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Question
Why is \[\ce{HCl}\] not used to make the medium acidic in oxidation reactions of \[\ce{KMnO4}\] in acidic medium?
Options
Both \[\ce{HCl}\] and \[\ce{KMnO4}\] act as oxidising agents.
\[\ce{KMnO4}\] oxidises \[\ce{HCl}\] into \[\ce{Cl2}\] which is also an oxidising agent.
\[\ce{KMnO4}\] is a weaker oxidising agent than \[\ce{HCl}\].
\[\ce{KMnO4}\] acts as a reducing agent in the presence of \[\ce{HCl}\].
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Solution
\[\ce{KMnO4}\] oxidises \[\ce{HCl}\] into \[\ce{Cl2}\] which is also an oxidising agent.
Explanation:
\[\ce{HCl}\] is not used to make the medium acidic in oxidation reactions of \[\ce{KMnO4}\] in acidic medium. The reason is that if \[\ce{HCl}\] is used, the oxygen produced from \[\ce{KMnO4 + HCl}\] is partly utilized in oxidizing \[\ce{HCl}\] to \[\ce{Cl}\], which itself acts as an oxidizing agent and partly oxidises the reducing agent.
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