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Glossary
Covalent bond - A bond in which the two atoms involved evenly, or almost evenly share the two electrons in the bond. Often defined with a difference in electronegativity of less than 0.5.
Polar covalent bond - a bond where electrons are shared between two atoms, but the electrons spend more time around one atom than another. Often defined as have an electronegativity between 0,5 and 1.7.
Intermolecular forces - the attraction of molecules through differences in charges at certain locations in the molecule.
London dispersion forces - occur in all molecules, but are the main attractive forces in completely nonpolar molecules. These are caused by electrons moving randomly around the molecule, making it a temporary dipole, attracting another temporary dipole. Larger molecules have larger london dispersion forces due to having more electrons and therefor the ability to polarize more.
Dipole - dipole forces - Attraction between the positive end of one dipole and the negative end of another dipole. Significanlty stronger than London dispersion forces.
Hydrogen bonding - a form of dipole - dipole force, but with hydrogen bonded to fluorine, nitrogen or oxygen. These are significantly stronger than normal dipole - dipole forces, as F, N, and O attract the electron so strongly that it more or less strips it from the hydrogen, causing a much greater polarization in the molecule involved. One good example of this is water and how it has such a high boiling point.
Polar covalent bond - a bond where electrons are shared between two atoms, but the electrons spend more time around one atom than another. Often defined as have an electronegativity between 0,5 and 1.7.
Intermolecular forces - the attraction of molecules through differences in charges at certain locations in the molecule.
London dispersion forces - occur in all molecules, but are the main attractive forces in completely nonpolar molecules. These are caused by electrons moving randomly around the molecule, making it a temporary dipole, attracting another temporary dipole. Larger molecules have larger london dispersion forces due to having more electrons and therefor the ability to polarize more.
Dipole - dipole forces - Attraction between the positive end of one dipole and the negative end of another dipole. Significanlty stronger than London dispersion forces.
Hydrogen bonding - a form of dipole - dipole force, but with hydrogen bonded to fluorine, nitrogen or oxygen. These are significantly stronger than normal dipole - dipole forces, as F, N, and O attract the electron so strongly that it more or less strips it from the hydrogen, causing a much greater polarization in the molecule involved. One good example of this is water and how it has such a high boiling point.