1. Topic 5
Changing State

4. What is the biggest difference between these two pictures of Edmonton?
Because it is hot in the summer and cold in the winter we already know that temperatures are always changing…

5. Snow.
What happens to the snow when it gets warmer

7. What is happening to the particles when water melts?

8. They gain energy, move faster, and break free of their shape.

10. Liquid to a gas When we add even MORE heat…
The particles move VERY fast and escape all bonds!

11. Different Materials
Different materials expand by different amounts when they are heated.
The amount the temperature rises when thermal energy is added also depends on the substance.
Under identical conditions, materials warm and cool at different rates.

12. Temperature and Thermal Energy
Two substances may have the same amount of thermal energy but have different temperatures.
Scientists use 2 properties to determine how fast something will warm up
Heat Capacity
Specific Heat Capacity

13. Heat Capacity
The amount of thermal energy that warms or cools the object by one degree Celsius.
Describes a particular object
Depends on the mass of the object and the material the object is made of

14. Specific Heat Capacity
The amount of thermal energy that warms or cools one gram of a material by one degree Celsius.
Describes a particular material
Depends on the material the object is made of.

15. Definitions Melt: Turn from solid ice to liquid water
Freeze: Turn from liquid water to ice
Evaporate: turn into invisible water vapour
Condense: Turn back from gas to liquid water
Melting Point: The temperature at which a solid turns into a liquid
Boiling Point: The temperature at which a liquid turns into a gas.

16. What is sublimation?
From solid to gas in one step…

18. Most of the time we go from a solid  liquid  then to a gas.
This happens because we are adding ENERGY
In sublimation we go through this process very fast and go from Solid  Gas