Class 6 Science Chapter 8 Extra Questions and Answers A Journey through States of Water
NCERT Class 6 Science Chapter 8 A Journey through States of Water Important Extra Questions and Answers
Investigating Water’s Disappearing ACT Class 6 Extra Questions
Question 1.
After rain water puddles appear in the playground. After some time these disappear. Where does the water go?
Answer:
Water gets absorbed by the soil on the playground. It also evaporates.
Question 2.
After washing the utensils, water remains on the surface of utensils. After sometime it dries. Where does the water disappear?
Answer:
Water from the surface of utensils evaporates with time.
Question 3.
Do you heat the pan to observe evaporation?
Answer:
No. Evaporation takes place at room temperature also.
Question 4.
Give three examples of evaporation.
Answer:
- Drying of wet clothes
- Drying of mopped floor
- Drying of sweat from our body.
Question 5.
Where does hand sanitizer disappear as you rub it in your hands.
Answer:
It disappears due to evaporation because on rubbing hands heat is produced.
Question 6.
While making dosa, we sprinkle some water on the hot pan. Soon it disappears. Where does it go?
Answer:
It converts into steam.
Nother Mystery Class 6 Extra Questions
Question 1.
Take a tumbler with cold water. Keep it for some time. What do you observe?
Answer:
Some water droplets appear on the outer surface which become bigger with time due to condensation.
Question 2.
Suggest possible reasons explaining’the appearance of water droplets on the outer surface of the glass tumbler containing lemonade.
Answer:
Water does not come out from the glass tumbler. Water in the air deposits on the outer surface of the glass tumbler. This is due to condensation.
Question 3.
Give another example of condensation similar to water droplets on the outside tumbler containing cold water.
Answer:
Appearance of dew drops on the plants in the morning.
What are the Different States of Water Class 6 Extra Questions
Question 1.
Name a substance that can be observed in three different states.
Answer:
Water
Question 2.
How do you get three states of water?
Answer:
Take some ice. Heat it. It melts and gets converted into water. On further heating water gets converted into its gaseous state, i.e., vapours.
Question 3.
Compare the properties of ice, liquid water and water vapour.
Answer:
The shape and volume of ice does not change when shifted from one container to another. In case of water, shape depends on the container but volume remains the same. In case of water vapour, both shape and volume change. It occupies all available space.
| Property | lee (solid state) | Water (liquid state) | Water vapour(gaseous state) |
| 1. Ability to flow | No | Yes | Yes |
| 2. Ability to spread | No | Yes | Yes |
Question 4.
State some examples where three states are exhibited.
Answer:
Wax, oil and ghee.
Question 5.
Give example of four gases which spread if left-open.
Answer:
Smell of yummy food from cooking, oxygen, carbon dioxide and LPG (Liquefied petroleum gas). Oxygen and carbon dioxide do not smell and are not noticeable.
How can We Change the States of Water Class 6 Extra Questions
Question 1.
What is melting?
Answer:
The process of conversion of a solid into liquid is called melting.
Question 2.
What is freezing?
Answer:
The process of conversion of liquid into solid state is called freezing.
Question 3.
How can you change ice to liquid state and then to vapour?
Answer:
By supplying heat slowly and continuously we can change ice to liquid ~ water and then to vapour.
Question 4.
How do you change water to ice?
Answer:
By placing water in a cold environment such as freezer.
Question 5.
Name two examples other than water where you observe liquid to solid change and vice versa.
Answer:
Wax and coconut oil.
Question 6.
What is atmospheric water v generator (AWG)?
Answer:
This machine collects water from humid air and gives drinking water through the process of condensation.
How can Water be Evaporated Faster or Slower Class 6 Extra Questions
Question 1.
In which case evaporation is faster-water in a bottle or water on a plate?
Answer:
The water on a plate will evaporate faster as its area exposed to air is larger.
Question 2.
Why do wet clothes placed on a clothes line get dry after some time? Explain.
Answer:
Wet clothes placed on a clothes line get dry after some time because water present in wet clothes is converted into water vapour due to evaporation and leaves them dry.
Question 3.
Water kept in sunlight gets heat from sun and is evaporated. But how does water kept under the shade of a tree also get evaporated? Explain.
Answer:
Air around us gets heated from sunlight. This warm air provides heat for evaporation of water kept in the shade.
Question 4.
How do the areas covered with concrete affect the availability of ground water?
Answer:
Areas covered with concrete reduce the seepage of rain water into the ground and this reduces the availability of ground water.
Question 5.
Why is there a need for conserving water? Give two reasons.
Answer:
The two reasons for the need for conserving water are:
- Increasing population needs more water.
- Availability of water is decreasing day-by-day.
Cooling Effect Class 6 Extra Questions
Question 1.
Which of the two- water in earthen pot or water in stainless steel pot will give cold water after being left for some time? Illustrate with another example.
Answer:
Water in the earthen pot will be cold. It is because water from the surface of the earthen pot evaporates and imparts a cooling effect on water. On the other hand, water in stainless steel will not give cold water.
Another Example: We cool the surface of the roof or floor by sprinkling water over it. Surahi is also used for similar purpose.
How do Clouds give us Rain Class 6 Extra Questions
Question 1.
Name the process which helps to bring evaporated water back to the earth’s surface.
Answer:
Condensation.
Question 2.
How does condensation help to form clouds? What causes rain?
Answer:
When air moves higher above the earth’s surface, it becomes cooler and cooler. At certain heights, the cooled vapour turns into droplets. When these droplets surrounded the dust particles, it forms clouds. When these cloudy droplets join together, it starts rain because drops are quite heavy and start falling.
Question 3.
What is water cycle?
Answer:
The water from the ocean and Earth’s surface evaporates into the atmosphere as vapour. In due course of time it forms heavy clouds of water and dust droplets due to condensation. This then falls as rain, hail or snow, ultimately flowing to the oceans. This cycle of water is called water cycle.
Question 4.
Name the natural processes leading to water cycle.
Answer:
Evaporation and condensation.
