Q.Write two oxidation and two reduction reactions of Hydrogen peroxide.

$\text{H}_2\text{O}_2$ shows dual redox behaviour — it can act as an oxidising agent (getting reduced, O going from $-1$ to $-2$) or as a reducing agent (getting oxidised, O going from $-1$ to $0$, releasing $\text{O}_2$).

In $\text{H}_2\text{O}_2$, oxygen is in the $-1$ oxidation state, which is intermediate between $-2$ (in $\text{H}_2\text{O}$) and $0$ (in $\text{O}_2$). This lets it act as either an oxidising or reducing agent depending on the other species involved.

As an oxidising agent (H₂O₂ itself is reduced; O: $-1 \rightarrow -2$):

1. In acidic medium, it oxidises $\text{Fe}^{2+}$ to $\text{Fe}^{3+}$:

   $2\text{Fe}^{2+}(aq) + 2\text{H}^+(aq) + \text{H}_2\text{O}_2(aq) \rightarrow 2\text{Fe}^{3+}(aq) + 2\text{H}_2\text{O}(l)$

2. It oxidises lead sulphide (used to restore blackened lead-based old paintings):

   $\text{PbS}(s) + 4\text{H}_2\text{O}_2(aq) \rightarrow \text{PbSO}_4(s) + 4\text{H}_2\text{O}(l)$

As a reducing agent (H₂O₂ itself is oxidised, releasing O₂; O: $-1 \rightarrow 0$):

3. It reduces acidified potassium permanganate: …