NCERT Class 12 Chemistry Chapter 2 Electrochemistry MCQs & PYQ

1.

The correct cell to represent the following reaction is: Zn + 2Ag+ → Zn2+ + 2Ag

(a) 2Ag | Ag+ || Zn| Zn2+ (b) Ag+ | Ag || Zn2+ | Zn

(c) Ag | Ag+ | Zn || Zn2+ (d) Zn | Zn2+ || Ag+ | Ag

2.

Consider the following standard electrode potential values: 

What is the cell potential for the redox reaction? 

(a) −2.28 𝑉 (b) −0.74 𝑉 (c) +0.74 𝑉 (d) +2.28 𝑉 

3.

A voltaic cell is made by connecting two half cells represented by half equations below:

Which statement is correct about this voltaic cell?

(a) 𝐹𝑒2+ is oxidized and the voltage of the cell is -0.91V

(b) 𝑆𝑛 is oxidized and the voltage of the cell is 0.91 V

(c) 𝐹𝑒2+ is oxidized and the voltage of the cell is 0.91 V

(d) 𝑆𝑛 is oxidized and the voltage of the cell is 0.63 V

4.

∆G and for a spontaneous reaction will be:

(a) positive, negative (b) negative, negative

(c) negative, positive (d) positive, positive

5.

Ag+ (aq) + e– →Ag (s) E° = + 0.80 V

Fe2+ (aq) + 2e– →Fe (s) E° = – 0.44 V

Find the for: Fe (s) + 2Ag+ (aq) → Fe2+ (aq) + 2Ag (s)

(a) 1.6 V (b) 1.16 V (c) 2.04 V (d) 1.24 V

1.

(i) What should be the signs (positive /negative) for and Δ 𝐺° for a spontaneous redox reaction occurring under standard conditions?

(ii) State Faraday’s first law of electrolysis.

(CBSE 2023, 2M)

2.

Calculate the emf of the following cell at 25˚C :

Al (s) |Al3+ (0·001 M) || (0·1) Ni2+ |Ni (s)

Given :       

[ log 2 = 0·3010, log 3 = 0·4771 ]

(CBSE 2019, 3M)

3.

(a) Calculate the emf of the following cell at 25°C:

Zn (s) | Zn2+ (0·1 M) || H+ (0·01 M) | H2 (g) (1 bar), Pt (s)

[Given :]

(b) State Kohlrausch law of independent migration of ions. Why does the conductivity of a solution decrease with dilution?

(CBSE 2023, 5M)

4.

Calculate the EMF of the following cell at 298 K:

𝐹𝑒(𝑠) | 𝐹𝑒2+(0.01𝑀) || 𝐻|𝐻2(𝑔) (1 𝑏𝑎𝑟), 𝑃𝑡(𝑠)

Given = 0.44 𝑉.

(CBSE 2023, 2M)

5.

Write the Nernst equation for the following cell reaction :

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

How will the Ecell be affected when concentration of

(i) Cu2+ ions is increased and

(ii) Zn2+ ions is increased?

(CBSE 2022, 2M)

Chapter Name

Sub Topics of Chapter 2: Electrochemistry

Electrochemistry

2.1 Introduction

2.2 Electrochemical Cells

2.3 Galvanic Cells

2.4 Nernst Equation

2.5 Conductance of Electrolytic Solutions

2.6 Electrolytic Cells and Electrolysis

2.7 Batteries

2.8 Fuel Cells

2.9 Corrosion