CBSE Class 8 Science Pollution of Air and Water Assignment

<1M>

1.Define air pollution.

2.Which gas is the main constituent of air?

3.Name the green house gases

4.Give two examples of air pollutants.

5.Which two gases cause acid rain?

6.Which phenomenon is responsible for global warming?

7.What is Marble cancer?

8.Which plan was made to save river Ganga?

9.Name two chemical contaminants of water.

10.Which gas is produced due to incomplete combustion of fuels?

11.Name the chemical which is used for the purification of water.

<2M>

12.What is air pollution? Which two diseases are caused due to air pollution?

13.Define potable water? Write the name of any two methods used for the purification of water.

14.What is the Greenhouse effect? How does it affect the atmosphere?

15.What steps has the Supreme Court taken to save the Taj Mahal from air pollution?

16.What is water pollution? Give two examples of water pollutants.

17.What is global warming? Write any one harmful effect of global warming.

18.What is smog? How it is harmful?

19.Why do we need to filter water before drinking? Name any two water borne diseases.

20.List some sources of air pollutants

21.What is green house effect.

22.How does hot water act as pollutant?

<3M>

23.What are the causes of air pollution.

24.What is acid rain? How is it formed?

25.How can you conserve water?

26.Write any three harmful effects of polluted water?

27.What was the Ganga Action Plan? Why it failed in achieving its aim?

28.How does air get polluted?

29.How does the content of carbondioxide rise and become excessive in the atmosphere?

30.Explain the differences between pure air and polluted air.

<5M>

31.What measures should be taken to control air pollution? (any 5 points)

32.Vishal went to Agra after a long period of time. He saw that Taj-Mahal was not as white as earlier. Give the reason for it and explain?

33.What are the sources of water pollution?

34.Discuss how the following contribute to air pollution.
(i) Carbonmonoxide
(ii) Sulphur dioxide
(iii) Chlorafluoro carbons
(iv) Suspend particles

35.Describe the threat to the geauty of the Taj Mahal.

36.Can we reduce air pollution

37.What are the measures that can be taken to control water pollution

Q.1.Choose the correct answer:

a-Which gas is found in largest percentage in air?

i-Oxygen ii-Nitrogen iii-Carbon dioxide iv-Helium

b-What is the source of air pollutant?

i-Industries ii-Power Plants iii-Automobile exhausts iv-All the above

c-Which gas is produced during incomplete combustion of fuels like petrol and diesel?

i-Carbon dioxide ii-Nitrogen iii-Carbon monoxide iv-Sulphur dioxide

d-Refrigerators, air conditioners and aerosol sprays have________pollutant.

i-CFCs ii-CCFs iii-FCCs iv-None of the above

Q.2.Write one word for the following:

a-Very small particles of solids and liquids suspended in air.

b-The gas released during burning of fossil fuels.

c-Two metals which are extremely harmful to the human beings.

d-Name the substance added to the filtered and aerated water to kill harmful germs.

e-The phenomenon of loss of dissolved Oxygen from water in water bodies.

Q.3.Define the following terms:

a- Pollution b- Acid rain c- Global warming d- Green house effect

Q.4. Answer the following questions in 30 words:

a-How do chlorofluorocarbons harm us?

b-Write 3 methods of reducing air pollution?

c-Mention the methods which might be helpful in conserving water.

d-Discuss various processes involved in the purification of water at home.

Q.5. Answer the following questions in 100 words:

a-Describe the greenhouse effect. Name two greenhouse gases.

b-Describe the harmful effects of acid rain.

c-What causes water pollution? How can the water pollution be prevented?

d-What should be the characteristics of potable water?

Q.6.Match the following:

a-Particulate pollutant                     i-Ozone layer

b-Chlorofluorocarbon                      ii-Methane

c-Green house gas                         iii-Jaundice/ Hepatitis

d-Polluted water                              iv-Conservation of water

e-Drip irrigation                               v-Flyash

I. Name the following:

1. Contamination of air

2. The undesirable substance released into the air

3. Process of adding chlorine in water to kill harmful germs.

4. Water which is suitable for drinking water.

5. A poisonous gas which reduces oxygen carrying capacity of the blood.

6. Two fuels used in vehicles to reduce air pollution.

7. Ganga Action Plan was launched in the year.

8. Green house effect is caused due to excessive release of ______________.

9. A hole produced by depiction of ozone in atmosphere.

10. The phenomenon of corrosion of marble of the monuments due to acid rain.

II. Answer the following

1. What is potable water?

2. Name some diseases caused due to water pollution.

3. What is green house effect?

4. Describe methods to purify water.

5. What was the aim of Ganga Action Plan?