An explanation of latent heat energy. When substances change state, they either give out or take in heat energy. For a pure substance, the temperature of boiling or melting takes place at a constant temperature.
- This clip is from:
- First broadcast:
- 20 March 2008
The clip can form part of lessons on energy transfer. Explain the concept of latent heat to the class and discuss why water boils at a constant temperature and why this in turn ensures that the eggs cook at the same rate. After watching the clip, students should recognise that a change of state does not involve a change of temperature and that energy is gained or lost by a substance when its state is changed.