1. Kinetic energy of particles, is proportional to how fast they vibrate
Potential energy of atoms or molecules is proportional to the distance between the particles.
Lower Potential E More Potential E Closer together Further apart

2. Line a: KE ↑
PE constant
Point b: gained so much kinetic energy that the forces keeping the solid distances are overcome
Line c: KE constant
PE ↑
Between points b and d, molecules do not move faster, it will only cause the molecules to move further apart
Line e: KE ↑
Point f: gained so much kinetic energy that the forces keeping the water at liquid distances are overcome.
Line g: KE constant
Along line g any energy added to the molecules will not cause the molecules to move faster, it will only cause the molecules to move further apart

3. Phase Diagrams

4. Critical temperature: temperature above which the vapor can not be liquefied.

5. Critical pressure: pressure required to liquefy AT the critical temperature.

6. Critical point: critical temperature and pressure (water = 374°C and 218 atm).

7. Phase changes by Name

8. Water

9. Carbon dioxide

10. Carbon

11. Sulfur