Question

Both glucose and sucrose give Fehling's test.

• A. True
• B. False

Answer 1

The correct option is B False

fructose give positive result in fehling test but sucrose give negative result. this is because of the presence of free aldehydic group in fructose (through Lobry de Bruyn and van Ekenstein rearrangement), hence fructose give +ve fehling test. Further since in Sucrose, as reducing groups of glucose and fructose are involved in glycosidic bond formation, sucrose is a non-reducing sugar and hence dont give Fehling test.