What is evaporation?

 
  Fig. 1-15 We dry clothes by hanging them.

You probably dry wet clothes by hanging them out of windows. The water will go into the air and in a day or so and the clothes will be dry. The water on the clothes is well below the boiling point, so the process of boiling is not involved. In fact, the water changes into water vapour in a process called evaporation.

Evaporation is the change of state from liquid to gas below the boiling point. Boiling only takes place at the boiling point, but evaporation can take place in any temperatures below the boiling point. In addition, evaporation only takes place on the surface of a liquid, whereas boiling takes place everywhere within the liquid.

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