Write the mechanism of dehydration of ethanol.

Explanation

The mechanism of acid dehydration of ethanol to yield ethene involves the following three steps:
Step-1: Protonation of ethanol to form ethyl oxonium ion:
ltBrgt Step-2:
`H-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-overset(H)overset(|)(O^(+))-Hoverset("Slow")hArrH-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C^(+))+H_(2)O`
Step-3: Elimination of a proton to form ethene

the Acid consumed in step-1 is released in step-3. After the formation of ehtnene. It is removed to shift the equilibrium in a forward direction.