Chapter 5.2 (Science and Technology 5)

The Water Cycle

Change of state in the water cycle

Activity 5.10: What change of state brings about the water cycle

Work safely in pairs. Study these diagrams that show the water cycle.

  1. Name the different states of water.
  2. In what form is the water in rivers, soils, lakes, wells and seas?
  3. In what form is water in the atmosphere?
  4. How does water in rivers get into the atmosphere?
  5. How does atmospheric water in form of clouds get back to the Earth’s surface?

Learn more. Grow. Share the knowledge with your family and community members

  • Water on the earth surface is in liquid state or solid state as ice. This is called surface water.
  • Surface water exists in rivers, lakes, seas and oceans. This water evaporates when heated by the sun to become water vapour.
  • In the atmosphere, water vapour condenses to form clouds. This is called atmospheric water. The process is called condensation.
  • Atmospheric water falls back to the Earth’s surface as rain. This process is called precipitation.
  • During the rains, surface water runs off to rivers, lakes, seas and oceans. Some of this water seeps through soil to become underground water.
  • Water seeps through soil and gets into plants through absorption by the roots. Animals and humans drink surface water to become part of their body fluid. Human beings access underground water by digging wells and boreholes. We also harvest and store rain water for later use.

Activity 5.11: State the use of change of state in everyday life

  1. In pairs, describe the application of change of state in this picture.
  1. In pairs, describe the application of change of state in this picture.
  1. Have you ever noticed dew on grass in the morning? Where does it go when the sun rises?
  2. How does water placed in a refrigerator become ice? Discuss with your friends.
  3. Some water spilled on the floor. After sometime, the water disappeared. What happened?

Activity 5.12: Find out more about the use of change of state in everyday life

Activity 5.13: Rain-making activity

Safari was helped by his guardian to do this activity. Do it with the guidance of your parent or guardian. Record your observations. Share your findings with other learners.