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Pollution of Air and Water for class 8th


Fill in the blanks on Pollution of Air and Water for class 8th (VIII)1. The contamination of air by unwanted substances which have a harmful effect on both the living and the non-living is called -----------.

Ans: Air pollution.
2. The substances which contaminate the air and water are called -----        
Ans: Pollutants

3. The rise in Earth’s temperature is called_______________.

Ans: global warming 

4. ______________accumulates in body fat and travels up the food chain.

Fertilizers

5. _________________results in the death of birds & aquatic animals.

Ans: oil spills

6. ____________________depletes the ozone layer.

Ans: CFCs

7. _________________is a clean fuel.

Ans: CNG 

8. Water fit for drinking is called_________________.

Ans: potable water

9. ________________is celebrated in the month of July every year

Ans:  van mahotsav

10. ____________________causes acid rain. 

Ans: sulphur dioxide 

11. _______________________causes excessive growth of algae in water bodies.

Ans: DDT
MCQs on Pollution of Air and Water for class 8th (VIII)

Select the correct answer. There can be more than one correct answer.

1. Natural sources of air pollution are:

A. Forest fires

B. Volcanic eruptions

C. Dust storm

D. Smoke from burning dry leaves

2. Use of excessive fertilizer in fields leads to the deficiency of _______in the nearby water body.

A. Carbon dioxide

B. Carbon monoxide

C. Nitrogen

D. Oxygen

3. Acid rain is due to   

A. Combustion of fossil fuels

B. Oil slick

C. Oxides of sulphur

D. Nuclear warheads

4. Pollution is not caused by the use of:

A. Solar energy 

B. Wood

C. Fossil fuel

D. Unsaturated hydrocarbons

5. Refrigerators and air conditioners have one of the following gas:

A. Hydrochloric acid

B. Methane

C. Chlorofluorocarbons 

D. Sulphuric acid

6. Which of the following is greenhouse gas?

A. CO2

B. H2O

C. CH4

D. S02

7. The effect of pollution is first and most marked on

A. Natural flora of a place

B. Air quality

C. Natural geochemical cycles 

D. All the above

8. Which of the following is of maximum threat to human being?

A. Depleting forest

B. High population and pollution

C. Spread of Aids  

D. Urbanization

9. Which of the following are environments - friendly practices?

A. Carrying cloth bags for shopping

B. Using alternate source of energy

C. Switching off unnecessary lights and fans

D. Covering short distances by walk

10. D.D.T. is

A. Non-biodegradable pollutant

B. Bio-degradable pollutant

C. Fertilizer

D. None of these

11. Ozone hole is largest over

A. Antarctica

B. USA

C. Europe

D. India

12. Carbon monoxide is a pollutant because it

A. AbsorbsC02

B. Reacts with hemoglobin

C. Causes burning of eyes

D. Inhabits photosynthesis

13. Fertilizer washed into rivers can cause excessive growth of 

A. Microorganism

B. Algae

C. Fungi

D. Sea snakes

14. Smog is mixture of which sunstance

A. smoke and fog

B. sulphur dioxide and nitrogen dioxide.

C. oxygen and nitrogen

D. Dust and Fog

15.When  Ganga Action Plan was launched to save Ganga River

A. 1995

B. 1985

C. 1895

D. 1958

Answer the following questions in brief.

1. How do polythene bags harm the environment?

Ans:  polythene bags get into soil and slowly release toxic chemicals. They eventually break down into the soil, with the unfortunate consequence being that animals eat them and often choke and die.

2. How does land pollution lead to water pollution?

Ans: When land gets polluted and rain occur all its pollutant dissolve in water and are washed into water bodies that causes water pollution.

3. What problems do you fore see in overpopulated cities?

4. What would happen if chlorinated water of a swimming pool was regularly discharged into the local River?

Ans: it can kill aquatic life
5.  Can you think of some ways by which we can neutralize the harmful effects of pollution?  

Ans: We can plant trees. We use public transport. We use alternative source of energy like solar energy, hydropower and wind energy. The sewage treatment plant help to clean sewage

Upcoming: HOTS Questions

1.  Is it possible to have a food chain without CO? Then why is increase in CO2 percentage becoming a serious global issue?

2. Water pollution is a form of local pollution. Do you agree with the statement?

3. Can pollution lead to extinction of a particular species of animal?

Comments

  1. Nice posting, thanks for sharing with us. Your blog is great and helped me feel better knowing about the pollution of air and water chapter of class 8. Thanks again!

    ReplyDelete

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