In this lecture, we will learn how to distinguish between ALDEHYDES and KETONES through Tollens test and Fehling test. This video was created in accordance with the latest syllabus for CBSE Class 12 Chemistry – Aldehydes & Ketones published by Brilliant Qatar.
Fehling test is one of the most common tests used for the estimation or identification of reducing sugar and non-reducing sugars. This test by the German chemist H.C. Von Fehling is often used to distinguish between functional groups of ketones and carbohydrates that are water-soluble.
Tollens’ test, also known as silver-mirror test, is a qualitative laboratory test used to distinguish between an aldehyde and a ketone. It exploits the fact that aldehydes are readily oxidized (see oxidation), whereas ketones are not. Tollens’ test uses a reagent known as Tollens’ reagent, which is a colorless, basic, aqueous solution containing silver ions coordinated to ammonia [Ag(NH3)2+] .
