Concept:At elevated temperatures, concentrated sulfuric acid acts as a powerful dehydrating agent, forcing an intramolecular elimination (\(\beta\)-elimination) reaction.
Formula:$$ \text{CH}_3\text{-CH}_2\text{OH} \xrightarrow[170^{\circ}\text{C}]{\text{Conc. H}_2\text{SO}_4} \text{CH}_2\text{=CH}_2 + \text{H}_2\text{O} $$
Solution:- The high temperature (170°C) provides enough activation energy to cleave both the C-OH bond and a C-H bond on the adjacent beta-carbon of the same molecule.
- A carbon-carbon double bond forms to satisfy valency, yielding an alkene.
- For ethyl alcohol, the resulting alkene is ethene.
Why other options are incorrect:Ether is formed at lower temperatures (140°C). Esterification requires a carboxylic acid. Ethane requires reduction (hydrogenation), not dehydration.
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