9.25 Write chemical reactions to justify that hydrogen peroxide can function as an oxidising as well as reducing agent.


 Hydrogen peroxide, H2O2 acts as an oxidizing as well as a reducing agent in both acidic and alkaline media.

Reactions involving oxidizing actions are: 

1) 2Fe2+  + 2H+  + H2O2       2Fe3+   +   2H2O
2) Mn2+ + H2O2  Mn4+  + 2OH-
3) PbS + 4H2O2    PbSO4  + 4H2O
4) 2Fe2+ + H2O2     2Fe3+ + 2OH-

 

Reactions involving reductions are;

1) 2MnO-4 + 6H+ + 5H2O2      2Mn2+  + 8H2O + 5O2
2) I2  + H2O2 + 2OH-    2I- + 2H2O + O2
3) HOCI + H2O2     H3O+ + Cl- + O2
4) 2MnO-4 + 3H2O2   2MnO2 + 3O2 + 2H2O + 2OH-