Question

Assertion (A): In the electrolysis of acidified water, the volume of hydrogen liberated is twice the volume of oxygen formed.

Reason (R): Water has hydrogen and oxygen in the ratio of 1 : 2 by volume.

Options

• (A) is true but (R) is false.

• (A) is false but (R) is true.

• Both (A) and (R) are true, and (R) is the correct explanation of (A).

• Both (A) and (R) are true, but (R) is not the correct explanation of (A).

Answer 1

(A) is true but (R) is false.

Explanation:

Electrolysis of water is 2 H₂ + O₂ (so 2 volumes H₂ : 1 volume O₂) because \[\ce{2 H2O → 2 H2 + O2}\] (half‑reactions show this). Water (H₂O) contains hydrogen and oxygen in a volume ratio of 2 : 1, not 1 : 2.