Class 6 Science Chapter 8 Extra Questions A Journey through States of Water
Class 6 Science Chapter 8 A Journey through States of Water Important Extra Questions and Answers
A Journey through States of Water Class 6 Extra Questions Very Short Answer Type
Question 1.
Look at the figure and write down the activities shown in the figure in which water is being used. NCERT Exemplar
Answer:
(a) A man washing clothes.
(b) A man taking a bath.
(c) A woman pulling out water from well for drinking and carrying out household chores.
Question 2.
Write any two activities which require more than a bucket of water. NCERT Exemplar
Answer:
(a) Giving water (irrigation) to a crop field.
(b) Washing a large amount of clothes or utensils.
Question 3.
Write any two activities which require less than a bucket of water. NCERT Exemplar
Answer:
(a) Brushing teeth
(b) Watering a plant
Question 4.
What are the three states of water?
Answer:
Solid, liquid and gas.
Question 5.
How can water be changed to ice?
Ans.
By placing water in a cold environment such as freezer.
Question 6.
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 7.
Name a common example of condensation that you can see in your daily life.
Answer:
Water droplets on the outside of a glass of cold drink.
Question 8.
Why does the mirror in the bathroom fog up after a hot shower?
Answer:
The water vapour from the hot shower condenses into tiny droplets on the cooler mirror surface due to condensation.
Question 9.
What is atmospheric water generator?
Answer:
It is a machine which collects water from humid air to produce drinkable water.
Question 10.
When you leave a glass of water outside on a hot day, why does the water level decrease?
Answer:
The water evaporates into the air due to the heat from the sun.
Question 11.
Why do wet streets dry out more quickly after rain when the weather is warm and sunny?
Answer:Warm and sunny weather increases the rate of evaporation of the water on the streets.
Question 12.
In which case evaporation is faster, water in a cup or water splashed on the table?
Answer:
Water splashed on the table will be evaporated faster as its area exposed to air is larger.
Question 13.
Name one example of a process that causes cooling due to evaporation.
Answer:
Sweating.
Question 14.
What is the main source of energy that drives the water cycle?
Answer:
The Sun.
Question 15.
How does evaporation contribute to the water cycle?
Answer:
It adds water vapour to the air, which eventually forms clouds.
Question 16.
How does the water cycle start?
Answer:
With evaporation of water from oceans, lakes and rivers.
Question 17.
What is the term used for water falling from the clouds as rain, snow or hail?
Answer:
Precipitation.
A Journey through States of Water Class 6 Extra Questions Short Answer Type
Question 1.
Why is there a need for conserving water? Give two reasons. NCERT Exemplar
Answer:
Conserving water is important because
(a) supply of fresh, usable water is limited.
(b) growing demand can lead to shortage of water in future.
Question 2.
Compare the properties of ice, liquid 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 vapours, both shape and volume change, it occupies all available space.
Question 3.
Give three examples of evaporation in our household.
Answer:
(i) Drying of wet clothes
(ii) Drying of mopped floor
(iii) Drying of sweat from out body.
Question 4.
In a science experiment, you heat a pot of water on the stove and observe steam rising from it. What state change is occurring in the water and what is this process called? Competency Based Ques.
Answer:
The water is changing from a liquid to a gas (water vapour/steam) through the process of evaporation.
Question 5.
Why do wet clothes placed on a clothes line get dry after some time? Explain. NCERT Exemplar
Answer:
When you place wet clothes on a clothes line, they are more exposed to air and sunlight. This causes the evaporation of water in the wet clothes into water vapour, and the clbthes get dried after sometime.
Question 6.
What effect does a high temperature have on the rate of evaporation?
Answer:
Higher temperatures increase the rate of evaporation.
Question 7.
Water kept in sunlight gets heat from sun and is evaporated. But how does water kept under the shade of a tree also gets evaporated? Explain. NCERT Exemplar
Answer:
Even under the shade of the tree, the water is still exposed to the air. This air movement helps in evaporation of water, as it helps to carry away the water vapour as it forms, allowing more water to evaporate.
Question 8.
What is the effect of high humidity on sweating?
Answer:
It makes sweating less effective at cooling the body because the high humidity levels mean the air already has more amount of water or has more humidity. So, the rate of evaporation decreases as the air can hold less additional water vapour.
Question 9.
Why do you feel sticky and uncomfortable on a humid day?
Answer:
High humidity makes it harder for sweat to evaporate from your skin, so you feel sticky and warm.
Question 10.
How does using a fan help you to cool down in a hot room more quickly?
