Forces of Attraction in different states of matter.

[Elsa1234]

We are taught that the forces of attraction in a liquid are lesser than those in a solid. What is the reason? Is it because the intermolecular spaces are large or is it because the individual attractive force of the molecule is less?

 

[Borek]

What is the reason?

That's putting cart before the horse.

Doesn't matter what the reason is (and it can be anything that describes the molecules interactions). Whether the substance is solid or liquid is the RESULT of the attractive forces. For a given pair of molecules the attractive force is what it is - if it is strong enough, the mixture will be solid, if it is too weak it will be a liquid. Molecules don't decide "we will be a liquid" and then look for a way to choose a correct intermolecular forces to fit the idea.