The Nature of Matter

Sunshine Standards and GLE’s

• Benchmark SC.A.1.2.2: The student knows that common materials (e.g., water) can be changed from one state to another by heating and cooling.

• Grade Level Expectations– Third: The student understands that physical changes

in the states of matter can be produced by heating and cooling.

– Fourth: The student understands that heating or cooling of matter will speed up or slow down, respectively, the motion of small particles within the matter and that this is what causes a phase change.

– Fifth: The student knows that matter is conserved during heating and cooling.

SOLID LIQUID GAS PLASMA

Solids are usually hard because

their molecules have been

packed together. The closer the molecules are, the harder the solid is. Solids hold their own

shape.

Liquids will fill up the shape of a

container. Water is a liquid. Your blood is a liquid. Liquids are an in-between state of matter. They can

be found in between the solid and gas states.

Gases can fill a container of any size or shape.

gases are really spread out and the atoms and

molecules are full of energy. They

are bouncing around

constantly.

Plasmas are made up of free electrons and

ions of the element. You see plasma when you

look at stars. Stars are big balls of gases at really

high temperatures.

A closer look at plasmaPlasma is not a gas, liquid, or solid - it is the fourth state of matter. Plasma often behaves like a gas, except that it conducts electricity and is affected by magnetic fields. On an astronomical scale, plasma is common. The Sun is composed of plasma, fire is plasma, fluorescent and neon lights contain plasma. At least 85% of the universe is made up of plasma.

• Physical changes between the states of matter can be produced by heating and cooling.

Let’s take another look at the states of matter

http://www.explorelearning.com/index.cfm?method=cResource.dspDetail&ResourceID=30

Description of Phase Change

Term for Phase Change

Heat Movement During Phase Change

Solid to liquid MeltingHeat goes into the solid as it melts.

Liquid to solid FreezingHeat leaves the liquid as it freezes.

Liquid to gasVaporization, which includes boiling and evaporation

Heat goes into the liquid as it vaporizes.

Gas to liquid CondensationHeat leaves the gas as it condenses.

Solid to gas SublimationHeat goes into the solid as it sublimates.

• Let’s take a closer look with water.

When water is frozen it is ice, a

solid. (0°C)

When ice is melting, it is heating up. Melted

ice is a liquid.

Once the ice has melted you have

liquid water. (1-99°C)

If you heat the water more it becomes

steam, a gas. (0°C)

TEMPERATURELOW HIGH

• Lab 1: Melting Crayon– A crayon is melted and the results are observed– This activity may be conducted in various ways

• Crayon shavings can be melted using aluminum foil and a tea light

• A whole crayon can be melted using a pan and a Bunsen burner or a portable electric burner

– By applying heat, the crayon goes from a solid to a liquid. Once the heat is removed or cooling is applied it returns to its original state, but not to its original shape.

• Lab 2: Identify that state of matter! – Students must identify the state of matter in the

mystery object– This activity could also be done in various ways

• Shaving cream• Cornstarch and water

The state debate

• Lab 3: The Plasma Experiment– The students learn

about plasma and experiment with the plasma globe

– Materials• Plasma Globe • Fluorescent bulb

The Plasma Experiment

SOLID LIQUID GAS PLASMA

Tightly packed, in a regular pattern

Sometimes vibrate, but do not move from place

to place

Close together with no regular arrangement.Vibrate, move

about, and slide past each other

Well separated with no regular arrangement.

Vibrate and move freely at high

speeds

Has no definite volume or shape and is composed

of electrical charged particles

What happens to the atoms in the different states?

• As more heat is applied, the atoms start to vibrate. The vibration increases as more heat is added to the system. Vibration turns into free movement as the heat gets higher and higher. When more heat is applied, the gas may be ionized: an electron will gain enough energy to escape its atom. This atom is left one electron short and now has a net positive charge; now it is called an ion. In a sufficiently heated gas, ionization happens many times, creating clouds of free electrons and ions; however, not all the atoms are necessarily ionized, and some may remain completely intact with no net charge. This ionized gas mixture, consisting of ions, electrons, and neutral atoms, is called plasma.

What happens to the atoms in the different states?

• Nothing! It just changes states. The amount of matter does not change as a substance is heated or cooled.

• This is called the conservation of matter. Matter is conserved or saved. It doesn’t disappear.

• Let’s think back to our past experiments. Did the crayon disappear after it was melted and cooled?

• Lab 4: Conservation of Matter– Students will learn that matter is conserved as it

goes through physical changes.

Materials• Mass balance• Styrofoam plate• Ice cube

Will it conserve?

References and Links• http://www.dac.neu.edu/physics/b.maheswaran/phy1121/data/

ch04/anim/anim0402.htm (animations)• http://www.harcourtschool.com/activity/states_of_matter/

molecules.swf (flash)• http://www.chem4kids.com/files/matter_plasma.html• http://www.chem4kids.com/files/matter_gas.html• http://www.chem4kids.com/files/matter_liquid.html• http://www.chem4kids.com/files/matter_solid.html• http://www.chem4kids.com/files/matter_changes.html• http://www.chem4kids.com/files/matter_states.html• http://www.chem4kids.com/files/matter_states.html• http://id.mind.net/~zona/mstm/physics/mechanics/energy/

heatAndTemperature/changesOfPhase/changeOfState.html• http://www.bbc.co.uk/schools/scienceclips/ages/9_10/

changing_state.shtml