THE STATES OF MATTER

Matter exists in different physical states.

States of matter are the different forms in which matter can exist.

Common states of matter include: solids, liquids and gases.

Plasma is considered the fourth state of matter, and includes the sun and all stars.

When substances change from one state to the other, the molecules in that substance do not change, however the arrangement of molecules does change.

Molecules are not created or destroyed and the size does not change.

The state of a substance depends on the distance between it's molecules or atoms, and on the way in which the molecules or atoms attract.

VAPORIZATION

• When the state of the object changes from a liquid state to a gas state

CONDENSATION

• When the object changes state from a gas state to a liquid state

FREEZING

• When the state of matter is changed from a liquid state to a solid state

MELTING

• Is the process of changing the object state from a solid state to a liquid state

WHEN DOES HEATING AND COOLING

Thermal Energy:
The energy within the object due to the motion of atoms or molecules within the object.

Heat is a term used to describe when we are transferring thermal energy from one object to another

SOLID

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• A solid is a substance that has a definite volume and a definite shape.
• In a solid, the atoms are very attracted to one another.

The atoms vibrate but stay in fixed positions because of their strong attractions for one another

Heating a solid increases the motion of atoms

Cooling a solid decreases the motion of the atoms.

A decrease in the motion of the atoms allows the attractions between the atoms to bring them a little closer.

LIQUID

A liquid has a fixed volume but not a fixed shape. Liquids take the shape of the container they are in.

Heating a liquid increases the speed of the molecules.

An increase in the speed of the molecules competes with the attraction between molecules and causes molecules to move a little further apart.

Cooling a liquid decreases the speed of the molecules.

A decrease in the speed of the molecules allows the attractions between molecules to bring them a little closer together.

GAS

A gas has no fixed volume or shape.

A gas can take both the shape and volume of its container.

In a gas, the molecules have very weak attractions for one another.

Molecules in a gas are able to move freely past each other with little interaction between them

The molecules of a gas are much more free and move independently compared to the molecules of liquids and solids.

Heating a gas increases the speed of its molecules. Cooling a gas decreases the speed of its molecules.

Whether a substance is a solid, liquid, or a gas at a certain temperature depends on the balance between the motion of the atoms or molecules at that temperature and how strong their attractions are for one another.