Answer:
1. Answer: (a) Carbon monoxide
Explanation: Carbon monoxide (CO)—a colorless, odorless, tasteless, and toxic air pollutant—is produced in the incomplete combustion of carbon-containing fuels, such as gasoline, natural gas, oil, coal, and wood.
2. Answer: (b) Nitrogen
Explanation: Nitrogen is not a greenhouse gas because it is not able to absorb infrared radiation and trap heat in the atmosphere.
3. Answer: (d) 1985
Explanation: The works of started with the launching of the Ganga Action Plan (GAP) Phase-I in the year 1985. Subsequently, GAP Phase-II was initiated which included the works on the major tributaries of the river Ganga, namely, Yamuna, Gomti and Damodar.
4. Answer: (b) Infrared radiations
Explanation: The short wavelength (high frequency) infrared radiations come from sun to earth's surface and after reflection from surface , turn into long wavelength infrared radiations , these long wavelength radiations are absorbed by green house gases .
5. Answer: (a) Lead
Explanation: Lead is present in the exhaust of automobiles.The exhaust also contains carbon monoxide and nitrogen oxides.
6. Answer: (d) acid rain
Explanation: Pollutants like sulphur dioxide and nitrogen dioxide in air react with water vapour present in the atmosphere to form sulphuric acid and nitric acid. These acids mix with rain, making it acidic. This acid rain corrodes building material like marble, and the phenomenon is called marble cancer.
7. Answer: (d) aerosols
Explanation: An aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas. Aerosols can be natural or anthropogenic.Colloidal solutions can be classified on the physical state of dispersed phase and dispersion medium. If the dispersion medium is air then the sol is called aerosol.
8. Answer: (a) air pollution
Explanation: The type of pollution which is likely to affect Taj Mahal in Agra to a greater extent is air pollution. It is affecting'Taj Mahal by corroding it and yellowing its marble.
9. Answer: (d) leakage of poisonous gas
Explanation: The Bhopal tragedy, a 1984 chemical spill in Bhopal District, Madhya Pradesh State, India. Approximately 45 tonnes of the toxic gas methyl isocyanate leaked from an insecticide plant operated by the Indian affiliate of the American firm Union Carbide Company on December 3, 1984.
10. Answer: (d) reverse osmosis
Explanation: Water containing high salt concentration can be purified by the process of reverse osmosis. Reverse osmosis is an effective way to remove some unwanted molecules from the water. In the reverse osmosis process, water is let to pass through a membrane, which leads to the separation of water and salt.
11. Answer: (b) DDT
Explanation: DDT, plastics, polythene, lead vapour, silver foils, etc. are non-biodegradable pollutants.
12. Answer: (d) All of the above
Explanation: When a harmful chemical substance, toxic waste, sewage, etc. gets mixed with water the water becomes polluted. It has been found that many industries discharge harmful chemicals into rivers and streams causes water pollution.Untreated sewage and agricultural waste also have similar discharges into water, which results in water pollution.And these are major sources of water pollution.
13. Answer: (c) Drip irrigation
Explanation: In Drip system,water is delivered at or near the roots of plants, drop by drop. This is the most efficient method of irrigation as there is no wastage of water at all.
14. Answer: (c) Reduced oxygen carrying capacity of RBCs
Explanation: This is because when carbon monoxide and oxygen both are available to rbcs then the rbcs will bind 200 times faster with carbon monoxide than oxygen, thus forming carboxyhaemoglobin rather than oxyhaemoglobin.
15. Answer: (b) Smoke + fog
Explanation: A yellowish or blackish fog is named smog. Smoke and fog combine to make smog. It's mainly formed by a mix of pollutants within the atmosphere which consists of fine particles and ground level ozone. Smog occurs mainly due to pollution.
16. Answer: (b) CFCs
Explanation: The gas used in refrigerating appliance causing serious damage to ozone is CFCs.
17. Answer: (d) Sun’s heat is trapped and not allowed to escape
Explanation: Green house effect is a phenomena in which a part of sunlight is trapped by the atmosphere of earth and a part is reflected back to the space. Further, the trapped radiation starts warming the temperature. This is similar to the green house present in a nursery.
18. Answer: (d) Chlorination
Explanation: Chlorination is a commonly used chemical method for purifying water. It kills germs in the water.
19. Answer: (b) Reduce Ganga water pollution
Explanation: The Ganga Action plan was launched in India on 14th January 1986 by Rajiv Gandhi. Its main objective was to protect the river from the hazards of pollution. It aims at improving the quality of its water and preventing further pollution. It acts by preventing the industrial waste from being dumped into the waters.
20. Answer: (d) Planting trees in July
Explanation: Van Mahotsav or Forest Festival is an annual tree-planting festival celebrated in the month of July in which thousands of trees are planted all over the country. Van Mahotsav week is celebrated from 1 July to 7 July to spread awareness of forest conservation and to save the environment.
21. Answer: (c) windmill
Explanation: Windmill will not release any sort of gas into atmosphere hence it is not considered as a source of air pollution.
22. Answer: (a) replace
Explanation: Reduce, reuse and recycle is the formula to conserve natural resource. Replace is not the way to conserve water.
23. Answer: (b) 78%
Explanation:Nitrogen is a colourless, odorless, tasteless and inert gas that accounts for 78 percent of the Earth's atmosphere. So, 78% of Nitrogen is present in the atmosphere.
24. Answer: (c) Tuberculosis and pneumonia
Explanation: Airborne diseases are characterized by diseases that are transmitted through the air via the presence of a pathogen. These pathogens can include both viruses and bacteria that are spread by coughing, sneezing, laughing, or through personal contact. Many types of infections can be a result of airborne transmission- common cold, Pneumonia, Tuberculosis, etc.Cholera and typhoid are waterborne diseases. AIDS is a sexually transmitted disease.
25. Answer: (a) Potable water
Explanation: Water that has a high amount of dissolved salt is called saline water. Water to which air is added is called aerated water. Mineral water contains minerals like magnesium, calcium, sodium, etc. But potable water is the term used for water that is purified and fit to drink.
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