1. Heating and Cooling Curves
From Solid to Gas

2. Phase Changes
A phase changes involves the conversion of a substance from one phase to another. (ex. Solid to liquid)
Phase changes involve a change in energy.
Energy is either released or absorbed during phase changes.
For example , when ice melts energy is absorbed.

3. Phase changes for water

4. Phase changes and particle motion

5. Heating Curve
Freezing is the phase change as a substance changes from a liquid to a solid.
Melting is the phase change as a substance changes from a solid to a liquid.
Condensation is the phase change as a substance changes from a gas to a liquid.
Vaporization is the phase change as a substance changes from a liquid to a gas.

6. Cooling Curve

7. Sample Heating Curve

8. Heat Capacity (C)
The amount of energy needed to raise the temperature of one gram of a substance by 1oC . (units in calories)
Molar heat capacity = the amount of energy needed to raise the temperature of one mole of a substance by 1oC.
Heat of fusion = the amount of energy needed to melt a solid solid liquid
Heat of vaporization = the amount of energy needed to vaporize a liquid liquid gas