Chapter 22, Problem 86A

a.

Interpretation Introduction

Interpretation: To interpret the graph give the number of constitutional isomers for the given carbon atoms.

Concept Introduction: In constitutional isomers, the compound has the same molecular formula but the arrangement of atoms is different.

Answer to Problem 86A

For five carbon atoms, the number of constitutional isomers is 5.

For seven carbon atoms, the number of constitutional isomers is 9.

For eight carbon atoms, the number of constitutional isomers is 18.

For nine carbon atoms, the number of constitutional isomers is 35.

For ten carbon atoms, the number of constitutional isomers is 75.

Explanation of Solution

The graph shows the study between the number of carbon atoms and the number of constitutional isomers which shows that on increasing the number of carbon atoms, the constitutional isomers increase.

Thus, for five carbon atoms, the number of constitutional isomers is 5.

For seven carbon atoms, the number of constitutional isomers is 9.

For eight carbon atoms, the number of constitutional isomers is 18.

For nine carbon atoms, the number of constitutional isomers is 35.

For ten carbon atoms, the number of constitutional isomers is 75.

b.

Interpretation Introduction

Interpretation: To give the change in the number of isomers between different carbon atoms.

Concept Introduction: In constitutional isomers, the compound has the same molecular formula but the arrangement of atoms is different.

Answer to Problem 86A

In alkanes, as the number of carbon atoms increases or the size of the molecule gets larger, then the formation of constitutional isomers also increases dramatically.

Explanation of Solution

In alkanes, as the number of carbon atoms increases or the size of the molecule gets larger, then the formation of constitutional isomers also increases dramatically.

For example, the difference between the number of constitutional isomers in the case of seven and eight carbon atoms is nine while the difference between the number of constitutional isomers in the case of nine and ten carbon atoms is forty, this shows that on increasing the number of carbon atoms, the constitutional isomers also increase.