JEE Main Electrochemistry Previous Year Questions With Solutions

1. In a hydrogen-oxygen fuel cell, combustion of hydrogen occurs to

(a) generate heat

(b) create a potential difference between the two electrodes

(c) produce high purity water

(d) remove adsorbed oxygen from the electrode surface.

Solution:

The correct option for the given question is (b).

2. Conductivity (unit Siemen’s S) is directly proportional to the area of the vessel and the concentration of the solution in it and is inversely proportional to the length of the vessel then the unit of the constant of proportionality is

(a) Sm mol^-1

(b) Sm² mol^-1

(c) S^-2m² mol¹

(d) S²m² mol¹

Solution:

The correct option for the given question is (b).

3. Galvanization is applying a coating of

(a) Pb

(b) Cr

(c) Cu

(d) Zn

Solution:

The correct option for the given question is (d).

4. Identify the correct statement.

(a) Corrosion of iron can be minimized by forming contact with another metal with a higher reduction potential.

(b) Iron corrodes in oxygen-free water.

(c) Corrosion of iron can be minimized by forming an impermeable barrier at its surface.

(d) Iron corrodes more rapidly in saltwater because its electrochemical potential is higher.

Solution:

The correct option for the given question is (c).

5. A solution of Ni(NO₃ )₂ is electrolyzed between platinum electrodes using 0.1 Faraday electricity. How many moles of Ni will be deposited at the cathode?

(a) 0.10

(b) 0.15

(c) 0.20

(d) 0.05

Solution:

The correct option for the given question is (d).

6. EMF of a cell in terms of reduction potential of its left and right electrodes is

(a) E = E_left – E_right

(b) E = E_left + E_right

(c) E = E_right – E_left

(d) E = –(E_right + E_left)

Solution:

The correct option for the given question is (c).

7. For a cell reaction involving a two-electron change, the standard e.m.f. of the cell is found to be 0.295 V at 25°C. The equilibrium constant of the reaction at 25°C will be

(a) 1 × 10^–10

(b) 29.5 × 10^–2

(c) 10

(d) 1 × 10¹⁰

Solution:

The correct option for the given question is (d).

8. If φ denotes reduction potential, then which is true?

(a) E°cell = φ_right – φ_left

(b) E°cell = φ_left + φ_right

(c) E°cell = φ_left – φ_right

(d) E°cell = –(φ_left +φ_right)

Solution:

The correct option for the given question is (a).

9. The anodic half-cell of lead-acid battery is recharged using electricity of 0.05 Faraday. The amount of PbSO₄ electrolyzed in g during the process is [Molar mass of PbSO₄ = 30₃ g mol^–1]

(a) 15.2

(b) 11.4

(c) 7.6

(d) 22.8

Solution:

The correct option for the given question is (c).

10. Calculate the standard cell potential (in V) of the cell in which the following reaction takes place. Fe²⁺ _(aq) + Ag⁺ _(aq) → Fe³⁺ _(aq) + Ag_(s)

Given that E°_{Ag⁺ /Ag} = x V; E°_{Fe²⁺ /Fe} = y V; E°_{Fe³⁺ /Fe} = z V

(a) x – z

(b) x – y

(c) x + 2y – 3z

(d) x + y – z

Solution:

The correct option for the given question is (c).

11. The standard Gibbs energy for the given cell reaction in kJ mol^–1 at 298 K is

Zn_(s) + Cu²⁺ _(aq) → Zn²⁺_(aq) + Cu_(s), E ° = 2 V at 298 K (Faraday’s constant, F = 96000 C mol^–1) (a) –192

(b) 192

(c) –384

(d) 384

Solution:

The correct option for the given question is (c).

12. Consider the statements S1 and S2:

S1: Conductivity always increases with a decrease in the concentration of electrolytes.

S2: Molar conductivity always increases with a decrease in the concentration of electrolytes. The correct option among the following is

(a) both S1 and S2 are wrong

(b) both S1 and S2 are correct

(c) S1 is wrong and S2 is correct

(d) S1 is correct and S2 is wrong.

Solution:

The correct option for the given question is (c).

13. If the standard electrode potential for a cell is 2 V at 300 K, the equilibrium constant (K) for the reaction,

Zn(s) + Cu₂ + (aq) Zn₂ + (aq) + Cu(s)

at 300 K is approximately (R = 8 J K^–1 mol^–1, F = 96500 C mol^–1)

(a) e^–80

(b) e ¹⁶⁰

(c) e ^–160

(d) e ³²⁰

Solution:

The correct option for the given question is (b).

14. When during electrolysis of a solution of AgN0₃ 9650 coulombs of charge pass through the electroplating bath, the mass of silver deposited on the cathode will be

(a) 10.8 g

(b) 21.6 g

(c) 108 g

(d) 1.08 g

Solution:

The correct option for the given question is (a).

15. The correct order of E⁰_M2+/M values with negative sign for the four successive elements Cr, Mn, Fe and Co is

(a) Mn > Cr > Fe > Co

(b) Cr > Fe > Mn> Co

(c) Fe > Mn > Cr > Co

(d) Cr > Mn > Fe > Co

Solution:

The correct option for the given question is (a).

Also read: JEE Main Exam Mode

FAQs

Q. What are the subjects shrouded in the JEE Mains, Redox Reactions and Electrochemistry section?

Ans: Numerous significant themes are canvassed in the Redox Reactions and Electrochemistry, these points are: –

• Electronic Concepts of Oxidation and Reduction
• Redox Reactions
• Oxidation Number
• Rules for Assigning oxidation number
• Adjusting of Redox responses.
• Electrolytic and Metallic conduction
• Conductance in electrolytic arrangements
• Molar conductivities with their Variation with focus Kohlrausch’s regulation and its application
• Electrochemical cells, Electrolytic and Galvanic cells
• Various sorts of cathodes
• Terminal possibilities alongside standard anode potential, half cell and cell responses
• emf of a Galvanic cell and its estimation – Nernst condition and its applications
• The connection between cell potential and Gibbs’ energy change – Dry cell and lead collector, Fuel cells.

Are earlier year questions enough for JEE mains science?

Chemistry earlier years papers gives a thought of around 80 % of what is generally anticipated to come next jee man. Still, science in jee principle is simple when contrasted with different subjects, so read great reference books and score well.