Question

The carbohydrate which does not react with ammoniacal \( AgNO_3 \) solution is:

• A. Sucrose
• B. Maltose
• C. Lactose
• D. Fructose

Hint:

Non-reducing sugars like sucrose do not react with Tollen’s reagent due to the absence of a free aldehyde or ketone group.

Answer 1

The Correct Option is A

Step 1: Understanding Tollen’s Test Ammoniacal silver nitrate (\( AgNO_3 \)) is used in Tollen’s test to detect reducing sugars. A reducing sugar has a free aldehyde or ketone group that can reduce \( Ag^+ \) to metallic silver. 

Step 2: Identifying Reducing and Non-Reducing Sugars - Sucrose is a non-reducing sugar because its glycosidic bond prevents the free aldehyde or ketone group from participating in the reaction. - Maltose, lactose, and fructose are reducing sugars, which means they react with ammoniacal \( AgNO_3 \). 

 

Step 3: Conclusion Since sucrose does not react with Tollen’s reagent, it is the correct answer.