MHT CET202520 Apr 2025Morning ShiftChemistryBiomoleculesActual
Which from following tests confirms presence of aldehydic group in glucose ?
Options
- AFormation of oxime when reacted with NH ₂ OH .
- BFormation of gluconic acid when reacted with Br ₂ water.
- CFormation of saccharic acid when glucose and gluconic acid treated with dil HNO ₃ -
- DFormation of penta acetate when treated with acetic anhydride.
Correct answer
B. Formation of gluconic acid when reacted with Br ₂ water.
Step-by-step solution
Identifying the aldehyde group in glucose requires a test specific to aldehydes that distinguishes them from ketones. Glucose contains both an aldehyde and multiple hydroxyl groups. Bromine water ( Br ₂ ) serves as a mild oxidizing agent that selectively oxidizes the aldehyde group ( -CHO ) to a carboxylic acid ( -COOH ), forming gluconic acid. Ketones remain unaffected by this reagent, making this reaction specific for aldehydes. While hydroxylamine ( NH ₂ OH ) forms an oxime with carbonyl groups, it reacts with b