Chapter 16

States of Matter

Chapter 16: State of Matter

Section 1:

Kinetic Theory

You will learn how to… Explain the kinetic theory of matter Describe particle movement in the 4 states of matter Explain particle behavior at the melting and boiling

points

This is important because:

You can use energy that is lost or gained when a substance changes from one state to another.

What is matter?

Matter- is anything that has mass and occupies space

Four States of Matter

Solid

Liquid

Gas

Plasma

Kinetic Theory Kinetic Theory- an explanation of how

particles in matter behave

3 Assumptions of the Kinetic Theory

1. All matter is composed of small particles (atoms,

molecules, and ions)

2. These particles are in CONSTANT, random

motion.

3. These particles are colliding with each other

and the walls of their container.

Thermal Energy Thermal Energy- the TOTAL energy of a

material’s particles.

Thermal Energy = kinetic energy (vibrations)

+ the potential energy (movement within and between the particles.)

Question

What do you think would happen to the speed of a substance’s particles, IF the TEMPERATURE was decreased ( )?

Answer……

When the temperature of a substance DECREASES ( ), the particles will have

LESS thermal energy and will vibrate

Question

What will happen to the speed of the particles IF you INCREASE ( ) the temperature?

Answer……

When the temperature of a substance INCREASES ( ), the particles will have MORE thermal energy and will vibrate

Average Kinetic Energy

Temperature is used to explain how HOT or COLD an object is.

In science, temperature means the average kinetic energy in the substance, or how FAST the particles are moving.

Average Kinetic EnergyLet’s Look….

Temperature 0C Speed of Particles

Average Kinetic Energy

HOT 1000C FAST HIGH

COLD 00C SLOW LOW

ABOLUTE ZERO

-273.150C VERY SLOW

VERY

LOW

Question?

TRUE OR FALSE

The molecules of frozen water have a HIGHER average kinetic energy than the

molecules of boiling water.

Answer……

The molecules of frozen water have a LOWER average kinetic energy than the molecules of

boiling water. The molecules of frozen water are moving slow so the average kinetic energy is low.

States Of Matter

Solid Liquid Gas

Plasma

States of Matter

Solid State Definite Shape

Definite Volume The attraction between

the particles is STRONG

The particles are held CLOSE together

States of Matter

Liquid State NO definite Shape Definite Volume

The attraction between the particles is NOT

TOO strong The particles FLOW

past each other

States of Matter

Gas State NO definite Shape

NO definite Volume The attraction between

the particles is VERY WEAK

The particles are very FAR apart

States of Matter

Plasma State NO definite Shape

NO definite Volume The attraction between

the particles is EXTREMELY weak

The particles are very FAR apart

Plasma is matter consisting of positively and negatively charged particles.

Plasma exists where the temperature is EXTREMELY HIGH (ex. lightning bolts, sun, neon and fluorescent tubes)

States of Matter

Solid Liquid Gas

ADD HEAT

REMOVE HEAT

This graph shows the heating curve of water. At A and C the water is increasing in kinetic energy. At B and D the added energy is used to overcome the bonds between the particles.

Question?Can you find 3

states of matter in this

picture?

Melting Point

Melting Point- the temperature at which a solid begins to liquefy

SOLID LIQUID

Ex. Ice Water

Heat of Fusion- amount of energy needed to change a substance from solid phase to a liquid phase

Boiling PointBoiling Point- the temperature at which the pressure of

the vapor in the liquid equals the pressure of the vapor on the surface of the liquid

LIQUID GAS

Ex. Water Water Vapor

Heat of vaporization- the amount of energy needed to change a liquid at its boiling point to a gas

Thermal Expansion

Thermal expansion- an increase in the size of the substance when the temperature is increased

Ex. Concrete walkwaysConcrete absorbs heat and expands, so some concrete walkways have expansion joints (gaps) to prevent it from cracking.

Contraction

Contraction- a decrease in the size of the substance when the temperature decreases (shrinks)

Ex. The liquid in a thermometer contracts (shrinks) as the temperature cools.

Expansion and ContractionHeating the air in a hot air balloon

causes the distance between the particles in the air to

expand. The air in the hot air balloon becomes less dense,

and it rises!

Question: What happens if the air inside of the balloon is cooled?

So Tell Me….

When the temperature INCREAES ( ), the particles of solids, liquids and gases will

expand.

When the temperature DECREAES ( ), the particles of solids, liquids, and gases will

contract.

Strange Behavior of Water

Question: What happens to a bottle of water when you put it in the freezer?

Water is the EXCEPTION!

Water expands when the temperature decreases.

Strange Behavior of WaterWater is an EXCEPTION to the thermal expansion

rule!

