Materials exist as solids, liquids and gases, and as a mixture of these states. They may be natural or man made and they have different textures and properties.
Some solids are hard and strong, others are flexible. Most solids will melt when heated and liquids evaporate to form a gas.
Cartoon animations explain in simple terms why different materials have different properties and how they change on heating and cooling. Other animations cover separating solids from liquids and show what happens to a solid when it dissolves in a liquid.
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