Question

Assertion (A): Glucose gets oxidized to six carbon gluconic acid on reaction with bromine water. Reason (R): The carbonyl group is absent in the open chain structure of glucose. Choose the correct option:

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false, but Reason (R) is true.

Hint:

Glucose reactions: Bromine water → oxidizes aldehyde to gluconic acid Shows presence of carbonyl group in open-chain form.

Answer 1

The Correct Option is C

Concept: Bromine water is a mild oxidizing agent that oxidizes aldehydes (–CHO) to carboxylic acids (–COOH) without affecting other functional groups.
Step 1: Check Assertion (A). Glucose contains an aldehyde group in its open-chain form. Bromine water oxidizes the aldehyde group to gluconic acid, which still contains six carbon atoms. Hence, Assertion is true.
Step 2: Check Reason (R). In the open-chain structure of glucose, a carbonyl group (aldehyde) is present. So, the statement that carbonyl group is absent is incorrect. Reason is false.
Step 3: Choose correct option. Assertion is true but Reason is false.