Write the mechanism of acid dehydration of ethanol to yield ethene.

(N/A) 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:
$CH_3-CH_2-OH + H^{+} \rightleftharpoons CH_3-CH_2-OH_2^{+}$
Step $2$: Formation of carbocation (rate-determining step):
$CH_3-CH_2-OH_2^{+} \rightarrow CH_3-CH_2^{+} + H_2O$
Step $3$: Elimination of a proton to form ethene:
$CH_3-CH_2^{+} \rightarrow CH_2=CH_2 + H^{+}$
The acid consumed in step $1$ is released in step $3$. After the formation of ethene,it is removed to shift the equilibrium in a forward direction.