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Solid, Liquid, Gas

What you’ll find out

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No sign-up and no real names. In the lesson you check your understanding as you read, run the experiment yourself, and practise until it sticks.

Three kinds of stuff

Ice is hard and keeps its own shape. We call that a solid. Water pours and takes the shape of whatever cup you put it in. We call that a liquid. Steam spreads out and fills the whole room. We call that a gas.

Heat can change it

Leave ice in a warm room and it melts into water. Heat that water and it turns into steam. Let the steam cool and it turns back into water. It is the same stuff the whole time — only warmer or cooler.

Curriculum links: NGSS 2-PS1-1