Changes of state
What Changes of state means in Physics GCSE, as defined for AQA, OCR.
Definitions of Changes of state
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Reference: AQA
Melting is solid to liquid, freezing is liquid to solid, boiling and evaporating are liquid to gas, condensing is gas to liquid, and sublimating is solid straight to gas.
Melting and freezing are examples where the original substance is recovered, since melting ice and freezing the water returns the same material.
During melting or boiling the energy overcomes forces between particles rather than raising the temperature, so the temperature stays constant.
Topics that use Changes of state
- Changes of state (AQA GCSE)
- Changes of state (OCR GCSE)
Related terms
- Change in temperature
- conservation of mass
- Energy, mass and specific latent heat relationship
- latent heat
- open and closed containers
- Physical versus chemical change
- Recovery of original properties
- Reversibility
Using Changes of state in the exam
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