Four Intermolecular Forces

The structure of a molecule affects how it is able to bond with other molecules and how effective these bonds are. The structure of the molecule itself is held together by the intramolecular forces, which are the internal forces of a molecule, such as the attraction and repulsion of electrons to the protons in the nucleus. The external forces on a molecule, which are called the intermolecular forces, such as electronegativity, help to determine the boiling and melting points of each element. Each of these intermolecular forces differs in strength, but even the strongest one is weaker than the intramolecular forces on a molecule. These melting and boiling points can differ by massive amounts, sometimes going from high positive temperatures …show more content…
The measure of the melting/ boiling point is also a measure of how strong the attraction forces are between atoms or molecules. From the strongest to the weakest, the four types of intermolecular forces used in a molecule that can affect the boiling/melting points of a solid or liquid are London dispersion, dipole-dipole, hydrogen bonds, and ionic bonds. The first and weakest of the intermolecular forces that can affect the boiling/melting points of an element or chemical is the London dispersion force. These forces, proposed by Fritz London, were caused by the fluctuations in the distribution of electrons within both atoms and nonpolar molecules which resulted in temporary instantaneous dipoles, thereby producing attractive forces. The reason that there would be fluctuations in the distribution of electrons can be answered by the constant movement of electrons in the electron cloud around a nucleus, giving the fact that there will more than likely be an asymmetrical pattern in the electrons. When this happens, this new instantaneous dipole can interact with the surrounding electrons, …show more content…
The reason that these bonds are considered the strongest of the intermolecular forces can be shown by Coulomb’s Law and also can be seen though the extremely high boiling temperatures. The attractive force increases as the charge increases, but the distance stays constant, but the attractive force decreases as the charges stay constant, but the distance increases. Since in these ionic compounds, the ions have a strong attraction towards other ions, the boiling temperature increases due to the increases in thermal energy needed to overcome the new intramolecular forces. The fact that these ionic bonds are highly polarized is reflected in extremely high melting points of ionic compounds: for example, the melting point for NaCl is 801

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