Principle

Water vapour is conducted into a calorimeter containing cold water. From the mix temperature and the mass increase of the cold water, the specific heat of condensation of water is calculated. It is as large as the specific heat of vaporisation of water; i.e. the heat required for vaporisation is released on condensation.

The student gains a feeling for the size of this quantity of heat when he mixes the same quantity of boiling water - instead of water vapour - with the cold water. The calculation of this mix temperature is undertaken in point 3 of the evaluation. However, the impression on the students is even more lasting when this supplementary experiment is conducted.

Benefits

• Real stand material for an esecially stable and safe setup
• Own construction of a calorimeter deepens the understanding
• Student-suitable experiment descriptions with reports available