can flow easily and can take the shape of the container.
Gases also expand the most when heated.
Fig. 1: Arrangement of particles in solids, liquids and gases
Changes of state
When a solid turns into a liquid, we call it melting.
When a liquid turns into a gas, we call it boiling/evaporation.
When a gas turns into a liquid, we call it condensation
When a liquid turns into a solid, we call it freezing.
The diagram below summarizes these changes of state.
Fig. 2: Changes of state
Kinetic particle theory
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