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Our team of subject expert teachers has prepared and reviewed the NCERT Solutions for Class 6 Science Chapter 14 Water are given here will help you to prepare well and score good numbers in exams.
Water NCERT Solutions for Class 6 Science Chapter 14
Class 6 Science Chapter 14 Water Exercise Questions and Answers
Question 1.
Fill up the blanks in the following:
- The process of changing water into its vapour is called ……………………..
- The process of changing water vapour into water is called ……………………..
- No rainfall for a year or more may lead to ……………………. in that region.
- Excessive rains may cause ……………………..
Answer :
- vapourisation
- condensation
- drought
- flood
Question 2.
State for each of the following whether it is due to evaporation or condensation :
(a) Water drops appear on the outer surface of a glass containing cold water.
Answer:
Condensation
(b) Steam rising from wet clothes while they are ironed.
Answer:
Evaporation
(c) Fog appearing on a cold winter morning.
Answer:
Condensation
(d) Blackboard dries up after wiping it.
Answer:
Evaporation
(e) Steam rising from a hot girdle when water is sprinkled on it.
Answer:
Evaporation
Question 3.
Which of the following statements are ‘true’?
- Water vapour is present in the air only during the monsoon. ( )
- Water evaporates into the air from oceans, rivers, and lakes but not from the soil. ( )
- The process of water changing into its vapour is called evaporation. ( )
- The evaporation of water takes place only in sunlight. ( )
- Water vapour condenses to form tiny droplets of water in the upper layers of air where it is cooler. ( )
Answer:
- False
- False
- True
- False
- True
Question 4.
Suppose you want to dry your school uniform quickly. Would spread it near an angithi or heater help? If yes, how?
answer:
Yes, it will help because the rate of evaporation is increased when the air becomes hot.
Question 5.
Take out a cooled bottle of water from the refrigerator and keep it on a table. After some time you notice a puddle of water around it. Why?
Answer:
We know that water vapour is present in the atmosphere. When a cooled bottle is kept on a table, the water vapours in the atmosphere come in contact with the cooler surface of the bottle and get condensed. The water drops are formed. These water drops are accumulated on the table around the bottle and we notice a puddle.
Question 6.
To clean their spectacles, people often breathe out on glasses to make them wet. Explain why the glasses become wet.
Answer:
Breathed-out air is hot and therefore when it comes in contact with colder glasses than water vapour present in it condenses to form water. This makes the glasses wet.
Question 7.
How are clouds formed?
Answer:
The water vapour that goes into the air rises up along with the air. As the air moves up, it gets cooler and cooler. At sufficient heights, the air becomes so cool that the water vapour present in it condenses to form tiny drops of water called droplets. These droplets are very small, much smaller than even a grain of sand.
These droplets are so small that lakhs of them together would form a drop of water. These tiny droplets remain suspended in the air and move along with it. When these water droplets in the air come closer, they may combine to form slightly bigger droplets. In this way, their size may become larger. Once the size of the droplets becomes larger than a definite size, they appear to us like clouds.
Question 8.
When does a drought occur?
Answer:
A drought occurs when it does not rain at all in continuation for one or two or more years at a place.
Class 6 Science Chapter 14 Water InText Questions and Answers
Activity 1
Take two similar plates. Place one of the plates in sunlight and keep the other under shade. Now, pour an equal amount of water into each of the plates (Fig. 14.1). You can use a cap of a bottle to measure water. Make sure that water does not spillover. Observe the two plates after every 15 minutes. Does the water seem to disappear? From which plate does it disappear first? what is the source of heat for this evaporation?
Answer:
Yes, water seems to disappear. It disappears first from the plate kept in sunlight. The Source of heat for this evaporation is sunlight.
Activity 2
Take a glass half-filled with water. Wipe the glass from the outside with a clean piece of cloth. Add some ice into the water. Wait for one or two minutes. Observe the changes that take place on the outer surface of the glass (Fig. 14.2) and mention what happens.
Answer:
Drops of water appear on the outer surface of the glass containing water with ice.