Electrochemistry – Class 12 Chemistry NEET MCQs

Electrochemistry – Class 12 Chemistry NEET Practice MCQs

1. In a galvanic cell, chemical energy is converted into:
   (a) Electrical energy
   (b) Mechanical energy
   (c) Heat energy
   (d) Light energy


2. The electrode at which oxidation takes place is called:
   (a) Cathode
   (b) Anode
   (c) Salt bridge
   (d) Membrane


3. In Daniell cell, zinc acts as:
   (a) Cathode
   (b) Anode
   (c) Both
   (d) None


4. The EMF of a cell is given by:
   (a) E = E°cell + (RT/nF) ln Q
   (b) E = E°cell - (RT/nF) ln Q
   (c) E = nFE°
   (d) E = -nFE°


5. In the Nernst equation, the term RT/nF log(1/[ion]) represents:
   (a) Concentration potential
   (b) Diffusion potential
   (c) Osmotic potential
   (d) None


6. For the cell reaction Zn + Cu²⁺ → Zn²⁺ + Cu, E°cell is:
   (a) 1.10 V
   (b) 0.76 V
   (c) 0.34 V
   (d) 2.20 V


7. If E°(Ag⁺/Ag) = +0.80 V and E°(Cu²⁺/Cu) = +0.34 V, then E°cell for Cu–Ag cell is:
   (a) 0.46 V
   (b) 1.14 V
   (c) 0.50 V
   (d) 0.12 V


8. In an electrolytic cell, the direction of electron flow is:
   (a) Cathode → Anode
   (b) Anode → Cathode
   (c) Random
   (d) Both directions


9. The unit of cell constant is:
   (a) m⁻¹
   (b) cm⁻¹
   (c) ohm⁻¹ cm⁻¹
   (d) ohm⁻¹


10. Which of the following has the highest conductivity?
    (a) 0.1 M NaCl
    (b) 0.01 M NaCl
    (c) 1 M NaCl
    (d) 0.001 M NaCl


11. Faraday’s first law states that mass deposited is proportional to:
    (a) Current only
    (b) Time only
    (c) Charge passed
    (d) Resistance


12. 1 Faraday corresponds to:
    (a) 96500 C
    (b) 1 C
    (c) 1 J
    (d) 9650 C


13. In electrolysis of CuSO₄ using Pt electrodes, what is liberated at cathode?
    (a) O₂
    (b) Cu
    (c) H₂
    (d) SO₂


14. When two half-cells are connected, the electrons flow from:
    (a) Lower E° to higher E°
    (b) Higher E° to lower E°
    (c) Anode to cathode
    (d) Both (a) and (c)


15. The relationship between specific conductance (κ), cell constant (l/A) and resistance (R) is:
    (a) κ = R × l/A
    (b) κ = 1/R × l/A
    (c) κ = R/(l/A)
    (d) None


16. Electrochemical equivalent (Z) is given by:
    (a) Z = E/F
    (b) Z = W/Q
    (c) Z = F/E
    (d) Z = Q/W


17. Conductivity of a solution decreases with:
    (a) Increase in temperature
    (b) Increase in dilution
    (c) Increase in concentration
    (d) None


18. Kohlrausch’s law is applicable to:
    (a) Strong electrolytes only
    (b) Weak electrolytes only
    (c) Both strong and weak electrolytes
    (d) Non-electrolytes


19. The standard reduction potential of Zn²⁺/Zn is -0.76 V. It means:
    (a) Zn²⁺ is easily reduced
    (b) Zn is easily oxidized
    (c) Both
    (d) None


20. The equivalent conductance of an electrolyte at infinite dilution is denoted by:
    (a) Λ
    (b) Λm
    (c) Λ°m
    (d) κ

Answers and Explanations

1. (a) Chemical → Electrical energy conversion.
2. (b) Oxidation occurs at anode.
3. (b) Zinc acts as anode (oxidation).
4. (b) Nernst equation: E = E°cell - (RT/nF) ln Q.
5. (a) Concentration potential term.
6. (a) 1.10 V for Zn–Cu cell.
7. (a) 0.46 V = 0.80 - 0.34.
8. (b) From anode → cathode (electrons flow).
9. (b) cm⁻¹.
10. (c) 1 M NaCl – highest ion concentration.
11. (c) Mass ∝ charge (Q = It).
12. (a) 96500 coulombs per mole of electrons.
13. (b) Copper is deposited at cathode.
14. (d) Both (a) and (c) are correct.
15. (b) κ = (l/A)/R.
16. (b) Z = W/Q (mass per unit charge).
17. (b) Conductivity decreases on dilution.
18. (c) Applicable to both types of electrolytes.
19. (b) Zn easily oxidizes (negative potential).
20. (c) Λ°m – molar conductance at infinite dilution.