Rank the following compounds in order of increasing strength of intermolecular forces: CH3Cl, NaCl, CH3OH?

CH3Cl < CH3OH < NaCl

Explanation:

The intermolecular forces are the forces that join together the ions, metals, or molecules in a substance. At a metallic substance, the forces involved are the metallic forces. In the ionic compounds, the forces are the ion-ion forces, and at molecular compounds, there're three different types of forces.

The intermolecular forces of a molecule can be the London force, dipole-dipole force or hydrogen bond. The London force happens in nonpolar substances, the dipole-dipole forces at polar substances, and the hydrogen bond, at polar substances that have the hydrogen-bonded to a high electronegative element (N, O, or F).

The order of increasing strength is:

London force < dipole-dipole < hydrogen bond < metallic < ion-ion.

CH3Cl is a polar molecule because its dipole moment is different from 0 (the dipole of C-Cl is strong than the dipole of C-H so they don't cancel each other). Thus, it has dipole-dipole forces.

NaCl is an ionic compound formed by the ions Na + and Cl-, so it has ion-ion forces. Ah CH3OH is a polar molecule, in which the hydrogen is bonded to oxygen, so it has hydrogen bonds. The increasing strength of intermolecular forces is:

CH3Cl < CH3OH < NaCl