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JEE MAIN 2021
25-07-21 S2
Question
Identify the process in which change in the oxidation state is five :
Select the correct option:
A
$\mathrm{Cr}_2 \mathrm{O}_7^{2-} \rightarrow 2 \mathrm{Cr}^{3+}$
B
$\mathrm{MnO}_4^{-} \rightarrow \mathrm{Mn}^{2+}$
C
$\mathrm{CrO}_4^{2-} \rightarrow \mathrm{Cr}^{3+}$
D
$\mathrm{C}_2 \mathrm{O}_4^{2-} \rightarrow 3 \mathrm{CO}_2$
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
Solution
MnO₄⁻ + 5e⁻ → Mn²⁺
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