Question

Why is sulphuric acid not used during the reaction of alcohols with KI?

Answer 1

Alcohols, when treated with KI in presence of acidic medium yields Alkyl Iodide.

In acidic medium, KI transforms to HI,
2KI + H2SO4 → 2KHSO4 + 2HI

HI in turn react with alcohols to form alkyl iodide.
However, H2SO4 is an oxidizing agent.
Hence, it oxidizes the HI formed into I2.
2HI + H2SO4 → I2 + SO2 + H2O

So, there is no HI left for further reaction.
Therefore, H2SO4 is not used in the reaction.

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