Knowledge database: Basics: States of matter

There are three basic states of matter: solid, liquid and gas. Plasma could also be mentioned as a state of matter which is actually ionized gas.

In the solid state, particles are very densely arranged under the influence of strong chemical bonds. Because of these strong bonds, solids have a constant shape and volume, unless one changes that state by using a certain amount of energy. There are two basic types of solids: crystalline and amorphous. In crystalline solids, the particles are mutually arranged in a precise crystal structure with constant dimensions. Amorphous materials show no proper arrangement of the particles. As examples of such substances, one can mention glass and common wax.

The liquid state is characterized by somewhat weaker but still persistent bonds between the particles. For liquid substances, it is characteristic that they have a constant volume (if the temperature and pressure are constant), but no permanent shape - they adapt to any container or generally any volume in which they are located.

With the gaseous state, attractive forces between the particles are very weak, causing the particles of matter to move freely in space. A typical property of gas is that it has no constant shape, or volume. It is scattered throughout any volume that it has at its disposal.

The diagram above shows various possible transitions from one state to another.