1. Phases of Matter Unit Notes

2. HEAT
Heat is one form of ENERGY. It is sometimes called THERMAL ENERGY.
Other forms of energy include:
Light
Sound
Nuclear
Kinetic (energy of motion)
Potential (stored energy)

3. Heat is... A measure of how much kinetic energy matter has
Particles with high heat are moving at a HIGH average speed
Particles with low heat are moving at a LOW average speed

4. Heat Transfer
When we talk about the transfer of heat, we are really talking about transferring KINETIC ENERGY among particles.
Heat always moves from the HOTTER object to the COOLER object.

5. Heat and the Motion of Particles
When we add heat (energy to particles), it does WHAT to their motion?
Heat increases the motion and energy level of the particles
Heating water animation:

6. Phases of Matter GAS is the phase where particles have the most energy
There are three main phases of matter:
Solid
Liquid
Gas
GAS is the phase where particles have the most energy
SOLID is the phase where particles have the least energy

7. Phases of Matter: Solid
Particles have little motion/energy; they are packed/joined together tightly
Particles are very organized
Do NOT move to fit the shape of their container and do not fill the container (they keep their original shape)
It is hard to compress or
change the shape of a solid

8. Phases of Matter: Liquid
Particles have more motion/energy; joined together more loosely
Particles WILL take on the shape of their container but will not fill it entirely
Molecules of a liquid like
to stick together. Liquids
are hard to compress.

9. Phases of Matter: Gases
Particles have a great deal of energy and do not stick together closely; they bounce around a lot!
WILL spread out to fill entire container and fit the shape of the container they are in
Gases=vapor
Gases are easily
compressed

10. Phases of Matter: Plasma
Similar to gases, but made up of ions and electrons of an element
Examples: Northern lights, neon lights, stars
Require a special environment to exist

11. Phases of Matter

12. A phase change is when we change from one state of matter to another
Phase Changes
A phase change is when we change from one state of matter to another
Example: A solid changing to a liquid

13. Names for Phase Changes
Solid to liquid: MELTING
Liquid to gas: VAPORIZATION or BOILING or EVAPORATION
Solid to gas: SUBLIMATION
Gas to liquid: CONDENSATION
Liquid to solid: FREEZING
Gas to solid: DEPOSITION

14. Names for Phase Changes

15. Phase Changes HIGH ENERGY: GAS MEDIUM ENERGY: LIQUID Low energy: solid
ADD
ENERGY
MEDIUM ENERGY: LIQUID
REMOVE
ENERGY
Low energy: solid

16. Phase Changes
To go to a state of matter involving MORE energy, we must ADD energy. We can do this by HEATING the substance.
Examples: If we heat ice (solid), it will turn into water (liquid), and will eventually boil and turn into water vapor (gas)

17. Phase Changes
To go to a state of matter involving LESS energy, we must REMOVE energy. We can do this by COOLING the substance.
Examples: Water vapor (gas) from your hot shower condenses on a cold mirror (liquid). If you leave a window open, it might turn into ice droplets (solid).

18. Phase Change Graphs

19. Phase Change Graphs

20. Phase Change Graphs

21. Check your understanding
What are the three main states of matter?
List these three states of matter from the state with the LEAST amount of energy to the state with the MOST energy
To go from a gas to a liquid, would you need to ADD energy (heat) or RELEASE energy (cool)?

22. Melting Points and Boiling Points are Properties of Matter
We observed that water MELTS/FREEZES at 0 degrees Celsius
We observed that water BOILS/CONDENSES at 100 degrees Celsius
Water’s natural state at room temperature (25 degrees Celsius) is as a LIQUID

23. Different Substances will have Different Boiling Points and Melting PointsZ
Name
Melting Point [°C]
Boiling Point [°C] 1
Hydrogen
-259.1
-252.9 2
Helium
-272.2
-268.9 3
Lithium
180.5
1317 4
Beryllium
1278
2970 5
Boron
2300
2550 6
Carbon
3550
4827 7
Nitrogen
-209.9
-195.8 8
Oxygen
-218.4
-182.9 9
Fluorine
-219.6
-188.1 10
Neon
-248.7
-246.1

24. This results in different natural states at room temperature.
Name a substance that is a liquid at room temperature.
What is the natural state of oxygen at room temperature?
Can you name three substances that are solids as their natural state?
If a substance has a boiling point of -100 degrees Celsius, what is its natural state at room temperature?

25. Check your Understanding
Why are melting points and boiling points considered to be characteristic properties of matter?
What other characteristic properties have we learned about so far this year?