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Find out about these reversible processes.

 Square character looking at a glass of ice.
Image caption,
As the ice heats up, it melts and turns into water.

Freezing and melting

Solids and liquids can be changed from one state to another by heating or cooling.

Heat melts a solid and turns it into a liquid. Cooling freezes a liquid into a solid.

Heating

If ice (solid) is heated, it changes to water (liquid). This change is called melting.

Cooling

If water (liquid) is cooled, it changes to ice (solid). This change is called freezing. Water freezes at 0掳C

 Square character looking at a glass of ice.
Image caption,
As the ice heats up, it melts and turns into water.

Times tables 1-12!

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Times tables 1-12!

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