Hey there, looking sharp.
You're going to show us how to change the state of a substance by heating or cooling it, with the aid of these temperature controlled rooms.
When solids are heated they can melt into liquids. And when we freeze a liquid it becomes a solid.
Hadn't you better check on them?
Right. After being heated, the ice has melted into water.
For water this melting point is zero degrees celsius.
And it looks like you've done a fair bit of melting yourself.
When we freeze water it becomes ice.
It's changed from a liquid into a solid.
This happens when the temperature drops below zero degrees celsius.
Someone here's become a big icy too.
But of course, freezing and melting are totally reversible processes.
So! Who wants another go?