1. II. Forces of Attraction

2. Water
The only substance we are familiar with as a solid, liquid and gas.

3. A. Molecular Forces Intramolecular Ionic Bonds Covalent Bonds
Metallic Bonds
Within Particles
Intermolecular
Dispersion Forces
Dipole-dipole Forces
Hydrogen Bonds
Between Particles

4. B. Dispersion Forces Creation of temporary dipoles
Electron clouds in close contact repel
Temporary dipoles (positive and negative regions)
Attraction increases with particle size
Also called London or Van der Waals forces

5. C. Dipole-dipole forces
Permanent dipoles
Oppositely charged regions of polar molecules
Adjacent molecules orient to each other

6. D. Hydrogen Bonds Specialized type of dipole-dipole force
H + O, F or N
H2O – most famous example
Responsible for water’s unique properties
Click for animation on all IM forces
Web or Real video

7. III. Liquids and Solids Liquids Fixed volume
Variable shape – adjusts to container
Practically incompressible
Fluid – can flow and diffuse

8. Hydraulics

9. B. Viscosity Resistance of a liquid to flow
Type of intermolecular forces
Size and shape of particles
Temperature

10. Multi-viscosity motor oil

11. Surface tension

12. Surfactants – lower surface tension – basis of detergents

13. Cohesion

14. Adhesion
Water (L) and mercury (R) Adhesion > cohesion; cohesion > adhesion

15. Capillary Action (adhesion)

16. III. Solids
Firewalk, Agia Eleni, Greece
Click on picture

17. A. Structure Particles in constant motion Strong attractive forces
Vibrations around fixed locations
More order than in fluids

18. B. Density Most solids will sink in their own liquids (more dense)
Main exception – H2O
Rigid crystal structure takes more space

19. C. Crystalline Solids Orderly, geometric structure
Crystal lattice – location of particles on a framework
Unit cell – smallest intact part of a whole crystal
(You will not be tested on the unit cell types, p. 421)

20. 4. Categories of crystalline solids
Atomic – group 18 at low temps
Molecular – covalent single bonds
Covalent network – repeating structure; diamond, quartz, etc.
Ionic – metal + nonmetal
Metallic

21. 5. Amorphous solids No regular, repeating pattern
Often product of rapid cooling
Glass, rubber, plastic

22. IV. Phase Changes

23. A. Phase Changes Requiring Energy

24. Key Terms/Points:
Melting point – exact for crystalline solids, approximate for amorphous solids
Aluminum – O C Cocoa butter – OC

25. 2. Vaporization – change from liquid to gas
Evaporation – any temperature, surface only
Vapor Pressure – pressure of a vapor on top of a liquid
Boiling Point – VP inside a liquid equals external VP.

27. 3. Sublimation
Direct transition from solid to gas

28. B. Phase Changes Releasing Energy
1. Freezing – releases energy to a point where bonds can re-form.

29. 2. Condensation
Change from gas to liquid

30. 3. Deposition
Change from gas to solid

31. C. Phase Diagram
A graph of pressure vs. temperature that shows which a phase a substance exists in under different conditions of temperature and pressure.

33. Pressure Cooker & Autoclave
Raises temperature by raising pressure

35. Carbon Dioxide tank cars

36. Phase Diagram for Carbon

37. Diamond Making Machine