University of Edinburgh
 

BSL Chemistry Glossary - condensation - definition

Note: this is a long movie so please allow time for it to load.

Definition: If you fill a kettle with water and wait for it to boil you will see steam coming out. Steam is a gas – the particles can move round very easily and there is lots of space between them. When the steam hits a cold surface, the particles cool down and get much closer together. They don't move so much. The steam changes from a gas to water. The process of changing from a gas to a liquid is called condensation.