Intermolecular forces are of the type(1) hydrogen bonds
(2) dipole-dipole attractions
(3) dispersion forces (van der Waals, etc.)
Hydrogen bonds can be considered as the strongest intermolecular attraction forces.
Hydrogen bonds are much stronger than other intermolecular forces.
polar molecules
The main intermolecular forces between water molecules are hydrogen bonds which are pretty strong as far as intermolecular forces go. Between hydrocarbon chains (oil) the main intermolecular force are London force which are weaker. For two liquids to be miscible the intermolecular forces between them have to be similar in strength or they won't dissolve. Water and oil have different strengths of intermolecular bonds so don't mix.
Van der Waal's bonds are the weakest of the types of intermolecular bonds.
hydrogen bonds
Hydrogen bonds can be considered as the strongest intermolecular attraction forces.
Intramolecular forces are not intermolecular forces !
hydrogen bonding
Intermolecular forces are based on electrostatic attraction and/or polarisation phenomena. Intramolecular bonds involve covalent bonds, polar or non-polar.
These are intermolecular forces.
Hydrogen bonds are much stronger than other intermolecular forces.
Hydrogen bonds
intermolecular forces
Ionic bonds create stronger intermolecular attraction than covalent bonds do; that is why rocks are harder than plastic.
Intermolecular forces shown by the dotted lines not by strong covalent bonds.
Hydrogen bonds can be considered as the strongest intermolecular attraction forces.