The Particle Theory of Matter:

1. Matter is made up of tiny particles (Atoms & Molecules)

2. Particles of Matter are in constant motion.

3. Particles of Matter are held together by very strong electric forces

4. There are empty spaces between the particles of matter that are very large compared to the particles themselves.

5. Each substance has unique particles that are different from the particles of other substances

6. Temperature affects the speed of the particles.  The higher the temperature, the faster the speed of the particles.

The particle theory of matter explains the following scientific phenomena:

  1.  Pure substance are homogeneous (one phase - one unique kind of particle)
  2.  Physical Changes - Melting, Evaporation, Sublimation, Dissolving.....
  3.  Characteristic Physical Properties - Density, Viscosity, Electrical & Thermal Conductivity