S2.4.1 For the adult
Solids, liquids and gases
Why does water change shape, but a stone does not?
What this chapter teaches
A solid keeps its shape. A liquid takes the shape of its container but keeps its amount. A gas spreads to fill any container. Sand and salt pour, but each grain is a solid.
Three questions to ask
There is no one right wording. Listen for the idea.
- Why is sand a solid even though it pours?
- What happens to the shape of water when you pour it from a cup into a bowl?
- How is a gas different from a liquid in a closed jar?
After the chapter, the learner can
- Sort materials into solids, liquids and gases
- Describe how each one keeps or changes its shape
What they copy into their notebook
A solid keeps its shape. A liquid takes the shape of its container, but the amount stays. A gas spreads to fill any container. Sand pours, but each grain is a solid.