Question

Write chemical equation of the reaction of glucose with (i) Hydroxylamine, and (ii) Bromine water.

Hint:

Remember: Glucose behaves like an aldehyde, so it reacts with reagents like hydroxylamine and bromine water that test aldehyde functionality.

Answer 1

(i) Reaction of glucose with hydroxylamine:
Glucose reacts with hydroxylamine (\(NH_2OH\)) to form an oxime by reacting with the aldehyde group (-CHO) of glucose. \[ C_6H_{12}O_6 + NH_2OH \longrightarrow C_6H_{11}O_6{-}CH{=}NOH + H_2O \] (ii) Reaction of glucose with bromine water:
Glucose undergoes mild oxidation with bromine water, converting the aldehyde group (-CHO) into a carboxylic acid (-COOH), giving gluconic acid. \[ C_6H_{12}O_6 + Br_2 + H_2O \longrightarrow C_6H_{12}O_7 + 2HBr \] Conclusion:
- With hydroxylamine, glucose forms an oxime derivative.
- With bromine water, glucose is oxidized to gluconic acid.