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Change of States

Matter can move from one state to another, but can still be the same substance. A
change of state, also called a phase changes, is a physical change from one state
of matter to another, for example, from solid to liquid or from liquid to gas. Come,
let's read more about the change of states.

Heating

Heat can change solids into liquids and liquids into gases.
If ice (solid) is heated, it changes to water (liquid). This change is called melting.
Water (liquid) can change to water vapour (gas). This is called evaporation.
If water (liquid) is heated until it boils, it changes to water vapour (gas) very quickly.
Water boils at 100°C

Cooling
Cooling changes a gas into a liquid, and a liquid into a solid. If water vapour (gas) is
cooled, it changes to water (liquid). This change is called condensation.
If water (liquid) is cooled, it changes to ice (solid). This change is called freezing. Water
freezes at 0°C.

Melts Evaporates
Freezes Condenses

Let’s now learn how to change the states of solids and liquids.
Heat melts a solid and turns it into a liquid. Cooling freezes a liquid into a solid.

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