Changes of State
Physics: Edexcel IGCSE, topic 5.2.1
Changes of State
Objects can change state from one state of matter to another. Melting and boiling are examples of changes of state.
Melting - solid to liquid
- If we heat a solid, the solid particles vibrate more energetically, until they have enough energy to overcome the forces between them.
- This is when the solid melts (becomes a liquid).
- The temperature needed for this to happen is the melting point.
- Melting is sometimes also called fusion.
Boiling - liquid to gas
- If we heat a liquid, the liquid particles move more energetically until they have enough energy to escape completely from the forces between them.
- The particles become a gas and move completely freely.
- The temperature needed for this to happen is the boiling point. Boiling can be called vaporisation.
Test yourself on Changes of State
What is another term for melting point?
When does a liquid boil?