12TH CBSE Electrochemistry 25 MCQS ONLINE Test WITH ANSWERS

Electrochemistry - 25 MCQ Test

1. In a Leclanche dry cell, the cathode is:

Zn container
MnO₂
Graphite rod
NH₄Cl

2. In a fuel cell, energy conversion is:

Chemical → Electrical
Electrical → Chemical
Combustion Energy → Electrical
Light → Electrical

3. Purpose of a salt bridge in an electrochemical cell?

Oxidizing agent
Reducing agent
Complete the circuit
Catalyst

4. For a spontaneous reaction:

ΔG positive, E° positive
ΔG negative, E° positive
ΔG positive, E° negative
Both negative

5. Zinc is coated over iron because:

E°Zn = E°Fe
E°Zn < E°Fe
E°Zn > E°Fe
None

6. One mole of Zn from ZnSO₄ requires:

1F
2F
3F
4F

7. In lead storage battery, cathode reaction produces:

Pb
PbSO₄
PbO₂
H₂

8. Copper corrodes in industrial smog forming:

Copper oxide
Copper nitrate
Basic copper carbonate & sulphate
Copper sulphide

9. EMF is the difference between electrode potentials when:

Current flows
No current flows
Cell shorted
Battery charged

10. Negative terminal of a dry cell is:

Carbon rod
Graphite rod
Zinc container
NH₄Cl

11. Rusting of iron is an example of:

Reduction
Oxidation
Neutralization
Sublimation

12. Water decomposes into H₂ and O₂ by:

Distillation
Electrolysis
Filtration
Sublimation

13. 1 Faraday equals:

96500 C
95000 C
10000 C
96.5 C

14. Anode in a galvanic cell is:

Positive
Neutral
Negative
Cathode

15. Cathode in an electrolytic cell acts as:

Oxidizing agent
Reducing agent
Electrolyte
Salt bridge

16. Number of Faradays in lead accumulator reaction:

1
0.5
2
4

17. 6.24 × 10¹⁹ electrons equal:

10 C
1 C
96500 C
0.1 C

18. Corrosion is accelerated by:

Moisture
Temperature
Pressure
All of these

19. Splitting a compound using electricity is:

Distillation
Electrolysis
Crystallization
Oxidation

20. Capacity of a cell is measured in:

Watt
Ampere
Ampere-hour
Volt

21. Gold is resistant to corrosion because it is:

Highly reactive
Least reactive
Radioactive
Magnetic

22. Primary battery is:

Rechargeable
Cannot be recharged
Solar powered
Fuel cell

23. Aluminium from bauxite is obtained by:

Distillation
Filtration
Electrolysis
Sublimation

24. A voltaic cell converts:

Electrical → Chemical
Chemical → Electrical
Mechanical → Electrical
Light → Electrical

25. Electrons flow in a galvanic cell from:

Cathode to Anode
Anode to Cathode
Electrolyte to Salt Bridge
Salt Bridge to Electrolyte