State of Matter

Key Stage 2

State of matter means whether a material is solid, liquid or gas.

The state of matter can be changed by heating or cooling the material.

Heating can turn a solid into a liquid. This is called melting.

Heating can turn a liquid to a gas. This is called evaporating.

Cooling can turn a gas into a liquid. This is called condensing.

Cooling can turn a liquid into solid. This is called freezing.


Brick is a solid material.	Water is a liquid material.	Inside the balloon is a gas called helium.

State of matter means whether a material is solid, liquid or gas.

The state of matter can be changed by heating or cooling the material.

Heating can turn a solid into a liquid by melting or it can turn a solid straight into a gas by subliming.

Heating can turn a liquid to a gas. This is called evaporating.

Cooling can turn a gas into a liquid by condensing or it can turn a gas into a solid by depositing.

Cooling can turn a liquid into solid. This is called freezing.


This diagram shows the 3 states of matter in the particle model.

Solid	Liquid	Gas
Cannot be compressed.	Cannot be compressed.	Can be compressed.
Does not flow.	Can flow.	Can flow.
Holds its shape.	Fits the shape of the container.	Fits the size and shape of the container.