- intramolecular bonds exist within a molecule
-ionic, covalent - intermolecular bonds exist between molecules
- the stronger the inter- bonds the higher the BP or MP
- two types of intermolercular bonds: Varder Waals bonds and Hydrogen Bonds
Van der Waals Bonds
- based on electron distribution
- two categories
- 1. Dipole-Dipole bonds
- If a molecule is polar the positive end of one molecule will be attracted to the negative end of another molecule
London Dispersion Forces (LDF)
- LDF is present in all molecules
- creates weakest bonds
- if a substance is non-polar Dipole-Dipole forces don't exist
- Electrons are free to move around and will randomly be grouped on one side of the molecule
- This creates a temporary dipole and can cause a weak bond to form
- the more electrons in the molecule, the stronger the LDF can be
Hydrogen Bonding
- If H is bonded to certain elements (F, O, or N) the bond is highly polar
- This forms a very strong intermolecular mbond
http://www.youtube.com/watch?v=PwveQxLLqD0
http://www.youtube.com/watch?v=90q7xl3ndJ8
BY KRYSTA DEL ROSARIO :)
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