Question

Write chemical equation and mechanism of acid catalysed hydration of Alkene.

Hint:

Always apply Markovnikov’s rule: “In hydration of alkenes, H attaches to the carbon with more hydrogens.”

Answer 1

Step 1: General chemical equation.
Acid-catalysed hydration of alkenes follows Markovnikov’s rule. Example with ethene: \[ CH_2 = CH_2 + H_2O \;\xrightarrow{H_2SO_4}\; CH_3CH_2OH \] Step 2: Mechanism.
\begin{enumerate} \item
Protonation of alkene: \[ CH_2 = CH_2 + H^+ \;\longrightarrow\; CH_3-CH_2^+ \] (formation of carbocation) \item
Nucleophilic attack by water: \[ CH_3-CH_2^+ + H_2O \;\longrightarrow\; CH_3-CH_2OH_2^+ \] \item
Deprotonation: \[ CH_3-CH_2OH_2^+ \;\longrightarrow\; CH_3-CH_2OH + H^+ \] \end{enumerate} Conclusion:
The final product is an alcohol, and the reaction is catalysed by an acid (usually \(H_2SO_4\)).