Question

Hydrogen peroxide acts both as an oxidising and as a reducing agent depending upon the nature of the reacting species. In which of the following cases $H_2O_2$ acts as a reducing agent in acid medium ?

• A. $MnO^{-}_{4}$
• B. $Cr_{2}O^{2-}_{7}$
• C. $SO^{2-}_{3}$
• D. $KI$

Answer 1

Answer: (A)

$MnO^{-}_{4}$

Answer 2

$H _{2} O _{2}+ MnO _{4}^{-} {->[]\overset{\oplus}{H}} O _{2}+ Mn ^{+2}$