1. Chapter 2
States of Matter

2. Matter Anything that takes up space and has mass
Composed of tiny particles
What are they called????????
Three states of matter:
Solid, liquid, gas
Plasma is the fourth state
Occurs only at very high temperatures and is not common on Earth

3. Movement of Particles Atoms are always moving in matter
They move faster when they have more kinetic energy (energy of movement) and slower when they have less kinetic energy
More heat = More energy

4. Solids
Matter with definite shape and volume because particles are packed closely together and merely vibrate in place
Very little kinetic energy in particles
So they move very slowly
Particles of solids arranged in one of 2 ways:
Crystals - arranged in repeating, 3-D patterns
Amorphous - have random arrangement

5. Liquids Matter with a definite volume but no definite shape
Particles move more freely than those of a solid
Particles have more kinetic energy than particles in solid
So they are moving faster than in a solid
Viscosity is a liquids resistance to flow
Increases when particles are more strongly attracted to each other
Surface Tension is the tendency of molecules of a liquid to stick together
Due to uneven forces acting on particles

6. Gasses Matter that does not have a definite shape or volume
Diffusion is the movement of particles from an area of high concentration to an area of low concentration
If you spray cologne, the smell will eventually spread out.
Gas particles spread out evenly and as far apart as possible
They will fill a container.
Most kinetic energy
So they are moving the fastest

7. Section 1 Review
Define matter in your own words and give three things containing matter.
Describe the movement of particles within solids, liquids, and gases.
Why do liquids flow?
A scientist places 25 mL of a yellow substance into a 50-mL container. The substance quickly fills the entire container. In which state of matter is the substance? Why?
Two of the three common states of matter can be grouped together. Which two states share a similar property? Explain.

8. Changes of State Particles are in constant motion
Amount of movement depends on their kinetic energy (energy of movement)
Thermal energy is the total energy of all the particles in a sample of matter
Temperature is the average kinetic energy of particles in a substance
Heat is the movement of thermal energy from a substance with a higher temperature to one with a lower temperature

10. Changes of State
Specific Heat is the amount of heat needed to raise the temperature of 1 g of a substance 1°C
For example, the specific heat of water is equal to one calorie

11. Changes of State
Matter can change states as energy is absorbed or released
A change from the solid to the liquid state is called melting
Is energy absorbed or released?
What happens to the particles?
A change from the liquid to the solid state is called freezing?

12. Changes of State A change from liquid to gas is called vaporization
Boiling is vaporization which occurs below the liquid’s surface at its boiling point
Evaporation is vaporization which occurs at the surface of a liquid
Molecules must be at or near the surface at the right speed to evaporate
What about energy?
What about particles?

13. Changes of State Condensation is a change from a gas to a liquid
What about energy?
What about particles?
During sublimation, the surface particles of a solid gain enough energy to become a gas.

14. Pressure
Pressure equals the force exerted on a surface divided by the total area over which the force is exerted
Pressure(P) = Force(F) / Area(A)
If force increases over an area, the pressure increases
If force over an area decreases, the pressure decreases

15. Section 2 Review
How are thermal energy and temperature similar? How are they different?
How does a change in thermal energy cause matter to change from one state to another?
During which three changes of state is energy absorbed?
What are two types of vaporization?
Do particles of gold move faster in the liquid or the solid state? Liquid or gas?
How can the temperature of a substance remain the same even if the substance is absorbing thermal energy?

16. Pressure
Atmospheric pressure is the air that presses down on the Earth with force
Pressure can be balanced as the pressure pushing down equals the pressure pushing up
As altitude increases, air pressure decreases
That’s why it’s colder at higher altitudes

17. Gas Pressure in Containers
Gas pressures in a closed container changes with volume and temperature changes
Decreasing volume increases pressure
Increasing volume decreases pressure
Increasing temperature increases pressure
Decreasing temperature decreases pressure

18. Boyle’s Law
At a constant temperature, pressure times volume is a constant
They are inversely related (as one goes up, the other goes down)

19. Charles and Gay-Lussac’s Law
At a constant pressure, Volume = a constant times temperature
Volume and temperature are directly proportional (as one goes up, the other goes up)

20. The Ideal Gas Law Charles’ and Boyle’s Law Combined
pV=nRT (n and R are constants)
Pressure x Volume is proportional to Temperature
pV~T

21. Buoyant Force An upward force on an object immersed in a fluid
Archimedes’ principle states that the buoyant force on an object is equal to the weight of the fluid displaced by the object
If a boat displaces 10,000 N of water, then the buoyant force upward from the water will be 10,000 N (it will seem 10,000 N lighter)

22. Density Density is mass divided by volume
D = M/V
It’s all about the love
An object will float in a fluid that is denser than the object
An object with the same density as the fluid will stay the same level in the fluid
An object will sink in a fluid that is less dense than the object

23. Density and States of Matter
Which is more dense: ice, liquid water, or water vapor?
As particles of water get more energy (from heat), they move faster and spread apart more.
As particles move faster, they spread apart and become less dense.
Where is the air the least dense? Why?
The air particles are farther apart at high altitudes and are less dense (due to pull of gravity)

24. Pascal’s Principle
When a force is applied to a confined fluid, an increase in pressure is transmitted equally to all parts of the fluid
Hydraulic systems allow people to lift heavy objects with relatively little force
When squeezed, liquids will be pushed out of a force pump, a closed container with a hole in it.

25. Section 3 Review
What happens to pressure as the force exerted on a given area increases?
How does atmospheric pressure change as altitude increases? How does density change?
An object floats in a fluid. What do you know about the buoyant force on the object? How does the density of the object compare with the density of the fluid?
Why does wood float in water?
Which is more dense: the crust of the Earth or the oceans?
What would the Earth look like if the oceans were more dense than the crust?
All of the air is removed from a sealed metal can. After the air has been removed, the can looks as if it were crushed. Why?