Answer:
Oxygen is oxidized and hydrogen is reduced.
Explanation:
Let's consider the redox reaction during the electrolysis of water in an electrolytic cell.
2 H₂O ⇒ 2 H₂ + O₂
The corresponding half-reactions are:
2 e⁻ + 2 H₂O ⇒ H₂ + 2 OH⁻
2 H₂O ⇒ O₂ + 4 H⁺ + 4 e⁻
Oxygen is oxidized since its oxidation number increases from -2 to 0.
Hydrogen is reduced since its oxidation number decreases from +1 to 0.
