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Question
\[\ce{KMnO4}\] acts as an oxidising agent in acidic medium. The number of moles of \[\ce{KMnO4}\] that will be needed to react with one mole of sulphide ions in acidic solution is ______.
Options
`2/5`
`3/5`
`4/5`
`1/5`
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Solution
KMnO4 acts as an oxidising agent in acidic medium. The number of moles of \[\ce{KMnO4}\] that will be needed to react with one mole of sulphide ions in acidic solution is \[\ce{2/5}\].
Explanation:
\[\ce{2Mno^{-}4 + 5S^2 + 16H^- -> 2Min^{2+} + 5S + 8H2O}\]
For 5 mole of S the number of moles of \[\ce{KMnO4 = 2}\]
For 1 mole of S the number of moles of \[\ce{KMnO4 = 2/5}\]
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