1. Grab a small whiteboard
Drill
Grab a small whiteboard
What is the formal charge on each atom in the following structure?
What is the overall charge on the molecule?

2. Drill – Part 2
What is the Lewis structure of PO4-3?

3. Check HW and Review of some concepts IMF Lab More IMF practice
Agenda
Registration Stuff
Check HW and Review of some concepts
IMF Lab
More IMF practice

4. Let’s Discuss…
What is the difference between intramolecular and intermolecular forces?

5. Intra – within a molecule
Inter – exist between molecules

6. Ionic Polar covalent Nonpolar covalent
When referring to intramolecular forces, which one of these is the strongest?
Ionic
Polar covalent
Nonpolar covalent

7. 3 Types of Intermolecular Forces (IMF)
London Dispersion (weakest)
Dipole-dipole
Hydrogen

8. Chart = Important

9. T or F?
All molecules have dipole-dipole interactions?

10. False – all compounds have London Dispersion forces
NOTE: The more electrons a molecule has, the stronger the Dispersion forces

11. The stronger the intermolecular forces of attraction, the more energy is required to break those forces.

12. What type of IMF is involved?
SiCl4
1. Dispersion
2. Dipole-Dipole
3. Hydrogen

13. Dispersion forces
Nonpolar molecule

14. What type of IMF is involved
AsCl3 and H2S bond together?

15. Both are polar molecules – so dipole

16. Lab Time!

17. Molecular Weight
Mass of a molecule
As the weight increases, IMF increases

18. Surface Tension
The stronger the intermolecular forces in the liquid, the greater the surface tension

19. Strong odor indicates weak IMF because of lower vapor pressure
compound can have an odor only when its vapor pressure is sufficient to supply a noticeable amount of vapor to the nose. If intermolecular forces are strong, vapor pressure is low, because molecules have less free energy in the solid or liquid than as vapor.

20. Evaporation Rate
The stronger the intermolecular forces in a liquid, the slower the evaporation rate because the molecules are held together by stronger attractions.
You should note that a liquid doesn't necessarily have to reach boiling point before evaporation can occur. Evaporation takes place all the time. 

21. Safety Goggles! Place bookbags on table/away from lab stations
You will have 4 minutes at each station
Make sure cap is back on the bottle ASAP!!

22. When you are done… Answer analysis questions Place lab in the bin
Start IMF Practice – You will get an answer key
Use your own notes to help you! 
Start Review Packet

23. Next Week
Monday: Finish IMF and Review
Wednesday: Unit 3 Test