1. Polar or Nonpolar

2. Polar What is polar? An uneven distribution of charge.
What makes a bond polar?
The electrons are share unequally

3. Polar vs Nonpolar Molecules
A polar molecule is an molecule with an asymmetric shape or bonds.
Bent and trigonal Pyramidal shaped molecule are asymmetrical
Ex: H
H C Cl ●●
H N H H ●●

4. Polar vs Nonpolar Molecules
A nonpolar molecule will be symmetrical in BOTH shape and bonds.
The bonds should all be to the same element.
Ex: H
H C H
O C O ●●

5. Polar vs Nonpolar Molecules
Are the following molecules polar or nonpolar?
SiF4
SH2
HCN
CS2

6. Intermolecular Forces of Attraction
Intermolecular forces of attractions: Attractions between molecules
These attractions are what hold molecules together to be a solid or a liquid. If the intermolecular force of attraction is very weak you will have a gas.

7. Intermolecular Forces of Attraction
If your molecule is polar you need to see if it has any H-N, H-O or H-F bonds.
If it has any of those bonds it will have hydrogen bonding as its intermolecular force of attraction.
If it does not it will have dipole-dipole.

8. Intermolecular Forces of Attraction
Both hydrogen bonding and dipole-dipole work the same way but hydrogen bonding is significantly stronger.
Polar molecules have dipoles which puts a slight negative (δ-) and positive (δ+) charges on different sides of the molecule.
Lone pairs on the center atom are always δ- if there are no lone pairs then the most electronegative bonded atoms is δ-. The other bonded atoms on the center atom is δ+

9. Intermolecular Forces of Attractionδ+ H
H C Cl ●● δ-
O H H ●● δ+ δ+ δ- δ+ δ+

10. Intermolecular Forces of Attraction
The attraction between the dipoles are what holds the molecules together to be a solid or liquid

11. Intermolecular Forces of Attraction
Nonpolar molecules are help by London dispersion forces
London dispersion forces are very weak and these molecules tend to be gases.
London dispersion forces result from one molecule getting an instantaneous dipole from the random movement of electrons inducing another molecule to also get a dipole.

13. Intermolecular Forces of Attraction
Is the molecule polar?
Yes No
Does it have H-N, H-O, or H-F bonds?
London Dispersion Forces
Yes No
Hydrogen Bonding
Dipole-Dipole

14. What Type or Attraction?
NH3
CH2O
CF4
SBr2