1. Heat of Fusion The 3 phases of matter show the different states of motion found in matter. The phase of matter depends on 2 factors, the temperature and the intermolecular forces strength

2. How do the particles move? The 3 phases of matter show the different states of motion found in matter. The phase of matter depends on 2 factors, the temperature and the intermolecular forces strength Transitional Energy- when particles freely move around Vibrational Energy- stays in one place and moves.

3. Review of phases Solids- locked together, in crystal lattice. Vibrate but do not move around – They do not have Translation energy. Particles have strong attractions for each other. Definite volume and shape Liquids- some attraction, but free to move around, no def shape, but def volume. Have translation energy. Gases- small particles, extremely weak forces of attraction for each other. Spread out in no pattern into empty space, can be expanded or compressed.

4. Phase Change Is a physical change in how the particles in a substance move and are arranged. It does not cause one substance to change into another. These phase changes have specific names.

5. Melting- Solid turns into a liquid Particles of a solid move away from each other and their structure is broken up. To make this happen, energy is needed to over come attractions. The energy is used to break the structure apart and move particles away from each other. Temperature- the measure of the average kinetic energy of a substance ; a measure of the vibrations in a substance.

6. Since the energy used for melting pulls particles apart this is potential energy, not kinetic, hence no increase in vibrations and no increase in KE. The temperature REMAINS CONSTANT during a phase change. PE- Stored energy KE- moving Energy

7. Boiling- When a liquid turns into a gas, particles go from attracted and close to free to go anywhere Increasing PE

8. Freezing & Condensation Freezing- When a liquid changes to a solid, where particles attract, energy is lost. Condensation- gas to liquid, energy is lost

9. Sublimation & Deposition Sublimation- when a solid directly turns to a gas. There is NO liquid faze Ex: CO2(s)  CO2(g)

10. Heat of Fusion Energy required to melt one gram of a substance at it’s melting point. Each substance has it’s own UNIQUE Heat of fusion Hf water  334j/g Q=mHf This same equation is also used to show heat released when freezing. Freeze or melt=Hf

11. Heat of Vaporization Energy needed to boil 1 gram of a liquid at its boiling point to 1 gram of gas. Or energy released when a gas condenses Water Hv=2260 j/g Q=mHv Boiling and condensing= Hv

12. Temperature- the average kinetic energy of the particles in a substance The lowest possible temp occurs when molecular motion (vibration) stops This temp is called absolute zero (-273C = -418 F)

13. Kelvin scale sets absolute zero to zero So the kelvin scale and the C scale are off by 273 units. K= C+273 C=K-273 **Kelvin cannot have negavite values

14. Melting point of water = C=0C K=273K Boiling point of water= C=100C K=373K All MP and BP on table S are in Kelvin. If given C in a question you must convert to K than use table S

15. The MP is the temp where solid phase changes to liquid phase of substance. Each pure substance has its own unique MP which is used to identify an unknown substance.

16. STP= Standard Temp & Pressure Is the set of conditions which equalizes the results of chemical experiment The Standard Temp=OC or 273K The Standard Gas=101.3kPa or 1 atm or 760 torr ** This info is found in table A

17. If both MP & BP are above STP it is a solid If only BP is above STP it is a Liquid If both MP & BP are below STP it is a gas.

18. Evaporation Is a surface event where some liquid particles gain enough energy to enter the gas phase

19. Boiling Occurs when every liquid particle has enough energy to go to a gas

20. Vapor Pressure Above the surface of a liquid the gas particles of the lquid which have evaporated accumulates. This vapor exerts a pressure on its surroundings This is called the vapor pressure

21. Atmosphere or air pressure The force air exerts on its surroundings. Air pressure forces the liquid particles to stay as a liquid. The vapor pressure pushes up on the air pressure trying to become a gas. When air pressure is greater than vapor pressure, evaporation occurs.

22. Boiling Occurs when a liquid’s vapor pressure equals the atmospheric pressure. Normal boiling point- occurs when a substances vapor pressure equals standard pressure (101.3kPa, 706 torr, 1atm).

23. If the atmospheric pressure is below standard, a substance’s boiling point is lower than normal.