Chapter 22, Problem 69A

Interpretation Introduction

(a)

Interpretation:

The structural formulas for all structural isomers of molecules with formula ${\text{C}}_{\text{3}}{\text{H}}_{\text{8}}\text{O}$ need to be determined.

Concept introduction:

In organic compounds, isomers are compounds with same molecular formula but different arrangement of atoms.

Explanation of Solution

The given formula of molecule is ${\text{C}}_{\text{3}}{\text{H}}_{\text{8}}\text{O}$.

There is 1 oxygen atom thus, the possible functional group can be −OH group, ketone and ether.

The general formula of ketone is as follows:

${\text{C}}_n{\text{H}}_{2n}\text{O}$

Thus, for 3 carbon atoms, number of H atoms should be 6 but this is not true for the given formula of molecule. Thus, ketone cannot be formed. The possible functional groups will be only −OH and ether.

The structural formulas of all the isomers are represented as follows:

Interpretation Introduction

(b)

Interpretation:

The structural formulas for all structural isomers of molecules with formula ${\text{C}}_2{\text{H}}_4{\text{Cl}}_2$ need to be determined.

Concept introduction:

In organic compounds, isomers are compounds with same molecular formula but different arrangement of atoms.

Explanation of Solution

The given formula of molecule is ${\text{C}}_2{\text{H}}_4{\text{Cl}}_2$.

From the given formula, there are 2 carbon atoms in the main chain. There are 4 H atoms and 2 Cl atoms thus, the isomers will have different positions of Cl atoms in the main carbon chain.

The possible structural isomers are as follows: