This key facts covers The Six Changes of State within States of Matter for GCSE Physics. Revise States of Matter in Particle Model for GCSE Physics with 13 exam-style questions and 30 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 6 of 13 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 6 of 13
Practice
13 questions
Recall
30 flashcards
📚 The Six Changes of State
| Change | From → To | Energy | Bonds |
|---|---|---|---|
| Melting | Solid → Liquid | IN (absorbed) | Breaking |
| Freezing | Liquid → Solid | OUT (released) | Forming |
| Boiling/Evaporating | Liquid → Gas | IN (absorbed) | Breaking |
| Condensing | Gas → Liquid | OUT (released) | Forming |
| Sublimation | Solid → Gas | IN (absorbed) | Breaking |
| Deposition | Gas → Solid | OUT (released) | Forming |
Key insight: Energy IN = bonds breaking; Energy OUT = bonds forming
Quick Check: When water boils at 100°C, what is happening to the energy supplied and why does the temperature not rise above 100°C during boiling?
The energy supplied is being used to break bonds between water molecules (increasing potential energy), not to increase their speed (kinetic energy). Since temperature depends on kinetic energy only, it stays constant at 100°C until all liquid has vaporised.