Question

Monosaccharides are called reducing sugar but disaccharides are not why

Answer 1

because Monosaccharides have free aldehyde or ketone group while disaccharides don't have.

Answer 2

Answer:

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Monosaccharides are called reducing sugars because monosaccharides contain free aldehydic or ketonic group. On the other hand, disaccharides do not have free aldehydic or ketonic group. Example of reducing sugars is maltose. Example of non-reducing sugars is sucrose.