Chapter 23, Problem 53A

Interpretation Introduction

Interpretation:

The name of two isomers of glucose should be determined.

Concept introduction:

The compounds having similar chemical formula but different structures are known as isomers.

The compounds having similar chemical or molecular formula but different connectivity is known as constitutional isomers.

Answer to Problem 53A

The two isomers of glucose are Fructose and Galactose.

Explanation of Solution

Glucose consists of single unit of sugar which can’t be hydrolyzed into simpler molecule. Glucose is obtained by the photosynthesis process and also found in plants.

The structure is:

The two structural isomers of glucose are fructose and galactose. The molecular formula of fructose and galactose is same with the glucose whereas the structural formula of both fructose and galactose is different with glucose.

The molecular formula of glucose = ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{O}}_{\text{6}}$

The molecular formula of fructose = ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{O}}_{\text{6}}$

The molecular formula of galactose = ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{O}}_{\text{6}}$

The structure of glucose, fructose and galactose is:

In galactose, the hydroxyl group linked with forth carbon atom of the chain is present on left side whereas in glucose, the hydroxyl group linked with forth carbon atom of the chain is present on right side.

In fructose, ketone group is linked with second carbon atom of the chain.