Bond polarity and intermolecular forces

There are three types of nonbonding intermolecular interaction dipole-dipole interactions, van der Waals forces and hydrogen bonding. These interactions increase significantly as the molecular weights increase, and also increase with increasing polarity of the molecules. 

The arrow indicates the electrons are towards the more electronegative atom fluorine. The and 8 symbols indicate partial positive and negative charges. 

Relatively weak forces of attraction that exist between nonpolar molecules are called van der Waals forces or London dispersion forces. Dispersion forces between molecules are much weaker than the covalent bonds within molecules. Electrons move continuously within bonds and molecules, so at any time one side of the molecule can have more electron density than the other side, which gives rise to a temporary dipole. Because the dipoles in the molecules are induced, the interactions between the molecules are also called induced dipole-induced dipole interactions. 

---

Would you expect lithium chloride to dissolve in toluene No, LiCl is not soluble in toluene. LiCl and CgH CHg differ widely in bonding, polarity, and intermolecular forces. 

---