What is Matter Grade 7 Science

The Particle Theory of Matter

helps to explain what scientists have learned about these tiny particles of matter.

mixtures

matter that contain two or more pure substances mixed together.

pure substances

matter that contains only one kind of particle.

What the five main ideas of the Particle Theory

1. All matter is made up of tiny particles. 2. Particles have empty spaces between them. 3. Even though you cannot see them, particles are moving randomly all the time. 4. Particles move faster and spread farther apart when they are heated. 5. Particles attract each other, so they tend to stay together rather than fly apart.

Gas

a state of matter that does not have a definite volume or a definite shape; a gas takes the shape and volume of its container.

Liquid

a state of matter that does not have a definite volume, but no definite shape; a liquid takes the shape of its container.

Solid

a state of matter with a definite volume and a definite shape.

Matter

anything that takes up space and has mass.

Chemistry

the study of matter and its changes.