MCQ Questions for Class 8 Science: Ch 18 Pollution of Air and Water
1. The increase in concentration of which gas is not responsible for Global Warming?
(a) Sulphur dioxide
(b) Nitrogen
(c) Carbon dioxide
(d) Methane
► (b) Nitrogen
2. Last stage in treatment of sewage is
(a) Sterilization
(b) Evaporate
(c) Chlorination
(d) Aeration
► (c) Chlorination
3. Identify the gas associated with greenhouse effect.
(a) Carbon dioxide
(b) Oxygen
(c) Nitrogen dioxide
(d) Sulphur dioxide
► (a) Carbon dioxide
4. Which of the following is not a green house gas?
(a) Water vapour
(b) Nitrogen gas
(c) Methane gas
(d) Carbon dioxide
► (b) Nitrogen gas
5. Sea water is unfit for drinking because it contains
(a) Dead plants and animals
(b) Dissolved organic matter
(c) Rain water
(d) Large amount of salt
► (d) Large amount of salt
6. Which one is not an organic waste?
(a) DDT
(b) Paper
(c) Cotton cloths
(d) Vegetable peels
► (a) DDT
7. CNG is a
(a) polluted fuel
(b) pollution free fuel
(c) harmful fuel
(d) None
► (b) pollution free fuel
8. Most polluted river in the world is:
(a) Yamuna
(b) Cavery
(c) Chenab
(d) Ganga
► (d) Ganga
9. Addition of harmful substance in water to make it unfit for human consumption is called
(a) Water pollution
(b) Biomagnifications
(c) Decomposition
(d) Retardation
► (a) Water pollution
10. Trees help in reducing the pollution of our environment. Lakhs of trees are planted by people in the month of July every year. The occasion is called
(a) Forest Conservation Day
(b) Van Mahotsav
(c) Plantation month
(d) Wildlife week
► (b) Van Mahotsav
11. Air pollution causes
(a) Global warming
(b) Respiratory diseases
(c) Soil erosion
(d) None of these
► (b) Respiratory diseases
12. The Taj Mahal is being affected due to:
(a) Noise pollution
(b) Air pollution
(c) Water pollution
(d) None of these
► (b) Air pollution
13. Heat is reflected from the earth's surface and trapped in the atmosphere. Which phenomena is being referred to?
(a) Global warming
(b) Ozone depletion
(c) Greenhouse effect
(d) Thermal pollution
► (c) Greenhouse effect
14. Green house gas is
(a) Nitrogen
(b) Oxygen
(c) Methene
(d) Carbon dioxide
► (d) Carbon dioxide
15. Which of the following does NOT cause air pollution?
(a) Increasing forest reserves
(b) Using pesticides in farms
(c) Developing housing estates
(d) Quarrying for limestone
► (a) Increasing forest reserves
16. The phenomenon of marble cancer is due to
(a) Soot particles
(b) CFCs
(c) Acid rain
(d) Fog
► (c) Acid rain
17. Which one is a common source of drinking water?
(a) Spring water
(b) Ocean water
(c) Sea water
(d) River and lake
► (d) River and lake
18. The water that is purified and fit for drinking is called
(a) Potable water
(b) Pure water
(c) Hard water
(d) Saline water
► (a) Potable water
19. Finer hair inside the nose
(a) Filter the microbes
(b) Prevent the water vapour
(c) Filter the dust particle
(d) Prevent the carbon dioxide gas
► (c) Filter the dust particle
20. The substance that pollute the natural substance is called
(a) Magnifier
(b) Fertilizers
(c) Pollutant
(d) Reactant
► (c) Pollutant
21. How are monuments of marble destroyed?
(a) By sulphur dioxide pollution.
(b) By carbon monoxide pollution.
(c) By pesticide pollution.
(d) By dust particles.
► (a) By sulphur dioxide pollution.
22. Which of these is the major air pollutant in cities like Delhi and Kolkata?
(a) Carbon monoxide
(b) Hydrocarbons
(c) Suspended particulate matter
(d) Oxides of nitrogen
► (c) Suspended particulate matter
23. How are lead particles released into the air?
(a) By burning coal in thermal power stations
(b) By burning petrol in automobiles
(c) By burning biomass in chullahs
(d) By burning LPG for cooking
► (b) By burning petrol in automobiles
24. From which of the following bad effects does the ozone layer in our atmosphere protect us?
(a) Carbon dioxide
(b) CFC's
(c) The sun's ultraviolet rays
(d) All of the above
► (c) The sun's ultraviolet rays
25. Chlorofluorocarbon is used in
(a) Refrigerators
(b) Air conditioners
(c) Aerosol sprays
(d) All
► (d) All