Solids, liquids and gases



The particle model is a powerful tool which allows us to describe the behaviour of solids, liquids and gases, to predict the ways in which they behave, and to explain how a sample of a substance can change between these states of matter.  This video recaps some of the fundamental concepts which most students cover at Key Stage 3 before going on to look at slightly more complex ideas such as that of the internal energy of a system.

Key Words

gas, melting, freezing, boiling, condensation, kinetic energy, states of matter, internal energy, evaporation, potential energy, solid, sublimation, liquid, physical change