Question

Glucose, on reduction with Na/Hg and water, gives-

• A. sorbitol
• B. fructose
• C. saccharic acid
• D. gluconic acid

Answer 1

The correct option is A

sorbitol

Explanation for correct answer:

Option (A) Sorbitol

• Glucose when reacts with Sodium - amalgam $(\mathrm{Na}-\mathrm{Hg})$ or Hydrogen $\left({\mathrm{H}}_2\right)$ which acts as reducing agents in the presence of a catalyst on reduction yields Alcohols (Sorbitol).

Explanation for incorrect answers:

Option (B) Fructose

• Glucose on reduction forms Sorbitol in the presence of the enzyme Aldol reductase and this Sorbitol is converted to Fructose in the presence of the enzyme Sorbitol dehydrogenase.

Option (C) Saccharic acid

• Glucose when oxidized with Nitric acid $\left({\mathrm{HNO}}_3\right)$, Saccharic acid is formed.

Option (D) Gluconic acid

• Glucose when reacts with Bromine $\left({\mathrm{Br}}_2\right)$ water, first Bromine water is converted to Hypobromous acid $\left(\mathrm{HOBr}\right)$ and then glucose is converted to Gluconic acid, where the aldehyde group is oxidized to carboxylic acid.
• $\underset{\mathrm{Bromine}}{{\mathrm{Br}}_2}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}}\to \underset{\mathrm{Hypobromous}\mathrm{acid}}{\mathrm{HOBr}}+\underset{\mathrm{Hydrogen}\mathrm{bromide}}{\mathrm{HBr}}$

Hence Option (A) Sorbitol is correct.