1. Chemical Properties and Changes
How a substance changes when it comes into contact with another substance
Chemical Change
Affects electronic structure of atoms
Changes the arrangement of Atoms
Which atoms are part of a substance
Change Ratios of Atoms

2. Conservation of Matter
Matter is neither created nor destroyed, but only changes forms
No new atoms are created in normal circumstances
This is true for:
Wood Burning
Plants Growing
Other everyday occurrences

3. Nuclear Changes
In very special circumstances, an atom can undergo a change in its nucleus.
Can loose gain some protons or neutrons
Can split into two smaller atoms
Two atoms can combine into one big one
Happens in:
The Sun
Nuclear Power plants
Nuclear Weapons

4. Changes in State A change in state is a physical change Solid – Liquid
Liquid-Gas
State changes occur because of changes in thermal energy.
As thermal energy increases or decreases, particle movement changes, causing a state change

5. Freezing and Melting
When a liquid is cooled, its particle move slower, until it becomes a solid – Freezing or Solidifying
What a solid is heated, the molecules warm up, and are free to move around each other – Melting, Liquefying

6. Vaporization Vaporization - When a liquid turns into a gas
Boiling – Vaporization where the liquid is hot enough to quickly turn into a gas
Occurs at the boiling point
Boiling point increases with increase air pressure.

7. Evaporation
Evaporation – When a liquid turns to gas below the boiling point
Only occurs at the surface
Water molecules collide and hit each other into the gas phase
This takes away some energy from the molecule that stays in the liquid, cooling the liquid.
Sweating keeps you cool

8. Condensation Condensation – When a gas turns back into a liquid
The gas slowly down enough and sticks to something to become liquid

9. Sublimation
Sublimation – When a solid turns immediately into a gas, or a gas turns immediately into a solid
Frost is an example of water vapor forming a solid immediately
Dry Ice, or Solid Carbon Dioxide turns from a solid to a gas immediately

10. Changes in States Review