Science·Matter & Materials·conceptual
How Materials Change State
Explain melting, freezing, boiling, condensing, and sublimation using the particle model, interpreting heating and cooling curves to identify melting and boiling points
Suggested ages 11–12
Evidence of understanding
- Describes what happens to particles during each change of state
- Reads a heating/cooling curve and identifies the melting point and boiling point from the flat regions
- Explains why temperature stays constant during a change of state
- Distinguishes between evaporation (from surface, any temperature) and boiling (throughout liquid, at boiling point)
Assessment prompt
If How Materials Change State was heating a block of ice in a pan and drew a graph of temperature over time, could they explain why the line goes flat at certain points — and what's happening to the particles when it does?
Standards alignment
KS3.Sci.Chem.PNM.2GB · uk-nc-2013
Changes of State
The national curriculum in England: Key stages 1 and 2 framework document · KS3
KS3.Sci.Chem.PNM.4GB · uk-nc-2013
Particle Arrangements and Motion
The national curriculum in England: Key stages 1 and 2 framework document · KS3