Van Der Waals And Permanent Dipole Forces Essay, Research Paper

Van der Waals forces Act between all atoms and molecules. Van der Waals forces are caused by the formation of temporary

dipoles due to constant movement of electrons. The size of the force depends on the size of the molecule. In a

large molecule, there are more electrons therefore the Van der Waals forces

between large molecules are stronger than between smaller

molecules. Permanent dipole forces Occur between molecules with permanent dipoles. Permanent dipoles are formed when there is a large difference

in electronegativity between two atoms bonded together in a covalent bond. This

causes the shared pair of electrons to be shared unequally. They are pulled

towards the more electronegative atom. e.g. H—F has a permanent dipole. The shared pair of electrons

are shared unequally and are pulled towards the electronegative F

atom.