Important Questions Class 12 Chemistry Chapter 2, PDF Download

If you are preparing for your board exams, revising Important Questions Class 12 Chemistry Chapter 2 is very important for scoring well in numerical and concept-based questions. Chapter 2 focuses on electrochemical cells, Nernst equation, conductance, molar conductivity, and electrolysis, which are frequently asked in exams. 

Practising Electrochemistry class 12 important questions helps students strengthen problem-solving skills, understand formulas clearly, and improve accuracy in numerical calculations. Regular revision of key derivations and concepts from this chapter can significantly boost confidence and exam performance.

Important Questions Class 12 Chemistry Chapter 2

Below are the Important Questions Class 12 Chemistry Chapter 2 designed to help students revise key concepts effectively before exams. These questions cover important topics such as electrochemical cells, Nernst equation, conductance, molar conductivity, electrolysis, and numerical problem-solving. 

Practising Electrochemistry Class 12 Chemistry Important Question sets helps improve conceptual clarity and accuracy in calculations.

Students should also solve Class 12 Chemistry Electrochemistry MCQ regularly to strengthen objective question practice and boost confidence for board examinations. 

1. Charge of one mole of electrons is:

(1) 1.6021 × 10–19 C 

(2) 96500 C 

(3) 6.022 × 1023 C 

(4) 1 C

2. (i) The standard electrode potential for Daniel cell is 1.1 V. Calculate the standard Gibbs Energy change for the reaction: 

Zn(s) + Cu2+(aq) → Zn2+ (aq) + Cu(s).                                               

(ii) Explain the working of H2 – O2 fuel cell.                                                     

3. Λ°m for NaCl, HCl and NaAc are 126.4, 425.9 and 91.0 S cm2 mol–1 respectively. Calculate Λ°m for HAc.

4. An electrochemical cell can behave like an electrolytic cell when ________.

(1) Ecell = 0 (2) Ecell > Eext

(3) Eext > Ecell (4) Ecell = Eext

5. (i) The conductivity of an electrolytic solution decreases as dilution increases. Why ? 

(ii) Explain the variation of molar conductivity with dilution in the case of strong and weak electrolytes.

(iii) State Kohlrausch’s law. [March 2025]

6. You are supplied with the following substances: Copper rod, zinc rod, salt bridge, two glass beakers, a piece of wire, 1 M CuSO4 solution, 1 M ZnSO4 solution.

   a) Represent the cell made using the above materials.

   b) i)   Write the Nernst equation for the above cell. 

ii)   Calculate the standard emf of the cell if E°

(Zn2+|Zn) = – 0.76 V and E° (Cu2+|Cu) = + 0.34V.

7. Which of the following is a secondary cell?

(1) Dry cell

(2) Leclanche cell

(3) Mercury cell

(4) None of these

8. Kohlrausch’s law helps to determine the degree of dissociation of weak electrolyte at a given concentration.

i) State Kohlrausch’s law.

ii) The molar conductivity (Λm) of 0.001 M acetic acid is 4.95 × 10–5 S cm2 mol–1. Calculate the degree of dissociation (α) at this concentration if the limiting molar conductivity (λ°m) for H+ is 340 × 10–5 S cm2 mol–1 and for CH3COO is 50.5 × 10–5 Scm2 mol–1.       [SAY 2017]

9. A solution of CuSO4, is electrolysed for 20 minutes with a current of 1.5 amperes. What is the mass of copper deposited at cathode? (Atomic mass of copper = 63)

10. Predict the products of electrolysis of the following substances at anode and cathode using suitable chemical equations: 

(a) Aqueous NaCl (b) H2SO4 solution 

Last Minute Preparation Tips for Class 12 Chemistry Chapter 2 Electrochemistry

If your exam is near, focus on a quick revision of formulas and key concepts from Electrochemistry. This chapter is numerical-based, so clarity and practice are very important.

• First, revise important formulas like the Nernst equation, relation between Gibbs free energy and EMF, and formulas for conductance and molar conductivity. Make sure you understand how to apply these formulas in numerical problems.

• Next, clearly revise electrochemical cells, standard electrode potentials, and the working of galvanic and electrolytic cells. Practice writing cell notation correctly. Questions based on calculating EMF and predicting spontaneity are very common.

• Also, revise Kohlrausch’s Law and its applications carefully, as it is frequently asked in board exams. Go through solved examples from NCERT because many questions are directly based on them.

• Do not try to start new topics at the last moment. Instead, revise important derivations, units, and definitions. Stay calm, manage your time well in the exam, and show proper steps while solving numericals to score full marks.