states of matter - mrs. mccarrey's 7th grade...

STATES OF MATTER

MATTER IS MADE OF…

•Atoms and molecules!

WHY DO CLOUDS MOVE?

• Do you see anything pushing on clouds?

• Can invisible things move?

FLASHLIGHTS AND DUST…

• Look in the beam of light. Do you see particles in the air?

What could make a dust particle move?

• Look at the flashlight itself. Are the atoms inside it moving?

DIFFUSION

•The movement of molecules from a high

concentration to a low concentration is called

diffusion.

PARTICLES

(A particle is a small piece of something.)

•Particles are in constant motion and are

always bumping into each other.

STATES OF MATTER

•There are three main states (or types) we

find matter in. These are:

•SOLID

• LIQUID

•GAS

SOLID

• Solids have a definite shape and volume – the shape

and volume don’t change unless we do something to it.

• The particles of a solid are very close together.

• They don’t move around very much – they simply

vibrate in place.

• This is why it’s harder to break

solids into pieces than liquids.

SOLID

SOLID to LIQUID• If you increase the temperature of a solid, it will

eventually turn into a liquid! Changing states from

solid to liquid is called melting.

When you put ice in water, the ice

doesn’t cool down the water –

the water gets cold because

it’s heating up the ice cube!

LIQUID to SOLID•Removing energy from a liquid turns it into a solid.

Changing states from liquid to solid is called

freezing.

•Freezing is the opposite of melting, so they occur at

the same temperature!

LIQUID

• Liquids have a definite volume but take the shape of their container.

•Viscosity is how thick a liquid is. (The thicker it is, the more

viscous it is.)

LIQUID

•Particles of a liquid are close together, but they move fast

enough to slide past each other.

LIQUID to GAS

•Changing states from liquid to gas is called

evaporation.

•Boiling is the evaporation at a liquid’s boiling point,

but evaporation does

not have to be at a

boiling point to occur.

GAS to LIQUID

•Changing states from gas to

liquid is called condensation.

•Condensation happens when large numbers of gas

particles clump together. Removing energy from them

makes them slow, and then they stick together because

they’re not fast enough to move past each other.

GAS

•Gases have no definite shape and no definite volume.

•One small tank of helium can fill almost 700 balloons.

• Particles in gas move quickly and can break away from each

other completely.

GAS

SOLID to GAS

•Changing states from solid to gas is called

sublimation.

•When this happens, the solid does not melt but goes

straight to being a gas.

•The opposite of sublimation is called deposition.

You should be able to draw the arrangement of particles in all three states of matter…

TEMPERATURE OF PARTICLES

TEMPERATURE OF PARTICLES

•When you increase the temperature…

•Particles move more quickly!

•Particles expand!