In which of the following reactions of $\mathrm{H}_2 \mathrm{O}_2$ acts as an oxidising agent (either in acidic, alkaline or neutral medium)? (i) $2 \mathrm{Fe}^{2+}+\mathrm{H}_2 \mathrm{O}_2{ }^{\prime} \rightarrow$ (ii) $2 \mathrm{MnO}_4^{-}+6 \mathrm{H}^{+}+5 \mathrm{H}_2 \mathrm{O}_2 \rightarrow$ (iii) $\mathrm{I}_2+\mathrm{H}_2 \mathrm{O}_2+2 \mathrm{OH}^{-} \rightarrow$ (iv) $\mathrm{Mn}^{2+}+\mathrm{H}_2 \mathrm{O}_2 \rightarrow$

• A

  (ii),(iii)
• Correct answer
  B

  (i), (iv)
• C

  (i), (iii)
• D

  (ii), (iv)

Solution

Let us complete the reactions: In reactions, $(i)$ and $(i v) \mathrm{H}_2 \mathrm{O}_2$, acts as oxidising agent and itself gets reduced to $\mathrm{H}_2 \mathrm{O}$,

Hence, the correct answer is option: 'B'.