Question

What type of force exists between two polar molecules?

Answer 1

London dispersion forces, under the category of van der Waalforces: These are the weakest of the intermolecular forces and exist between all types of molecules, whether ionic or covalent—polar or nonpolar. The more electrons amolecule has, the stronger the London dispersion forces are.

Intramolecular and intermolecular 

Answer 2

polar covalent force exists between two polar molecules