The strongest intermolecular interactions between pentane (C5H12) molecules arise from b) London dispersion forces.
Pentane is a nonpolar molecule, meaning it does not have a permanent dipole moment. The intermolecular forces present in nonpolar substances like pentane are primarily London dispersion forces, which occur due to the temporary fluctuations in electron density that create instantaneous dipoles. These temporary dipoles can induce dipoles in neighboring molecules, resulting in an attraction between them.
In contrast:
- a) Dipole-dipole forces are not relevant here since pentane lacks the permanent dipoles required for this type of interaction.
- c) Hydrogen bonding occurs when hydrogen is bonded to highly electronegative atoms (like O, N, or F), which is not applicable to pentane.
- d) Ion-dipole interactions involve ions interacting with polar molecules, which is again not relevant for a nonpolar molecule like pentane.
- e) Carbon-carbon bonds are covalent bonds within the molecule itself and pertain to the intramolecular rather than intermolecular interactions.
Thus, the correct answer emphasizing the nature of interactions within pentane molecules points to London dispersion forces as the dominant form of attraction.