What is the product obtained when glucose is reduced in the presence of sodium amalgam? 

Sorbitol 

The correct answer is option 3. Sorbitol.

When glucose is reduced in the presence of sodium amalgam, the product obtained is Sorbitol.

Reduction of Glucose: When glucose undergoes reduction, the aldehyde group (\(-CHO\)) at the first carbon is reduced to a primary alcohol group (\(-CH_2OH\)).

Sodium Amalgam: This is a reducing agent that provides the necessary electrons for the reduction process.

Process: Glucose is an aldohexose, meaning it has an aldehyde group at carbon 1 and hydroxyl groups on the other carbons.

Reduction Reaction: The aldehyde group (\(-CHO\)) of glucose is reduced to an alcohol group (\(-CH_2OH\)).

Sorbitol Formation: This reaction converts the aldehyde group of glucose to an additional hydroxyl group, resulting in sorbitol (a sugar alcohol).

Summary of Options:

Gluconic Acid: Formed by the oxidation of glucose, not reduction.

Glucaric Acid: Formed by the oxidation of glucose at both the aldehyde group and the primary alcohol group.

Sorbitol: Formed by the reduction of the aldehyde group of glucose to an alcohol group.

Hexane: Not related to the reduction of glucose.

Thus, the correct product obtained when glucose is reduced in the presence of sodium amalgam is: Sorbitol.