Question

With which of the following reagents glucose does not react?
(correct answer +1, wrong answer -0.25)

• A. $HI$
• B. $NaHS{O}_3$
• C. $B{r}_2,H_{2}O$
• D. $A{c}_{2}O$

Answer 1

The correct option is B $NaHS{O}_3$

Simple aldehyde reacts with sodium bisulphite and this helps in detection, seperation and classification of aldehydes.
However, $CHO$ group in glucose is not free but it is involved in hemiacetal formation with $C-5$. Hence, it does not show reaction with $NaHS{O}_3$. Also steric crowding in glucose inhibit the reaction to happen.