Q.Glucose and fructose can be distinguished by which of the following reagents?

Br2/H2O is a mild oxidant that oxidises only aldoses; glucose (aldose) reacts, fructose (ketose) does not, so bromine water distinguishes them. Correct option (c).

Glucose is an aldohexose (has -CHO), fructose is a ketohexose (has >C=O). Bromine water is a mild oxidising agent specific to the aldehyde group: it oxidises glucose's -CHO to -COOH (gluconic acid, decolourising the bromine), but it cannot oxidise fructose's keto group. So Br2/H2O gives a positive result only with glucose.

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