Answer:
Because these three have different arrangements of [tex]-CH_{3}[/tex]
Explanation:
All of these alkanes: [tex]C_{5} H_{12}[/tex] Pentane, Isopentane, and Neopentane despite being homologous have the same chemical formula and their bonding rearranged, with branches of [tex]-CH_{3}[/tex] differently placed what gives them different physical and chemical properties such as melting and boiling points different.