Intermolecular Forces are forces which exist between two molecules which attract them to each other. There are four intermolecular forces which may exist between two molecules, depending on their polarity and the atoms that make up the molecules. These forces are London Dispersion, Dipole-Dipole, Hydrogen bonding, and Dipole-Induced Dipole.
London Dispersion forces exist between every two molecules. They are caused by the movement of electrons between the two molecules, as the movement creates instantaneous, temporary dipoles. It is a very weak force of attraction, and is the only force of attraction between two non-polar molecules.
Dipole-Diople forces exist between two polar molecules. They are caused by the positive dipole of one molecule being attracted to the negative dipole of another. This intermolecular force is stronger than London Dispersion, and exists between two polar molecules.
Hydrogen bonding forces are special cases of dipole-dipole. They are caused by the hydrogen atom of one molecule being attracted to the oxygen, nitrogen or fluorine of another, forming a very strong bond. This intermolecular force is much stronger than both Dipole-Dipole and London Dispersion.
Dipole-Induced Dipole forces exist between one polar and one non-polar molecule. They are caused by an extremely positively or negatively charged molecule attracting another non-polar molecule, despite its even distribution of electrons. This creates an Induced-dipole that is about as weak as London Dispersion.
Three of the four intermolecular forces exist between two Carbonic Acid molecules. These are London Dispersion, as it exists beteween every two molecules, Dipole-Dipole, as Carbonic Acid is a polar molecule with permenant dipoles, and Hydrogen bonding, as Carbonic Acid is a polar molecule which includes both Hydrogen and Oxygen atoms. Dipole-Induced dipole does not exist between two Carbonic Acid molecules, as Carbonic Acid is a polar molecule, and Dipole-Induced dipole requires one polar and one non-polar molecule.
The diagram above shows the forces of attraction between two Carbonic Acid molecules. The red dotted line between the Hydrogen of one molecule and Oxygen of the other represents Dipole-Diople, while the blue line between the same Hydrogen and Oxygen represents Hydrogen bonding.
London Dispersion forces exist between every two molecules. They are caused by the movement of electrons between the two molecules, as the movement creates instantaneous, temporary dipoles. It is a very weak force of attraction, and is the only force of attraction between two non-polar molecules.
Dipole-Diople forces exist between two polar molecules. They are caused by the positive dipole of one molecule being attracted to the negative dipole of another. This intermolecular force is stronger than London Dispersion, and exists between two polar molecules.
Hydrogen bonding forces are special cases of dipole-dipole. They are caused by the hydrogen atom of one molecule being attracted to the oxygen, nitrogen or fluorine of another, forming a very strong bond. This intermolecular force is much stronger than both Dipole-Dipole and London Dispersion.
Dipole-Induced Dipole forces exist between one polar and one non-polar molecule. They are caused by an extremely positively or negatively charged molecule attracting another non-polar molecule, despite its even distribution of electrons. This creates an Induced-dipole that is about as weak as London Dispersion.
The diagram above shows the forces of attraction between two Carbonic Acid molecules. The red dotted line between the Hydrogen of one molecule and Oxygen of the other represents Dipole-Diople, while the blue line between the same Hydrogen and Oxygen represents Hydrogen bonding.
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