SG 2.4 Flashcards
Describe London dispersion bonds.
A temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make the atoms form temporary dipoles.
Describe Dipole-dipole bonds.
Occur when the partial charges formed within one molecule are attracted to an opposite partial charge in a nearby molecule.
Describe hydrogen bonds.
An attraction between two atoms that already participate in other chemical bonds. One of the atoms is hydrogen, while the other may be any electronegative atom, such as oxygen, chlorine, or fluorine. Hydrogen bonds may form between atoms within a molecule or between two separate molecules.
Ranking intermolecular attractions from weakest to strongest and vice versa in solution.
The intermolecular forces ranked from weakest to strongest are London dispersion forces, dipole-induced dipole, dipole-dipole interactions, and hydrogen bonding.
Determine whether a molecule is polar or nonpolar based on its structure.
If the arrangement is symmetrical and the arrows are of equal length, the molecule is nonpolar. If the arrangement is asymmetrical and the arrows are of different lengths, the molecule is polar.
How to tell if a particular molecule is a hydrogen bond based on its structure?
Any molecule which has a hydrogen atom attached directly to an oxygen or a nitrogen is capable of hydrogen bonding. Hydrogen bonds also occur when hydrogen is bonded to fluorine, but the HF group does not appear in other molecules. (H-O)
How to tell if a particular molecule is a dipole-dipole bond based on its structure?
When there are attractive forces between the positive end of one polar molecule and the negative end of another polar molecule.
How to tell if a particular molecule is a London dispersion bond based on its structure?
Look to see if the molecule is non-polar and symmetrical. Example - Methane CH4
Determine whether a molecule will be soluble in water based on its structure.
It determines on its polarity. Water is a polar molecule and dissolves the polar compounds in it. In other words, we can say that polar compounds are soluble in water and the non-polar compounds are insoluble in water.
