Question

Which from following reactions confirms presence of one carbonyl group in glucose?

• A. When glucose is heated with HI for longer time forms n-Hexane.
• B. When glucose is heated with hydroxyl amine forms glucose oxime.
• C. When glucose is heated with excess acetic Anhydride forms glucose pentaacetate.
• D. When glucose is treated with dilute nitric acid forms saccharic acid.

Hint:

Oxime formation with hydroxylamine is a typical carbonyl test.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept
Carbonyl groups react with hydroxylamine to give oximes.

Step 2: Check each reaction
Heating with HI gives n-hexane, showing a straight six-carbon chain.
Reaction with acetic anhydride shows five OH groups.
Nitric acid oxidation to saccharic acid shows a CHO and a primary OH.

Step 3: Conclusion
Glucose oxime formation confirms the presence of a carbonyl group.

Final Answer:
Formation of glucose oxime with hydroxylamine confirms the carbonyl group. \[ \boxed{\text{(B) }\text{When glucose is heated with hydroxyl amine forms glucose oxime.}} \]