Question

Neeta was experimenting in the lab to study the chemical reactivity of alcohol. She carried out a dehydration reaction of propanol at 140°C to 180°C. Different products were obtained at these two temperatures.

1. Identify the major product formed at 140°C and the mechanism followed in this case.
2. Identify the major product formed at 180°C.

Answer 1

1. Ethanol undergoes a dehydration reaction. At 140°C, diethyl ether is formed. The formation of ether is a nucleophilic S_N2 substitution bimolecular reaction.
2. When the temperature exceeds 170°C, ethene is the major product. Elimination, E₁ reaction.