Water, Ice, and Vapor

There are three different types of water, which are called states. When ice melts, it changes to water. Heat causes water to evaporate, changing it into vapor. When water freezes into ice or condenses from vapor to a liquid, a little bit of heat is released. The heat that is needed for, or released from, these changes in state is called latent heat.


  • When it is a solid we call it ice.
  • When it is a liquid we call it water.
  • When it is a gas we call it vapor.



Have you ever noticed that your skin feels cold when you get out of a swimming pool, lake, or ocean on a windy day? It feels much colder than if you were dry. That’s because wind helps the liquid water on your skin to evaporate becoming water vapor, and a little latent heat is needed for this change. In this case, the heat comes from you!


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