Question

Hydrogen peroxide acts both as an oxidizing agent and as a reducing agent in alkaline solution towards certain first row transition metal ions. Illustrate both these properties of H₂O₂ using chemical equations.

Answer 1

Oxidising agent: 

2Cr(OH)₃ + 4NaOH + 3H₂O₂ → 2Na₂CrO₄ + 8H₂O 

Here, Cr³⁺ gets oxidized to Cr⁶⁺ 

Reducing agent: 

2K₃[Fe(CN)₆] + 2KOH + H₂O₂ → 2K₄[Fe(CN)₄] + 2H₂O + O₂ 

Here, Fe³⁺ gets reduced to Fe²⁺.