Water molecules are partially positive and partially negative, so when water freezes the molecules

orient themselves according to charge, and empty spaces occur in the structure.

Water EXPANDS when the temperature decreases ( )

Water CONTRACTS when the temperature increases ( )

Chapter 16: Section 2Properties of Fluids

You will learn about……… Properties of fluids

Viscosity Density Buoyancy

Definition of FLUID

Fluid- materials that flow. GASES and LIQUIDS are fluids.

Water = LIQUID

Water Vapor = GAS

ViscosityViscosity- a fluids RESISTANCE to flow

Ability to Flow Resistance Level Viscosity Level Example

Flows Fast Little to no resistance LOW Water

Flows Slow A lot of resistance HIGH Syrup

Some fluids move slowly. They have a high viscosity.

Syrup pours slowly.

It is very viscous.

Syrup flows SLOW, so it has a HIGH viscosity level.

Viscosity

Question: What happens to the viscosity of syrup after heating it?

Viscosity

Glue is also viscous.

Viscosity

Water pours quickly.

Some fluids move quickly. They have a low viscosity.

It is less viscous.

Density Density- mass per

unit volume of a material

Density of water 1 g/ml

The density of the object is LESS than water (1g/ml). FLOATS

The density of the object is MORE than water (1g/ml). SINKS

Density Column

True or False

Oil is more dense than alcohol and less dense than

water.

Water Density = 1g/mL

Oil

Density = .96 g/mL

Alcohol

Density = .75 g/mL

Answer….

Oil is more dense than alcohol and less dense than

water.Water Density = 1g/mL

Oil

Density = .96 g/mL

Alcohol

Density = .75 g/mL

Buoyancy

Buoyancy is the UPWARD force of a fluid on an object.

Buoyant Force

Buoyancy

Another example of buoyancy is a hot air balloon. The air, which is a fluid, buoys the balloon.

Buoyant Force

Buoyancy

Buoyant Force

Some organisms use buoyancy to move.

Activity Time

Chapter 16: States of Matter

Section 3

Behavior of Gases

What will you learn… How a gas exerts pressure on its container How a gas is affected when pressure,

temperature, or volume is changed

This is important because:

It helps explain and predict the behavior of gases. This is useful because we live in a sea of air.

Remember….

The atmosphere is a FLUID because it is composed of gases.

Particle Collision The gas particles in the air are constantly

colliding with anything in their path. The collisions of these particles in the air

result in atmospheric pressure.

Did you know… Balloons and bicycle tires remain inflated

because of collisions the air particles have with the walls of their container.

These collection of forces, caused by the collisions of the particles pushes the walls of the container outward.

Let’s Look…

What if…..

What would happen if more air was pumped into the balloon?

Answer..

If more air was pumped into a balloon, the number of air particles would INCREASE and the balloon would expand.

Pressure VS Volume

Question: If all of the air was collected from the gym and placed in a closet, what would

happen to the pressure in the closet?

Pressure VS Volume

Answer: If you squeeze gas into a smaller space, the gas particles will strike the walls of the container more often….causing an

INCREASE in pressure.

Pressure VS Volume

Question: If all of the air was collected from a closet and placed in the gym, what would happen to the pressure inside of the gym?

Pressure VS Volume

Answer: If you give the gas particles more space, they will hit the walls LESS often…

gas pressure will be REDUCED.

Boyle’s Gas LawBoyle’s Gas Law states:

DECREASE ( )in volume of container

INCREASE ( ) in pressure….

INCREASE ( ) in volume of container DECREASE ( ) in pressure.

Temperature is CONSTANT

Boyle’s Gas Law

Boyle’s Gas Law

(Initial Pressure X Initial Volume) = (Final Pressure X Final Volume)

P1V1 = P2V2

Temperature is Constant!

Pressure VS Temperature

Question: What do you think will happen if you increase the temperature of a pressurized

spray canister?

Ex. Hair spray

Pressure VS Temperature

Answer: If you increase the temperature of a pressurized spray canister (Hair spray), the

canister would EXPLODE due to the INCEASED pressure caused by the rapidly

moving gas particles against its walls.

Question?

How are hot air balloons inflated?

Answer….Hot air balloons are

inflated because heat causes the gases to expand. The gas particles in hot air are father apart than in the cool air, the hot air is less dense than the cool air so it rises!

Charles’s Gas Law

Charles’s Gas Law states:

Temperature DECREASES ( ) VOLUME DECREASES ( )

Temperature INCREASES ( ) VOLUME INCREASES ( )

Pressure is CONSTANT

Charles’s Gas Law

Charles’s Gas LawT1 / V1 = T2 / V2

1 = Initial or Start2 = Final

Video Time