Changes In States Of Matter For Water


8.2  Changes In States Of Matter For Water
  • Water exists in three states, namely:
  1. Solid (ice)
  2. Liquid (water)
  3. Gas (water vapor)
  • When water is heated and cooled, it will change to another form.
Changes in states of matter for water
  • Water can change from one state of matter to another state of matter.
  • Water matter can change its state through the processes of freezing, melting, boiling, evaporation and condensation.

Clouds & rain
  • The movement of water from the earth’s surface to the air forms clouds & eventually descends back to the earth’s surface as rain
  • This process is repetitive & is known as the natural water cycle
  • The formation of clouds & rain results from the process of changing in state of matter of water
  • The natural water cycle ensures that the quantity of water is always sustained on the earth’s surface through the formation of clouds & rain
  • This cycle involves the process of evaporation & the process of condensation

  1. A - Heat from the Sun causes the process of evaporation to take place. Water evaporates from the earth's surface such as land, oceans, rivers & lakes into water vapor.
  2. B - Water vapor that accumulates & cools will condense into fine water droplets & form clouds.
  3. C - As the clouds rise higher in the sky, the cold air causes the water droplets to merge to become larger & heavier which then fall back to earth as rain.
  4. D - Rainwater is absorbed into the earth & will flow back into lakes, rivers & oceans.