Question

How sodium bicarbonate test is used to distinguish between carboxylic acid and phenol?

Answer 1

1. Carboxylic acid on treatment with NaHCO₃ gives brisk effervesce and CO₂ gas is evolved.
   \[\ce{RCOOH + NaHCO3 -> R-COONa + CO2↑ + H2O}\]
2. Phenol does not evolve C02 gas when treated with NaHC03 as it does not have a -COOH group.
   \[\ce{Phenol + NaHCO3 -> No reaction}\]