By reacting both i.e alcohol ans carboxylic acid with SODIUM CARBONATE or SODIUM BICARBONATE.
take a small amount of each compound in a test tube and add to it an aq. solution of NaHCO∨3. The compound which produces brisk effervescence due to the evolution of carbon dioxide must be a carboxylic acid.
soap molecule has two parts i.e the hydrocarbon and the ionic part.
The hydrocarbon part is soluble in oil while the ionic part is soluble in water. Most of the dirt is oily in nature. therefore when soap is applied, the molecules align themselves around the dirt in such a manner that the hydrophobic (hydrocarbon) part sticks towards the dirt while the hydrophilic (ionic) part dissolves in water facing outside forming a cluster called micelle .
when the cloth is agitated, the micelle along with the dirt particle gets separated by the cloth due to inertia.