Quick Answer
The 12th chemistry first midterm question paper typically covers the first 4 to 5 chapters of the NCERT syllabus, including Solutions, Electrochemistry, Chemical Kinetics, and basic Organic Chemistry (like Haloalkanes and Haloarenes). The exam is usually conducted for 50 marks (or 35 marks for shorter formats). To score well, focus heavily on numerical problems from Physical Chemistry and name reactions from Organic Chemistry. Scroll down to take our full mock practice test.
Syllabus Breakdown for the First Midterm
The first midterm is a crucial checkpoint in your Class 12 academic year. It tests your foundational understanding of concepts that will carry heavy weightage in the final board exams. Here are the core topics generally tested:
- Solutions: Focus on Raoult’s Law, colligative properties (elevation of boiling point, depression of freezing point), and Van’t Hoff factor.
- Electrochemistry: Nernst equation calculations, Kohlrausch’s law, and the relationship between Gibbs free energy and cell potential are guaranteed exam questions.
- Chemical Kinetics: Master the integrated rate equations for zero and first-order reactions, and understanding half-life.
- Haloalkanes and Haloarenes: Differentiate clearly between SN1 and SN2 reaction mechanisms and memorize standard name reactions (e.g., Finkelstein, Swarts, Wurtz).
Exam Pattern and Mark Distribution
While specific school boards may slightly alter the layout, the typical first midterm chemistry paper follows this structural blueprint:
| Section | Type of Questions | Weightage |
|---|---|---|
| Section A (Objective) | MCQs and Assertion-Reasoning | 1 mark each |
| Section B (Very Short) | Definitions and simple equations | 2 marks each |
| Section C (Short Answer) | Derivations and numerical problems | 3 marks each |
| Section D (Long Answer) | Multi-part conceptual questions | 5 marks each |
Class 12 Chemistry: First Midterm Mock Question Paper
Test your preparation with this highly accurate mock paper based on the official NCERT syllabus.
CHEMISTRY (THEORY)
Maximum Marks: 35 | Time Allowed: 1.5 Hours
Section A: Objective Type Questions (1 Mark Each)
- Which of the following is a colligative property?
(a) Osmotic pressure
(b) Boiling point
(c) Vapour pressure
(d) Freezing point - The unit of rate constant for a zero-order reaction is:
(a) s-1
(b) mol L-1 s-1
(c) L mol-1 s-1
(d) L2 mol-2 s-1 - In SN2 reactions, the correct order of reactivity for the following compounds is:
(a) CH3Cl > CH3CH2Cl > (CH3)2CHCl > (CH3)3CCl
(b) (CH3)3CCl > (CH3)2CHCl > CH3CH2Cl > CH3Cl
(c) CH3Cl > (CH3)2CHCl > CH3CH2Cl > (CH3)3CCl
(d) (CH3)3CCl > CH3CH2Cl > (CH3)2CHCl > CH3Cl - Assertion (A): Conductivity of an electrolyte decreases with a decrease in concentration.
Reason (R): Number of ions per unit volume decreases on dilution.
(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.
(d) A is false but R is true.
Section B: Very Short Answer Type Questions (2 Marks Each)
- State Raoult’s Law for a solution containing non-volatile solutes. How does it relate to the relative lowering of vapour pressure?
- Define Kohlrausch’s law of independent migration of ions. Write an expression for the limiting molar conductivity of acetic acid (CH3COOH).
- A first-order reaction has a rate constant k = 1.15 × 10-3 s-1. How long will 5g of this reactant take to reduce to 3g?
- Explain why alkyl halides, though polar, are immiscible with water.
Section C: Short Answer Type Questions (3 Marks Each)
- Calculate the boiling point of a solution prepared by adding 15.00g of NaCl to 250g of water.
(Given: Kb for water = 0.512 K kg mol-1, Molar mass of NaCl = 58.44 g mol-1, assume complete dissociation). - Write the Nernst equation and calculate the emf of the following cell at 298 K:
Mg(s) | Mg2+(0.001 M) || Cu2+(0.0001 M) | Cu(s)
(Given: E°Mg2+/Mg = -2.37 V, E°Cu2+/Cu = +0.34 V) - Write the chemical equations for the following name reactions:
(i) Finkelstein reaction
(ii) Swarts reaction
(iii) Wurtz reaction
Section D: Long Answer Type Questions (5 Marks Each)
- (a) Derive the integrated rate equation for a first-order reaction. (3 marks)
(b) The half-life for radioactive 14C is 5730 years. An archaeological artifact containing wood had only 80% of the 14C found in a living tree. Estimate the age of the sample. (2 marks) - (a) Explain the mechanism of an SN1 reaction using the hydrolysis of 2-bromo-2-methylpropane as an example. Discuss the stereochemistry involved. (3 marks)
(b) Out of chlorobenzene and cyclohexyl chloride, which one is more reactive towards nucleophilic substitution reactions and why? (2 marks)
How to Prepare: Expert Study Tips
1. Practice NCERT Intext and Exercise Questions
Teachers frequently lift midterm questions directly from the NCERT textbook. Prioritize solving the “Intext” questions for Physical Chemistry chapters. You can find official curriculum guidelines at the Official NCERT Website.
2. Maintain a Formula and Reaction Log
Create a dedicated cheat sheet for the Nernst Equation, Arrhenius Equation, and all Organic Chemistry name reactions. Writing them down daily improves retention significantly. For more tips on organizing your study schedule, explore our Class 12 Board Exam Study Guide.
TL;DR Summary
The 12th chemistry first midterm question paper is your first real test of board-level preparation. It usually covers Solutions, Electrochemistry, Chemical Kinetics, and introductory Organic Chemistry. To secure top marks, use our included mock paper to practice NCERT numericals, memorize the conditions for SN1 vs SN2 reactions, and ensure you are comfortable with assertion-reasoning style questions. Do not ignore your textbook exercises—they are the most reliable source of exam questions!
