Final answer:
Intermolecular forces are the electrostatic interactions between molecules. They are weaker than intramolecular forces and determine many physical properties of compounds.
Step-by-step explanation:
Intermolecular forces are the electrostatic interactions between molecules. These forces are weaker than the intramolecular forces that hold atoms together within a molecule. The major types of intermolecular forces include dipole-dipole interaction, hydrogen bonding, and London dispersion forces. These forces play a crucial role in determining the physical properties of compounds, such as boiling point, melting point, and solubility.