?

Alcohols, Phenols & Ethers

  1. Explain acidic nature of phenol.

  2. Describe Williamson ether synthesis.

Solutions

  1. Define colligative properties.

  2. Explain abnormal molar mass using van’t Hoff factor.

d- and f-Block Elements

  1. Explain properties of transition elements.

  2. Why do transition metals show variable oxidation states?

Biomolecules / Polymers

  1. What are proteins? Explain peptide bond.

  2. Define polymers. Differentiate between addition and condensation polymers.

Chemistry Exam Preparation Strategy 

Below is the Chemistry Exam Preparation Strategy to help students prepare effectively for the board exam.

  • Revise high-weightage chapters like Electrochemistry, Organic Chemistry, Coordination Compounds, Chemical Kinetics, and Solutions.

  • Make short notes of important formulas, reactions, definitions, and key concepts.

  • Practice previous year questions (PYQs) and sample papers regularly.

  • Focus on numerical problems and learn all important formulas.

  • Revise named reactions, mechanisms, and key derivations.

  • Practice assertion–reason and case-based questions.

  • Manage time properly while solving mock tests.

  • Solve at least one full-length sample paper before the exam.

  • Do quick revision in the last few days before the exam.

  • Stay calm, confident, and avoid last-minute stress.

CBSE Class 12 Chemistry 30 Most Important Questions FAQs

What is Henry's Law and how does it relate to gas solubility?

Henry's Law states that the partial pressure of a gas over a liquid is directly proportional to its mole fraction (solubility) in that liquid. A higher Henry's Law constant (KH) indicates lower gas solubility.

How do Ideal and Non-Ideal Solutions differ in terms of Raoult's Law and intermolecular forces?

Ideal solutions obey Raoult's Law with A-B intermolecular forces similar to A-A and B-B. Non-ideal solutions show deviations: positive deviation has weaker A-B forces and higher vapor pressure, while negative deviation has stronger A-B forces and lower vapor pressure.

Explain the Nernst equation and its practical application.

The Nernst equation calculates cell potential (E_cell) under non-standard conditions using E_cell = E°_cell - (0.0591 / n) * log₁₀([Products] / [Reactants]) at 25°C. It shows how E_cell decreases as a reaction proceeds and concentrations change.

What experimental evidence supports the presence of an aldehyde group and a primary alcohol group in glucose?

Glucose reacts with mild oxidizing agent bromine water to form gluconic acid, indicating an aldehyde group. It reacts with strong oxidizing agent nitric acid to form saccharic acid, confirming both an aldehyde and a primary alcohol group.
Free Learning Resources
Know about Physics Wallah
Physics Wallah is an Indian edtech platform that provides accessible & comprehensive learning experiences to students from Class 6th to postgraduate level. We also provide extensive NCERT solutions, sample paper, NEET, JEE Mains, BITSAT previous year papers & more such resources to students. Physics Wallah also caters to over 3.5 million registered students and over 78 lakh+ Youtube subscribers with 4.8 rating on its app.
We Stand Out because
We provide students with intensive courses with India’s qualified & experienced faculties & mentors. PW strives to make the learning experience comprehensive and accessible for students of all sections of society. We believe in empowering every single student who couldn't dream of a good career in engineering and medical field earlier.
Our Key Focus Areas
Physics Wallah's main focus is to make the learning experience as economical as possible for all students. With our affordable courses like Lakshya, Udaan and Arjuna and many others, we have been able to provide a platform for lakhs of aspirants. From providing Chemistry, Maths, Physics formula to giving e-books of eminent authors like RD Sharma, RS Aggarwal and Lakhmir Singh, PW focuses on every single student's need for preparation.
What Makes Us Different
Physics Wallah strives to develop a comprehensive pedagogical structure for students, where they get a state-of-the-art learning experience with study material and resources. Apart from catering students preparing for JEE Mains and NEET, PW also provides study material for each state board like Uttar Pradesh, Bihar, and others
Privacy Policy
Terms of use
Copyright © 2026 Physicswallah Limited All rights reserved.