During electrolysis of water, hydrogen is liberated at: MCQ with Answer and Explanation

During electrolysis of water, hydrogen is liberated at:
A. Both electrodes
B. Cathode
C. Salt bridge
D. Anode
Answer: Option B
Solution (By JKSSB Mock Tests)
Cathode (negative electrode): 2H₂O + 2e⁻ → H₂ + 2OH⁻ (or 2H⁺ + 2e⁻ → H₂). Hydrogen gas is collected at the cathode. At the anode, oxygen is produced: 2H₂O → O₂ + 4H⁺ + 4e⁻. The volume of H₂ is double that of O₂.

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