DAV Class 5 Science Solution Chapter 10 Air
DAV School Books Class 5 Science Solution Chapter 10 Air all Question Answer. DAV Class 5 10th Chapter Air full Chapter explanation by expert teacher.
A.) Fill in the blanks.
Answer: (1) nitrogen, oxygen (2) oxygen (3) carbon dioxide (4) photosynthesis (5) Ozone (6) polluted air.
B.) Write True or False for the following statements.
1.) Pure air is colourless, odourless and tasteless.
2.) An empty glass bottle contains air.
3.) Air gets impure due to the presence of nitrogen gas.
4.) Leaves of a plant look greener before rain.
5.) Oxygen is required for burning.
Answer: (1) True (2) True (3) False , it gets impure due to carbon monoxide, sulphur dioxide(4) False, they look greener after rain (5) True.
C.) Tick the correct option.
1.) The gas, which is present the most in air, is-
Answer: nitrogen
2.) An air pollutant, which exists in solid form, is-
Answer: smoke
3.) The gas, whose amount varies with weather changes, is-
Answer: water vapour
4.) The gas, that gets reduced, through the process of photosynthesis, is-
Answer: carbon dioxide
5.) When sulphur dioxide reacts with water and oxygen in air, it results in the production of-
Answer: acid rain
D.) Answer the following questions in brief.
1.) Name the main components of air.
Air is composed of Oxygen, Nitrogen , other gases and water vapour.
2.) State the meaning of the term ‘Photosynthesis’.
Answer: The process by which plants produce their own food with the help of carbon dioxide water and other important nutrients in the presence of sunlight is known as photosynthesis
3.) State two possible harmful effects of ultraviolet rays.
Answer: Ultraviolet rays can cause skin cancer if one is exposed to it it can also affect the growth of plants
4.) Define the term ‘Air pollutant’.
Answer: When the air gets introduced to impurities such as carbon monoxide, nitrogen and sulfur .These compounds are known as air pollutants
5.) Name any two of the gaseous pollutants present in air.
Answer: two gaseous pollutants are carbon monoxide and ozone
6.) List any four causes of air pollution.
Air pollution is caused by-
Smoke emitted from vehicles
Smoke from burning of coal in factories
Burning of wood or garbage or dry leaves
Smoke from forest fires.
E.) Answers the following questions.
1.) Why is air necessary for animals?
Answer: Animals require air because it has certain components such as oxygen and other gases as well that are required for .animals do exist. oxygen is one of those gases the humans as well as other animals inhale oxygen and give out carbon dioxide oxygen is essential for our breathing. Other than that oxygen is also required for a chemical process known as burning. other than that plants use both carbon dioxide as well as air to prepare its food by the process of photosynthesis.
2.) How is nitrogen important for plants?
Answer: Nitrogen helps in the growth of plants. It also helps the seeds and fruits to grow in shape and size. the plants absorb nitrogen but they are unable to do it directly hence a special type of bacteria which is there in the soil helps to convert nitrogen into certain forms of nitrogen that can be absorbed by the plants.
3.) How is the balance of oxygen and carbon dioxide in air, maintained in nature?
Human beings breathing oxygen that it receives and breathes out carbon dioxide. it is important to notice that this would ultimately lead in an increase in the level of carbon dioxide. However plants utilize this carbon dioxide in the process of food making known as photosynthesis as a result the amount of carbon dioxide is consumed and becomes lesser. as a byproduct of photosynthesis it gives out oxygen.
4.) Why is ‘acid rain’ harmful?
Answer: acid rain is harmful because the concentrated acids that precipitates along with the rain can corrode limestones and kill plants as well as cause skin diseases in humans
5.) Why should we feel worried about ‘global warming’?
Answer: An Increase in global warming or the increased greenhouse effect can cause difficulty for. Humans because it would eventually lead to an increase in the average temperature of earth. this could lead to increase in the melting of ice caps in the poles and cause immense flooding throughout the world
6.) Suggest some ways of reducing air pollution.
Answer: to reduce air pollution we must follow the following steps
We should resort to reforestation and plant more and more trees.
Use vehicles with the cleaner fuel instead of using regular fossil fuel that causes a lot of air pollution.
Vehicle should be taken off for a pollution level check on a regular basis so that they can be repaired before they can cause a lot of damage to the nature.
Tall chimney should be made in factory so that the smoke emitted by them is released in a higher altitude of the atmosphere is released in a higher altitude of the atmosphere.
7.) How does planting of trees help in making air cleaner?
Planting can make the air cleaner as it takes up most of the carbon dioxide and utilizes it for photosynthesis as a result it also produces oxygen not only that it also helps to reduce greenhouse effect and helps in maintaining a cooler temperature on earth.
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