Chapter 20.1, Problem 20.2P

Interpretation Introduction

(a)

Interpretation:

The monosaccharide, arabinose should be classified by the type of carbonyl group and the number of carbons in the chain.

Concept Introduction:

Monosaccharides in which the carbonyl group is at C-1 position are aldehydes and they are called aldoses. If the carbonyl group at C-2 position are ketones, they are called ketoses.

Monosaccharides can be classified by the number of carbons in the carbon chain.

3 C's − triose

4 C's − tetrose

5 C's − pentose

6 C's − hexose

In the classification of monosaccharides based on type of carbonyl group and number of carbons present in the chain, if the monosaccharide contains an aldehyde group, the prefix aldo- is added to the name and it is called an aldose. On the other hand, if a ketone group is present, it is a ketose or the prefix keto- is added.

Interpretation Introduction

(b)

Interpretation:

The monosaccharide, threose should be classified by the type of carbonyl group and the number of carbons in the chain.

Concept Introduction:

Monosaccharides in which the carbonyl group is at C-1 position are aldehydes and they are called aldoses. If the carbonyl group at C-2 position are ketones, they are called ketoses.

Monosaccharides can be classified by the number of carbons in the carbon chain.

3 C's − triose

4 C's − tetrose

5 C's − pentose

6 C's − hexose

In the classification of monosaccharides based on type of carbonyl group and number of carbons present in the chain, if the monosaccharide contains an aldehyde group, the prefix aldo- is added to the name and it is called an aldose. On the other hand, if a ketone group is present, it is a ketose or the prefix keto- is added.

Interpretation Introduction

(c)

Interpretation:

The monosaccharide, erythrulose should be classified by the type of carbonyl group and the number of carbons in the chain.

Concept Introduction:

Monosaccharides in which the carbonyl group is at C-1 position are aldehydes and they are called aldoses. If the carbonyl group is at C-2 position are ketones and they are called ketoses.

Monosaccharides can be classified by the number of carbons in the carbon chain.

3 C's − triose

4 C's − tetrose

5 C's − pentose

6 C's − hexose

In the classification of monosaccharides based on type of carbonyl group and number of carbons present in the chain, if the monosaccharide contains an aldehyde group, the prefix aldo- is added to the name and it is called an aldose. On the other hand, if a ketone group is present, it is a ketose or the prefix keto- is added.