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A solution of KMnO(4) on reduction yield...

A solution of `KMnO_(4)` on reduction yields either a colourless solution or a brown precipitate or a green solution depending on pH of the solution. What different stages of the reduction do these represent and how are they carried out?

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Oxidising behaviour of `KMnO_(4)` depends on pH of the solution.
In acidic medium `(pH lt 7)`
`MnO_(4)^(-) + 8H^(+) + 5e^(-) rarrunderset("Colourless")(Mn^(2+))+4H_(2)O`
In alkaline medium `(pH gt 7)`
`MnO_(4)^(-) + e^(-) rarrunderset(("Green"))(MnO_(4)^(2-)`
In neutral medium (pH = 7)
`MnO_(4)^(-)+2H_(2)O + 3e^(-)rarrunderset(("Brown ppt"))(MnO_(2)) + 4OH^(-)`
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