大象传媒

Solids, liquids and gases

The of is a model that describes the arrangement, movement and of in a substance. The model is used to explain the of solids, liquids and gases.

Learn more on states of matter in this podcast.

Particle arrangement and movement

The table below shows a comparison of the same substance in three different states.

Table showing diagrams of solid, liquid and gas, their particle arrangements, movement and closeness.

The particles in the diagrams could be , or depending on the type of substance, eg ionic compounds, small molecules, giant molecules, and metals.

Explaining properties

A single particle does not have the properties of the material it is part of. The properties of a substance are the properties of a huge number of particles together.

Solids:

  • have a fixed shape and cannot flow, because their particles cannot move from place to place
  • cannot be (squashed), because their particles are close together and have no space to move into

Liquids:

  • flow and take the shape of their container, because their particles can move around each other
  • cannot be compressed, because their particles are close together and have no space to move into

Gases:

  • flow and completely fill their container, because their particles can move quickly in all directions
  • can be compressed, because their particles are far apart and have space to move into