Examine the following structure.
${\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-\mathrm{CH}={\mathrm{CH}}_2$   and  ${\mathrm{CH}}_3-{\mathrm{CH}}_2-\mathrm{CH}=\mathrm{CH}-{\mathrm{CH}}_3$

which of the following correctly characterizes this structure?

Isomerism refers to two or more compounds that share the same chemical formula but have different structures and characteristics. 

The two types of isomerism are constitutional and stereoisomerism. 

Position isomerism can be seen in the two provided structures, Pent-1-ene and Pent-2-ene. 

Position isomerism is a property that occurs when distinct compounds from the same homologous series share the same chemical formula and carbon skeleton display.

$\begin{array}{rcl} & & \underset{\mathrm{Pent}-1-\mathrm{ene}}{{\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-\mathrm{CH}={\mathrm{CH}}_2}\end{array}$ 

$\begin{array}{rcl} & & \underset{\mathrm{Pent}-2-\mathrm{ene}}{{\mathrm{CH}}_3-{\mathrm{CH}}_2-\mathrm{CH}=\mathrm{CH}-{\mathrm{CH}}_3}\end{array}$