1. Changes Matter can change. There are two types of changes:
1) Physical Changes
2) Chemical Changes

2. Physical Changes Physical Change: No new substance is produced.
Physical changes can be reversed.
Involves the movement of atoms, but not changing the:
Number of atoms
Type of atoms
Or how the atoms are bonded (put together).

3. Sugar Cube
Example: Sugar’s shape can change from a sugar cube to single grains of sugar to powdered sugar, but the sugar molecules themselves will remain the same (C6H12O6).

4. Other Examples of Physical Changes!
Crystallizing sugar.
Drying hair.
Slicing a pineapple.
Ironing clothes.
Washing clothes.
Cutting paper
Dissolving iced tea crystals in water.

5. Other physical changes involve a … Change of State!
There are three common states of matter: solid, liquid and gas.
In a change of state atoms/molecules (e.g. Oxygen atoms/water molecules) either move closer together or farther apart due to the addition or removal of heat energy.
This causes a change in the volume and the structure of the substance.
There are 6 changes of state!

6. Water Molecules in Their 3 States

7. Change of State Triangle
SOLID
LIQUID
GAS
Change of State Triangle
melting
freezing
sublimation
condensation
evaporation

8. Heat & Changes of State Heat is added as a substance changes from:
SOLID LIQUID GAS

9. Heat is removed as a substance changes from:
SOLID LIQUID GAS

10. Volume & Changes of State
Volume increases as a substance changes from:
SOLID LIQUID GAS
GAS
LIQUID
SOLID

11. Volume decreases as a substance changes from:
SOLID LIQUID GAS
GAS
LIQUID
SOLID

12. Exception: Water
In the liquid state, water molecules slide past each other in close proximity.
In the solid state, bonds between the water water molecules keep them at a distance from each other.

13. Shape & Changes of State
When matter is solid it usually does not take up as much space as matter in other phases. This makes sense because the molecules are crowded together and do not move away from each other. When they wiggle, they wiggle in place. As a result, they can crowd into a smaller space.

14. In a liquid, matter can take up a bit more space than in a solid
In a liquid, matter can take up a bit more space than in a solid. Because the molecules are free to move around each other, they can spread out more, but they don't go far from each other.

15. The molecules in a gas are moving around like crazy, bouncing everywhere.
They do not have to stay close to one another.
A gas takes up as much space as there is!
However, gas can also be squeezed, or compressed, unlike a liquid or a solid. That is why a deep sea diver can carry enough oxygen for long dives in a tank on his back, and why a small helium tank can inflate dozens of balloons.

16. Video Time: Phases of Matter
Part 1:
Part 2:
Part 3: