A force acting between two different molecules
London forces, dipole attractions and hydrogen bonding are some of the examples for intermolecular attractions in the order of increasing strength.
intermolecular force
This is an intermolecular force.
Gravity!
Boiling point is a property not a force; but a high boiling point indicate a strong intermolecular force.
Intermolecular attraction
The intermolecular force in Ar (argon) is London dispersion forces, which are the weakest type of intermolecular force. This force is caused by temporary fluctuations in electron distribution around the atom, leading to temporary dipoles.
Intramolecular forces are not intermolecular forces !
The intermolecular force in BF3 is London dispersion forces. This is because BF3 is a nonpolar molecule, so the only intermolecular force it experiences is the temporary weak attraction between temporary dipoles.
Intermolecular forces shown by the dotted lines not by strong covalent bonds.
Hydrogen bonds
The strongest intermolecular force present in hydrogen bromide (HBr) is dipole-dipole interaction.