1. Intermolecular attractions

2. Polarity and Shape
Polar bonds do not necessarily always create a polar molecule.
The shape of the molecule and the polarity of each bond is considered before stating if a molecule is considered POLAR or NON-POLAR

3. Non-polar Molecules
A non-polar molecule is one that the electrons are distributed more symmetrically and thus does not have an abundance of charges at the opposite sides. The charges all cancel out each other.

4. Are the following polar or non-polar MOLECULES?

5. Homework:
Read pages
Take notes on Van der Waals forces (dipole interactions and dispersion forces) and hydrogen bonds. (at least two sentences to explain each.)
Complete questions 32 and 34 on page 253
This assignment is to be hand in tomorrow

6. Intermolecular Forces
Forces binding atoms in a molecule are due to chemical bonding
Intramolecular forces: forces that bond the atoms to each other within the molecule. Vs
Intermolecular forces:

7. Dipole-Dipole Forces Dipole = polar molecule
Dipoles will change their direction so that their oppositely charged ends are near to one another.
The electrostatic attraction between the ends is dipole-dipole force

8. Ion Dipole Forces
The force of attraction between an ion and a polar molecule.
NaCl breaks up because the ion dipole with water is stronger than the attraction of Na+ to Cl-

9. Dispersion Forces
weakest intermolecular force between non polar molecules
It is a temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make the atoms form temporary dipoles

10. Hydrogen Bonding
It is the attractive force between the hydrogen attached to an electronegative atom of one molecule and an electronegative atom of a different molecule.
The molecule involved with hydrogen bonding should have at least one lone pair. More lone pairs= stronger hydrogen bonds.

11. “Like Dissolves Like” Ionic solutes dissolve in polar solvents
(ex: NaCl and H2O)
Non polar solutes dissolve in non polar solvents
(ex: solid I2 and liquid Br2)