Chapter 23.1, Problem 7R

To determine

To write: The formulas for adding one, two, and three more double bonds to octene ${\text{C}}_8{\text{H}}_{16}$ , which has been made by adding one double bond to octane ${\text{C}}_8{\text{H}}_{18}$ .

To identify the trend in which number of hydrogen atoms decreases for each double bond added.

Explanation of Solution

Introduction:Hydrocarbons containing double bonds between carbon atoms are classified as unsaturated hydrocarbons.

Adding one double bond to octane ${\text{C}}_8{\text{H}}_{18}$ makes the hydrocarbon octene ${\text{C}}_8{\text{H}}_{16}$ .

Adding another double bond to octane, gives the structural formula:

The formula of the new hydrocarbon compound is ${\text{C}}_8{\text{H}}_{14}$

Adding the third double bond to octane:

The formula of new hydrocarbon compound is ${\text{C}}_8{\text{H}}_{12}$

Adding the fourth double bond to octane:

The formula of the new hydrocarbon compound is ${\text{C}}_8{\text{H}}_{10}$

Considering the new compounds formed, for each double bond added to octane, there is a decrease of two hydrogen atoms.

Conclusion:

Octene ${\text{C}}_8{\text{H}}_{16}$ is made by adding a double bond to octane ${\text{C}}_8{\text{H}}_{18}$ .

Adding one, two, and three more double bonds to octane gives the hydrocarbons ${\text{C}}_8{\text{H}}_{14}$ , ${\text{C}}_8{\text{H}}_{12}$ , and ${\text{C}}_8{\text{H}}_{10}$ respectively. For each double bond added to octane, there is a decrease of two hydrogen atoms.