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  INTERMOLECULAR FORCES:               (Van der waals, forces): Weak attractive forces which exist between the molecules are called intermolecular forces or often called van der waals forces. These forces are much weaker than ionic covalent or metallic bonding forces. Thus are three types of intermolecular forces:              (1)               Instantaneous (temporary) dipole-induced dipole forces. (2)               Dipole- dipole forces (permanent dipole forces) (3)               Hydrogen-bonding                          The increasing strength order of van der waals forces describes that hydrogen bonding is the strongest of all. Temporary dipole...