Brainlag PlusInternal energy, heating and cooling curves, and why the temperature stops rising while a substance melts or boils.
Energy stored by particles
The particles in a substance have kinetic energy (they move) and potential energy (from the forces holding them together).
Together these are its internal energy.
Heating a substance raises its internal energy. Either:
- the particles move faster, so the temperature rises, or
- the bonds between them are broken, so the state changes, with no change in temperature.
Changes of state are physical changes: the mass stays the same and the change can be reversed.
The rest of this lesson and its 9 practice questions are in Plus.
Screen 1 of 3, free to read.
- 9 exam-style questions, marked as you go, each with a worked solution
- Anything you get wrong is saved to your flashcards