Question

Write chemical test to distinguish between carbolic acid and alcohol.

Answer 1

Action of neutral ferric chloride (FeCl₃) is a distinguishing test (colour test) between phenol and an alcohol.
1. Action on phenol: When phenol is treated with aqueous neutral FeCl₃, it gives red to violet colouration. The colour obtained is due to the formation of violet
coloured ferric phenoxide complex.

2. Action on alcohol: When an alcohol (eg. ethanol) is treated with aqueous neutral FeCl₃, it does not give any colouration.
Ethanol + aq./neutral FeCl₃ → No colouration