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During boiling the volume of water increases very much.
During condensation a strong decrease of volume takes place.
* Fill 10 ml of water into a Cola can.
* Boil the water using a micro burner (protect your fingers using  wet tissue paper).
* Quickly dip the can bottom up into a container full of cold water.
Observation: The can collapses with a bang.
Explanation: * During boiling 300 ml of air in the can is replaced by steam.
* By dipping the can into cold water, 300 ml steam are suddenly transformed into less than 1 ml
   liquid water resulting in a negative pressure: The can is crushed by the outer air pressure.