Chapter 22, Problem 42A

Interpretation Introduction

Interpretation- To determine the condensed structural formula for pentane and hexane.

Concept Introduction- The condensed structural formula is the shorthand structural formula of organic molecules where some bonds or atoms are not mentioned. The formula is written in a line form.

Example: ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{3}}$

Answer to Problem 42A

The condensed formula of pentane is ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{3}}$ and hexane is ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{3}}$ .

Explanation of Solution

Pentane contains five carbon atoms and twelve hydrogen atoms. There are four carbon-carbon bonds and twelve carbon-hydrogen bonds. Hence, the condensed structural formula of pentane is ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{3}}$ .

Hexane contains six carbon atoms and fourteen hydrogen atoms. It has five carbon-carbon bonds and fourteen carbon-hydrogen bonds. Hence, the condensed structural formula of hexane is ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{3}}$ .