On electrolysis of very dilute aqueous solution of NaCl using platinum electrodes :
Show Hint
- H2 gas is evolved at anode.
- Na is produced at anode.
- O2 gas is evolved at anode.
- H2 gas is evolved at cathode.
The Correct Option is C
Solution and Explanation
Anode (oxidation): 2H2O → O2 + 4H+ + 4e– — so O2 is evolved (Cl2 would need concentrated brine).
Answer: (C) O2 gas is evolved at anode.
Note: at the cathode H2O is reduced to H2, so option (D) is also a true statement; option (C) is the one that specifically reflects the 'very dilute' condition being tested.
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