Question

During electrolysis of water, and are liberated at anode and cathode respectively.

• A. hydrogen
• B. oxygen
• C. nitrogen
• D. water vapour

Answer 1

Answer: (A), (B)

oxygen

During electrolysis of water, electricity is passed through acidified or salt water. Water undergoes decomposition and the process liberates hydrogen gas at the cathode and oxygen gas at the anode. The schematic diagram is given below:

The reaction occurs as follows:

${\text{2H}}_2\text{O (l)}\to 2{\text{H}}_2\text{(g)}+{\text{O}}_2\text{(g)}$