matter & energy

Matter & EnergyChapter 2

Enter

matter – is material such as rocks, water, air with mass and occupying space.

energy – is what makes matter move!Energy is measured in many different units.The metric unit of energy used by scientists is:

What are Matter and Energy?

4.184 joules = 1 calorie

What is Matter? Matter is anything that

has mass and takes up space.

Objects made of matter have physical properties.

Physical properties are characteristics of a substance that can be seen or measured. Color, hardness, and taste are examples of physical properties.

The physical properties of this orange are that it’s round, orange, and soft.

Partner Activity

Take a moment with your partner to name the physical properties of the pictured object.

Check your answers.

Triangular Purple Shiny Hard

Heavy

Pyramid Physical Properties

Mass is the amount of matter in an object.

Mass is measured using a balance in grams.

Mass of an object is always the same.

Measuring Mass

balance

Weight is a measure of the pull of gravity on an object.

Weight of an object can change. Example:

A car that weighs about 2,698 lbs on earth weighs about 450 lbs on the moon due the difference in the force of gravity.

What is Weight?

Measuring Mass by Volume

Volume is the amount of space that an object takes up.

Liquids can be measured using a graduated cylinder (see photo).

Solids can be measured by using a calculation. Length x width x height

Volume

What if the object is an odd shape?

Volume of irregular shapes can be found by placing them in water.

Then, measure the amount of water that is displaced.

Click to watch and learn.

Density is the amount of matter in a certain volume.

The density of an object always stays the same.

Density = mass / volume

Density

Click to watch and learn.

There are 3 states of matter that you are familiar with. Solid Liquid Gas

Visit BBC’s website on the 3 states of mater.

3 States of Matter

Phases of Matter

the phases solid liquid gas plasma

depend on how tightly bound the atoms and/or molecules are

As temperature increases, these bonds are loosened:

Temperature vs. Heat

Temperature is the average kinetic energy.

Heat (thermal energy) is the total kinetic energy.

lower T higher T

same T

less heat more heat

Temperature Scales

Solid Has a shape and a

definite volume. Feels firm when

you touch it. The particles are

packed closely together.

Examples

rock

helmet

candy

Liquid

Has a definite volume but no definite shape.

The particles of a liquid move more freely.

Can change shape. Examples

ocean

soup

soda

Gas

Gas does not have a definite shape or volume.

The particles are freer to move around and move the fastest.

Gas flows and takes the shape of the container.

Changes Between States of Matter

All substances can change states.

Liquids can freeze. Freezing changes a liquid to a solid.

Changes Between States of Matter

Melting changes a solid to a liquid.

Boiling changes a substance from a liquid to a gas.

What is a Solution?

A solution is a mixture in which different kind of matter mixed even with each other.

Example: Adding sugar to water A solution can only be made when one

substance dissolves. Click to visit the mixture lab.

Physical Changes Physical changes occur when matter

changes its property but not its chemical nature.

Physical property changes are any change in size, shape or state of a substance. Sugar can undergo many

physical changes. Even though each form is different, they are still sugar.

Physical Change

Chemical Changes

Burning is an example of a chemical change.

Light and warmth are released. Smoke, ash, and hot gases are produced.

Chemical changes are changes matter undergoes when it becomes new or different matter.

To identify a chemical change look for signs such as color change, bubbling and fizzing, light production, smoke, and presence of heat.

Chemical Changes

What is Energy?

Energy is the ability to do work.

Energy is the ability to cause changes in matter.

Light, sound, heat, and electricity are forms of energy.

Three categories of energy are:1. Kinetic Energy2.Potential Energy3.Radiant Energy

kinetic energy of motion

potential stored energy

radiant energy transported by light

Energy can change from one form to another.

Three Basic Types of Energy

Amount of kinetic energy of a moving object= 1/2 mv2

[if mass (m) is in kg & velocity (v) is in m/s, energy is in joules]

On the microscopic level the average kinetic energy of the particles

within a substance is called the temperature. it is dominated by the velocities of the particles.

Kinetic Energy

energy is stored in matter itself this mass-energy is what would be released if

an amount of mass, m, were converted into energy

Potential Energy

E = mcE = mc22

[ c = 3 x 108 m/s is the speed of light; m is in kg, then E is in joules]

gravitational potential energy is the energy which an object stores due to its ability to fall

It depends on: the object’s mass (m) the strength of gravity (g) the distance which it falls (d)

Potential Energy

m

d

g

Energy can be neither created nor destroyed. It merely changes its form or is exchanged

between objects. This principle (or law) is fundamental to science. The total energy content of the Universe was

determined in the Big Bang and remains the same today.

Conservation of Energy

Energy Sources

It comes from many different sources. Solar Chemical Water Nuclear Wind Natural Gas Fossil Fuels

Solar Energy

This is energy that comes from the sun.

All living things depend on this energy.

Does not damage the environment.

Can be used for heat and electricity.

Click to watch and learn.

Chemical Energy

Energy stored in a substance and released during a chemical reaction such as burning wood, coal, or oil.

Hydroelectric (Water) Energy Energy the comes

from moving water. Dams are built to

store water and generate electricity.

Hydroelectric power is produced as water passes through a dam, and into a river below. The more water that passes through a dam, the more energy is produced.

Nuclear Energy Energy that

comes from splitting atoms of radioactive materials, such as uranium

Used to produce electricity.

Wind Energy Wind is air moving

around. Wind is used to

generate electricity.

Windmills are used to create this electricity.

Safe for the environment.

Fossil Fuels

Fuels (coal, oil, natural gas, etc.) that result from the compression of ancient plant and animal life formed over millions of years.

Fossil fuels are oil, coal, natural gas, and uranium.

This means that this type of energy cannot be made again.

An energy source that we are using up and cannot recreate in a short period of time.

Nonrenewable Energy Sources: nuclear oil coal natural gas

Nonrenewable Energy

This type of energy can be replenished. An energy source that we can use over and

over again. Renewable Energy Sources:

solar wind water

Renewable Energy

Electric Energy

Electric energy is the energy produced by the movement of electrons.

When an object gains or loses electrons, it has an electric charge.

When an object has a charge, it attracts objects with the opposite charge.

This is called an electrical force. An electric current is the flow of electrons

from negatively charged objects to positively charged objects.

Electric Energy

An electric current is the flow of electrons. To light a light bulb or run a computer, you

need a continuous electric current. A battery or generator can be the source of

electrons.

Electric Current

Electric Energy

Conductors of electricity are materials that carry electrons easily from one terminal to another.

A conductor is used in the wire that makes an electric circuit. An electric circuit is any path in which electrons can flow.