What is a discriminating test for the presence of a carboxylic acid?

1 Answer
May 23, 2016

The classic test is the evolution of gas from when sodium bicarbonate is added.

Explanation:

Take an aqueous solution of the acid, treat this #NaHCO_3#, and the solution will effervesce.

#HCO_3^(-) + HO(O=)CR rarr CO_2(g)uarr + H_2O + ""^(-)O(O=)CR#

As with all chemical tests, you should do it first on an authentic carboxylic acid so that you know what constitutes a positive.