3.1 Matter and Energy

We know that matter is anything that has mass and takes up space. But what is matter made of?

All matter is made up of atoms. The atoms in many forms of matter are joined in molecules. All of these particles move constantly.

If you leave a bottle of perfume open, eventually you will be able to smell the perfume from across the room. Why?

Observations about the movement of particles have helped scientist to develop the kinetic theory of matter.

#1 All matter is made of particles that are in constant motion.

#2 The faster particles move, the higher the temperature of the substance.

#3 At the same temperature, more massive particles move more slowly than less massive ones.

Solid

Liquid

Gas

particles do not move fast enough to slide past one another so they vibrate in place

A solid has definite volume and a definite shape.

Strong attractions hold them close together to create a rigid structure

Ex. Ice

particles in a liquid move more quickly than those in a solid. This allows the particles to overcome some of the forces of attraction between them

Liquids can flow freely.

Have definite volume and variable shape

Ex. water

particles move quicker than in solid and liquid. They are usually far apart.

Can change shape

Variable volume and shape

Ex. carbon dioxide

A fluid is a state of matter in which the particles are free to move past each other

Because liquids and gases have variable shapes, they are considered a fluid

Plasma is made up of electrically charged, or ionized particles.

Plasmas have variable shape and volume but unlike gases, can conduct electricity.

Energy is the ability to change or move matter

Energy of motion is called KINETIC ENERGY. Because they are moving, all particles of matter have kinetic energy. Solids have the least kinetic energy while gases have the most kinetic energy.

The total kinetic energy of all particles in a substance is called thermal energy.

a measurement of the average kinetic energy of the particles in an object

When you measure an object's temperature, you are measuring the average kinetic energy of its particles. The higher the average kinetic of the particles in a substance, the higher its temperature.