Question

what you mean by intermolecular force how this was related to three States of matter

Answer 1

Intermolecular forces are forces acting between the molecules of matter. Because of these forces molecules are attached to one another. Greater the attraction between the molecules lesser will be the space between them and higher will be the density of matter. So,following is the strength of intermolecular forces between the various states of matter.
i.e. solid> liquid> gas