Question

Phenol can be distinguished from ethanol by the reaction with _________.

• A. neutral $FeC{l}_3$
• B. hot alkaline $KMn{O}_4$
• C. cold alkaline $KMn{O}_4$
• D. $Na$ in ammonia

Answer 1

The correct option is A neutral $FeC{l}_3$

Phenols react with FeCl3 to form a colored complex with the Fe3+ ion. The color varies from purple to orange depending on the structure of the phenol tested.

Alcohols do not form colored complexes with iron ion. In this test, the appearance of a color is taken as a positive test and it indicates that phenol was present in the original solution.