Question

In basic medium, H₂O₂ exhibits which of the following reactions ? (A) Mn²⁺ → Mn⁴⁺ (B) I₂ → I⁻ (C) PbS → PbSO₄ Choose the most appropriate answer from the options given below :

• A. (A) only
• B. (B) only
• C. (A), (B) only
• D. (A), (C) only

Hint:

{Hydrogen Peroxide Reactivity:} $H_2O_2$ is a "dual-agent." In basic medium, it is a very strong {reducing agent} for halogens (like $I_2 \rightarrow I^-$) and a powerful {oxidizing agent} for metal ions in lower oxidation states (like $Mn^{2+} \rightarrow Mn^{4+}$).

Answer 1

The Correct Option is C

Step 1: In basic medium, \(H_2O_2\) can act as both an oxidizing and a reducing agent.
Step 2: Reaction (A): \(Mn^{2+} + H_2O_2 \rightarrow MnO_2 (Mn^{4+})\). This is an oxidation of \(Mn^{2+}\) by \(H_2O_2\) in basic medium. (Correct).
Step 3: Reaction (B): \(I_2 + H_2O_2 + 2OH^- \rightarrow 2I^- + 2H_2O + O_2\). This is the reduction of iodine in basic medium. (Correct).
Step 4: Reaction (C): \(PbS + 4H_2O_2 \rightarrow PbSO_4 + 4H_2O\). This oxidation typically occurs in acidic or neutral medium.