In which of the following reactions, hydrogen peroxide acts as an oxidizing agent ?

Options

A. `HOCl + H_(2)O_(2) to H_(3)O^(+) +Cl^(-)+ O_(2)`
B. `I_(2)+H_(2)O_(2)+2OH^(-)to2I^(-)+2H_(2)O+O_(2)`
C. `2MnO_(4)^(-)+3H_(2)O_(2)to2MnO_(2)+3O_(2)+2H_(2)O+2OH^(-)`
D. `PbS+4H_(2)O_(2)toPbSO_(4)+4H_(2)O`

Answer

D

Explanation

Notice that the oxidation state of oxygen goes from -1 on the `H_(2)O` 2 to -2 on the `H_(2)O` means `H_(2)O_(2)` is being reduced. On the other hand the oxidation state of sulfur is going from - 2 on the PbS to +6 on the `PbSO_(4)`. i.e Sulfur is being oxidised.