1. Chapter 4
States of Matter

2. Key Vocabulary Matter Solid Liquid Viscosity Gas Surface tension
Thermal energy
Temperature
heat
Melting
Freezing
Vaporization
Condensation
Pressure
Buoyant force
Archimedes’ Principle
Density
Pascal’s principle

3. Foldable
Pyramid Fold
Side 1
Solid
Side 2
Liquid
Side 3
Gas

4. What is matter? Anything that has mass and takes up space
Give me some examples of matter

5. States of Matter 3 common states 1 rare state Solid, Liquid, Gas
Plasma- found in stars, lightning, and neon lights
Common in the universe, but uncommon on earth

6. Solids Matter with a definite shape and volume
Particles are moving in vibration patterns that are not seen by the naked eye
Amorphous Solids
Have no definite crystal structure
Examples: rubber, plastic, glass
Crystalline Solids
Particles arranged in repeated 3-D structures called crystals
Examples: Sodium Chloride (cube), diamond (pyramidal)
Other examples: Sugars, sand, snow

7. Connection Amorphous solids are like lemons in a bowl
Crystalline solids are like eggs in a carton

8. What is a Liquid? Has a definite volume, but no definite shape
Takes the shape of any container it is poured into
Particles move freely and allow shape changes

9. Viscosity A liquid’s resistance to flow
High viscosity means that the liquid is very thick and does not run well
Example: molasses
Low viscosity means that the liquid pours easily
Example: water

10. Gases Matter that does not have a definite shape or volume
Particles are farther apart than in any other common state
Can be expanded or compressed
Decreasing the volume (compressing) moves the molecules closer together

11. What is energy? The ability to do work or make a change
We will focus on the ability to make a change now
Ability to do work comes after the holidays
The energy associated with motion is called kinetic energy
The chance that an object might exert energy is potential energy

12. Thermal Energy The total potential and kinetic energy
Depends on the amount of energy in a substance as well as how much of a substance is present

13. Temperature The average kinetic energy of a substance
What is the difference between temperature and thermal energy?

14. Heat
The movement of thermal energy from an object with more kinetic energy to an object with less kinetic energy
When a substance gains heat, it gets warmer
When a substance is cooled, it looses heat
What happens to the particles when they are cooled?

15. Specific Heat
The amount of energy required to raise the temperature of 1g of a substance by 1 degree Celsius

16. Surface Tension The uneven forces acting on the surface of a liquid
Cause the liquid to act as though there is a thin film across the surface
This unseen force allows bugs to float on the surface of a liquid
Believe it or not, you can actually float a needle on water due to surface tension

17. Surface Tension Lab
Question: Can you place more drops of water on the surface of a penny than what will simply fit on the face of the penny?
Hypothesis: If…Then…Because
1 drop at a time place water onto the surface of a penny
When the surface tension breaks, record the number of drops in the data section of your science journal
Repeat 3 times for accuracy

18. State Changes Get out your pyramid foldable
We are going to complete the sides of the pyramid in the next few minutes

19. Melting When an object absorbs thermal energy
The increase in thermal energy causes the substance to change from solid to liquid
Amorphous solids do not change like other solids
They simply get softer and moldable
See figure 10 on page 109

20. Freezing When a substance looses thermal energy
The substance changes from liquid to solid
The temperature at which a substance freezes is known as freezing point

21. Vaporization When a liquid gains thermal energy
Changes from a liquid to a gas
Example: Water boiling into vapor
2 types of vaporization
Boiling- air bubbles form within the liquid and rise to the surface
Evaporation- water at the surface vaporizes, occurs at temperatures below the boiling point

22. Vaporization Demo
I will place one drop of rubbing alcohol on the back of your hand
In your science journal, record your observations for the next 2 minutes
What happened?

23. Condensation
Decrease in thermal energy rearranges the pattern of a gas
Causes the gas to turn into liquid

24. Sublimation
Change from solid form to a gas state without ever becoming a liquid
Example:
At room temperature carbon dioxide is a gas
Dry Ice is the solid form of carbon dioxide
At room temperature, dry ice instantly turns into a gas

25. Pressure
Equal to the force exerted on an object divided by the area over which the force is exerted
Measured in SI Unit:
Force is measured in Newtons (N)
Area is measured in square meters (m2)
Therefore pressure is N/m2 or a unit called the Pascal (Pa)

26. Atmospheric Pressure
The air around you presses on your with a great force, you are just used to the pressure so you don’t feel it
Atmospheric Pressure on earth is 101.3Pa at sea level
This is equal to 101,000 N
Air pressure enables you to drink from a straw
Sucking on the straw eliminates the air in the straw
The air pressure then pushes the liquid up the straw where there is no longer air pressure pushing downward

27. Using a Straw

28. Why don’t you feel the pressure?
The atmosphere pushes with equal force on the outside of your body as the liquid in your body pushes outward
As altitude increases, air pressure decreases
When you rise in an airplane or go up a mountain your ears pop. Why?

29. Buoyant Force
An upward force that presses against an object being pushed downward by air pressure and weight
If the buoyant force is equal to the combined forces, the object will float
Archimedes’ Principle- the buoyant force of an object is equal to the weight of the fluid displaced by the object

30. Density
The density of an object is crucial as to whether it will float
Density is mass divided by the volume
An object that is less dense than the fluid will float
An object that is more dense than the fluid will sink
An object that is equally as dense as the fluid will neither sink nor float, but remain in the same position in the water

31. So how do things float?
If density determines the buoyancy of an object, what two factors must be considered to make an object float?
How do you need to modify these factors to make an object float?

32. Effects of Volume and Temperature
As volume decreases, pressure increases
As Temperature increases, pressure increases also
Bernoulli’s Principle Demo- observe and record in your science journal
What will happen when I place the ping-pong ball on the air current?
What will happen if I tilt the air current?
What will happen if I decrease the air pressure?

33. Chapter Experiment: Build a Boat
Get into your science teams
Question: How does the volume of water displaced by a ship relate to the mass of cargo a ship can carry? Can you create a ship that can float on water and carry cargo?
Hypothesis: If…then…because
Procedures: Write your own procedures for this lab

34. Build-A-Boat Conclusions
A ship can only carry a certain amount of cargo safely
It can carry less high-density cargo than high-density cargo