Question

Which acts as reducing agent as well as oxidising agent?

• A. $O_3$
• B. ${ClO}_4^{-}$
• C. $F_2$
• D. ${MnO}_4^{-}$

Answer 1

Answer: (A)

$O_3$

Among the following compounds, Ozone (O₃) acts as a reducing as well as oxidising agent and itself decomposes to liberate nascent oxygen atoms.

Examples:

• Oxidation-

Ozone oxidizes lead sulphide forming lead sulphate.

PbS + 4O₃ → PbSO₄ + 4O₂

Ozone oxidizes potassium iodide forming iodine.

2KI + O₃ + H₂O → 2KOH + I₂ + H₂O

• Reduction-

Ozone reduces hydrogen peroxide forming water.

H₂O₂ + O₃ → H₂O + 2O₂

Ozone reduces barium peroxide forming barium oxide.

BaO₂ + O₃ → BaO + 2O₂

Hence, option A is correct.