Exams › JEE Advanced › Chemistry
Correct answer: Sucrose
Cellobiose, lactose, and maltose all have one free anomeric carbon (C1-OH in glucose unit) that can open to the aldehyde form and reduce Fehling's/Tollens' reagent. Sucrose is formed by a 1,2-glycosidic bond between C1 of glucose and C2 of fructose, blocking both anomeric carbons. Therefore sucrose cannot open to an aldehyde form and is a non-reducing sugar.