Q5 / 150 · MHT CET 2021 (20 Sep Shift 1) · Chemistry
What is the value of ' $x$ ' in order to balance the following redox reaction by ion electron method?
$$
\mathrm{x} \mathrm{H}_2 \mathrm{O}_2+\mathrm{ClO}_4 \rightarrow \mathrm{x} \mathrm{O}_2+\mathrm{ClO}_2+2 \mathrm{H}_2 \mathrm{O}
$$
- A3
- B4
- C1
- Correct answerD2
Solution
$$
\mathrm{x} \mathrm{H}_2 \mathrm{O}_2+\mathrm{ClO}_4^{-} \rightarrow \mathrm{x} \mathrm{O}_2+\mathrm{ClO}_2^{-}+2 \mathrm{H}_2 \mathrm{O}
$$
Reduction Half Reaction
$$
\mathrm{ClO}_4^{-} \longrightarrow \mathrm{ClO}_2^{-}
$$
$$
4 \mathrm{e}^{-}+4 \mathrm{H}^{+}+\mathrm{ClO}_4^{-} \longrightarrow \mathrm{ClO}_2^{-}+2 \mathrm{H}_2 \mathrm{O}
$$
Oxidation Half Reaction,
$$
\begin{aligned}
& \mathrm{H}_2 \mathrm{O}_2 \longrightarrow \mathrm{O}_2 \\
& \mathrm{H}_2 \mathrm{O}_2 \longrightarrow \mathrm{O}_2+2 \mathrm{H}^{+}+2 \mathrm{e}^{-}
\end{aligned}
$$
Net Redox reaction
$$
\begin{aligned}
& {\left[4 \mathrm{e}^{-} 4 \mathrm{H}^{+}+\mathrm{ClO}_4^{-} \longrightarrow \mathrm{ClO}_2^{-}+2 \mathrm{H}_2 \mathrm{O}\right] \times 1} \\
& {\left[2 \mathrm{H}_2 \mathrm{O}_2 \longrightarrow \mathrm{O}_2+2 \mathrm{H}^{+}+2 \mathrm{e}^{-}\right] \times 2} \\
& 2 \mathrm{H}_2 \mathrm{O}_2+\mathrm{ClO}_4^{-} \longrightarrow 2 \mathrm{O}_2+\mathrm{ClO}_2^{-}+2 \mathrm{H}_2 \mathrm{O} \\
& \mathrm{x}=2
\end{aligned}
$$
Hence, the correct answer is option: 'D'.