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प्रश्न
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with SO2? Write the ionic equation for the reaction.
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उत्तर
Potassium permanganate can be made by the following methods:
It is produced industrially by the alkaline oxidative fusion of MnO2 followed by the electrolytic oxidation of manganate (VI).
\[\ce{MnO2 ->[Fused with KOH, oxidised with air or KNO3] \underset{manganate ion}{MnO^2-_4}}\]
\[\ce{\underset{manganate}{MnO^2-_4} ->[Electrolytic oxidation in alkaline solution] \underset{permanganate ion}{MnO^-_4}}\]
The chemical reactions of acidic potassium permanganate are as follows:
\[\ce{2MnO^-4 + 2H2O + 5SO2 -> 2Mn^2+ + 4H^+ + 5SO^2-_4}\]
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संबंधित प्रश्न
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