Class VI Science 4

10 FILL IN THE BLANKS

1. The process of conversion of water into its vapour state is called evaporation.
2. Ice and water are two forms, or states, of the same substance.
3. When water is converted into its gaseous state, it is called water vapour.
4. The process of conversion of water vapour into its liquid state is called condensation.
5. Ice (solid state) retains its shape irrespective of the container in which it is placed.
6. The process of conversion of a liquid into a solid state is called freezing.
7. The amount of water vapour in the air is also known as humidity.
8. Water (liquid state) does not have a fixed shape but its volume remains constant.
9. When we boil water in a half-filled utensil and cover it with a steel plate, water drops accumulate on the inner side of the plate due to condensation.
10. The circulation of water between the Earth surface and atmosphere is known as the water cycle.

05 COMPETENCY BASED QUESTIONS WITH ANSWERS

1. Thirav and Aavi observe water puddles disappearing and utensils drying. What physical process links these observations?
   Answer:
   The process is evaporation, which occurs continuously even at room temperature.
2. Tiny water droplets appear on the outside of a glass with ice water. Where does this water come from?
   Answer:
   The droplets come from water vapour present in the air, which changes into liquid due to condensation.
3. What conclusion can be drawn about evaporation when water is spread in a plate?
   Answer:
   Evaporation is faster when the exposed surface area is larger.
4. Why does an earthen pot keep water cool?
   Answer:
   Water seeps through the pores and evaporates, producing a cooling effect.
5. How can wet clothes dry faster on a humid day?
   Answer:
   Increase exposed area or air movement using a fan or wind.

05 IMPORTANT QUESTIONS (NO ANSWERS)

1. Explain differences in shape and flow between ice and water.
2. What conditions are required for cloud formation and rainfall?
3. Give examples of substances that change between solid and liquid states.
4. Explain the water cycle and the role of condensation.
5. Design an experiment to prove that water droplets form due to condensation.