Question

Describe the preparation of potassium permanganate from pyrolusite ore. write balanced chemical equation for one reaction to show the oxidizing nature of potassium permanganate

Answer 1

Hey !!

Potassium permanganate is prepared from pyrolusite ore with KOH in the presence of oxidising agent like KNO₃. The dark green potassium manganate undergoes electrolytic oxidation to produce potassium permanganate.

2MnO₂⁻ + 4KOH + O₂ -----> 2K₂MnO₄ + 2H₂O

3MnO₂⁻ + 4H⁺ -----> 2MnO₄ + MnO₂ + 2H₂O

Oxidising nature of potassium permanganate can be shown as:-

 MnO₄⁻ + 8H⁺ + 5e⁻ -----> Mn²⁺ + 4H₂O

                           [ Fe²⁺ ---> Fe³⁺ + e⁻ ] × 5

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MnO₄⁻ + 5Fe²⁺ + 8H⁺ ----> Mn²⁺ + 5Fe³⁺ + 4H₂O

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GOOD LUCK !!