Question

(a) Giving a chemical equation for the following process :

Decarboxylation.

(b) State chemical tests to distinguish between the following pairs of compounds :

Phenol and Benzoic acid.

Answer 1

(a) Decarboxylation : Sodium or potassium salt of carboxylic acids on heating with soda lime (NaOH and CaO), loses a molecule of carbon dioxide and alkanes are obtained as products.

(b) Phenol and Benzoic acid : Phenol and benzoic acid can be distinguished by their reactions with sodium bicarbonate solution. Benzoic acid will give effervescence with NaHCO₃ but phenol will not react.