-Why do some solids dissolve in water but others do not?
-Why are some substances gases at room temperature, but others are liquid or solid?
-What gives metals the ability to conduct electricity, what makes non-metals brittle?
The answers to these questions all have to do with:
INTERMOLECULAR FORCES
Intermolecular forces: is a general term describing the fact that all atoms, and molecules share a certain inherent attraction for each other