Question

Consider the following organic compounds:
\[ C_2H_5CHO, \, CH_3COOH, \, C_2H_5OH, \, CH_3COCH_3 \]
Which one of these compounds, when heated at 443 K in excess conc. \(\text{H}_2\text{SO}_4\), forms ethene as its major product? State the role of conc. \(\text{H}_2\text{SO}_4\) in the reaction. Also, write the chemical equation for the chemical reaction involved.

Answer 1

Compound forming ethene:

Ethanol (\(C_2H_5OH\)) forms ethene when heated at 443 K in the presence of excess concentrated sulphuric acid.

Role of conc. \(H_2SO_4\):

Concentrated sulphuric acid acts as a dehydrating agent in this reaction. It removes a molecule of water from ethanol to form ethene.

Chemical equation:

\[ C_2H_5OH \xrightarrow{\text{conc. } H_2SO_4, \, 443 K} C_2H_4 + H_2O \]