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प्रश्न
When \[\ce{KMnO4}\] solution is added to oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time because ______.
पर्याय
\[\ce{CO2}\] is formed as the product.
Reaction is exothermic.
\[\ce{MnO^{-}4}\] catalyses the reaction.
\[\ce{MnO^{2+}}\] acts as autocatalyst.
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उत्तर
When \[\ce{KMnO4}\] solution is added to oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time because \[\ce{MnO^{2+}}\] acts as autocatalyst.
Explanation:
When \[\ce{KMnO4}\] solution is added to oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time because \[\ce{Mn^{2+}}\] acts as an autocatalyst.
Reduction half \[\ce{Mno^{-}4 + 8H^+ + 5e^- -> Mn^{2+} + 4H2O] × 2}\]
Oxidation half \[\ce{C2O^{2-}4 -> 2CO2 + 2e] × 5}\]
Overall equation \[\ce{2Mno^{-}4 + 16H^+ + 5C2O^{2-}4 -> 2Min^{2+} + 10CO2 + 8H2O}\]
End point of this reaction Colourless to light pink.
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संबंधित प्रश्न
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Cr | Mn | Fe | Co | Ni | Cu |
| -0.91 | -1.18 | -0.44 | -0.28 | -0.25 | -0.34 |
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| Al | - 1.66 | +0.55 |
| Tl | + 1.26 | -0.34 |
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