Answer:
The fan increases airflow, which speeds up the evaporation of sweat from your skin, making you feel cooler.
Question 11.
What role do trees play in the water cycle?
Answer:
Trees release water vapour into the air from their leaves, through the process of transpiration, and thus, contributes to the formation of clouds.
Question 12.
Why is water cycle important?
Answer:
The water cycle is important for us because of the following reasons.
1. Water cycle helps in regulating weather on earth.
1.Water cycle makes water available in its various forms on the earth. The most important is the rain water.
Question 13.
How do the areas covered with concrete affect the availability of ground water?
Answer:
Concrete surfaces do not allow the water from seeping into the ground. Since concrete is hard and impermeable, rainwater cannot pass through it easily. Thus, areas covered with concrete have less or no availability of ground water.
A Journey through States of Water Class 6 Extra Questions Long Short Answer Type
Question 1.
During a hot summer, Rita uses a spray bottle to mist her face to feel cooler. Competency Based Que.
(i) Explain why misting with water makes her feel cooler and how this is related to evaporation.
(ii) What factors can affect the rate of this process?
Answer:
(i) Misting with water makes her feel cooler because as the water evaporates from her skin due to hot conditions, it gives a cooling effect.
(ii) Refer to text on page no. 117.
Question 2.
Explain how the process of evaporation helps in cooling the surroundings. Provide examples of everyday situations where this cooling effect is noticeable.
Answer:
Refer to text on page no. 118.
Question 3.
How does condensation contribute to the formation of clouds?
Answer:
Refer to text on page no. 118 .
Question 4.
Describe the process of the water cycle in detail.
Answer:
Refer to text on page no. 118 and 119.
Question 5.
Most of the water that falls on the land as rain and snow, sooner or later goes back to a sea or an ocean. Explain how it happens?
Answer:
Water falls from the sky to the ground as rain, snow or hail. This is called precipitation. After falling, the water collects in various places such as rivers, lakes and streams. Some of the water flows over the ground in rivers and streams. This flow of water is known as runoff. As rivers travel, they pick up more water from smaller streams and lakes. Eventually, all the rivers and streams flow into larger bodies of water, ‘such as seas or oceAnswer:Thus, most of water sooner or later goes back to a sea or an ocean. In the oceans and seas, water evaporates back into the air, forming clouds. ‘This water will eventually fall again as precipitation, continuing the water cycle.
A Journey through States of Water Class 6 Extra Questions Skill Based
Question 1.
Solve the following crossword puzzle by using the hints given below
Hints..
Answer:
(ii) _______ state of water has no fixed shape but has a definite volume.
(iv) Water in the steel plate disappears after sometime due to _______ .
(v) Liquid candle wax turns into _______ on cooling.
(i) Evaporation causes _______.
(iii) Rate of evaporation _______ with decrease in surface area of the water exposed for evaporation.
Question 2.
Discuss with your friends the impact of human activities on the water cycle. Provide examples of how activities like deforestation, urbanization, and pollution affect water availability and quality.
Answer:
Human activities have significant impact on the water cycle. Some examples include :
(i) Deforestation Cutting down trees reduces the amount of water which is absorbed by the soil and returned to the atmosphere through transpiration. This can lead to reduced rainfall and disrupt the natural water cycle. Moreover, without trees, soil erosion increases which leads to sedimentation in water bodies that reduces water quality.
(ii) Urbanization Due to urbanization, natural land is replaced by imperable surfaces such as concrete that reduces the ability of rain water to infitrate the ground. This leads to increased surface run off, flooding and decreased ground water recharge. Thus, it affects both water quality and quantity.
(iii) Pollution Human activities like industrial waste water discharge and improper waste disposal contaminate water sources. This affects water quality, making it unsafe for drinking and also harm aquatic ecosystem. Moreover, polluted water sources reduces the availability of clean water for human consumption and other uses.
Question 3.
Explain the concept of water conservation and why it is important for maintaining a sustainable water supply. Discuss methods individuals and communities can use to conserve water. Research Skill
Answer:
Water conservation is a process of preventing wastage of water, using water carefully and recharging ground water. Maintaining a suistainable water supply is important because water is a finite and irreplaceable resource essential for human life and without proper management, current water needs could deplete future availability. This will impact socio-economic development, ecosystem and human survival itself.
Method individuals and communities can use to conserve water are as follows :
(a) Individuals can conserve water by turning off taps while brushing teeth, using water-efficient appliances, taking short showers etc.
(b) Communities can conserve water by implementing rain water harvesting systems, using efficient irrigation techniques etc.