Science
Matter & Materials
Conceptual
11–12 yrs
How Materials Change State
材料如何改变状态
Description
Explain melting, freezing, boiling, condensing, and sublimation using the particle model, interpreting heating and cooling curves to identify melting and boiling points
Mastery Evidence
- 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 your child 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?
