Pollution

Total Questions: 50

21. Which of the following air pollutants is most dangerous? [U.P.R.O./A.R.O. (Mains) 2014]

Correct Answer: (d) Carbon monoxide
Solution:The molecular weight of carbon monoxide is similar to that of air. It mixes freely with air in any proportion. Carbon monoxide is not detectable by humans either by taste or smell. In the human body, it reacts with haemoglobin to form carboxyhemoglobin (COHb).

Carbon Monoxide is a colorless, odorless gas created by incomplete combustion of carbon-based fuels such as gasoline, diesel, and wood, as well as the combustion of natural and manmade items like cigarettes. CO is particularly problematic in metropolitan environments, where it contributes to photochemical smog and surface ozone generation through synergistic effects with other pollutants. Ozone concentrations, even at moderate levels, have consequences on the respiratory system.
Carbon monoxide produces carbon dioxide when it burns with a blue flame in the presence of oxygen. Metal manufacture, energy generation, metal ore and coal mining, food production, oil and gas extraction from land or sea, chemical production, cement lime, plaster and concrete manufacturing, and petroleum refining are all examples of industrial operations that produce carbon monoxide.

22. Which one of the following is an air pollutant gas and is released by burning fossil fuel? [U.P.P.C.S. (Mains) 2011]

Correct Answer: (d) Sulphur dioxide
Solution:Sulphur dioxide is an air pollutant gas and is released by burning fossil fuel.
  • Air pollution is largely caused by SO2 emissions. Sulphur Oxides typically occur when there are high levels of SO2 in the air (SOx).
  • Human health is impacted by both direct exposure to it and exposure to PM2.5 (fine particulate matter), which is created when SO2 combines with other air pollutants to form sulphate particles.
  • The burning of fossil fuels in power plants and other industrial facilities is the main contributor to SO2 in the atmosphere.
  • Other sources include industrial procedures like the extraction of metal from ore, natural sources like volcanoes, and heavy machinery like trains and ships that operate on gasoline with a high sulphide content.
  • Particulate Matter can be created by SOx in response to various climatic conditions. Particulate Matter (PM) pollution is increased by these particles.
  • Particulate matter may penetrate the lungs deeply, and too little of it might exacerbate existing health problems.
  • With 91 percent of the population living in areas where open-air pollution exceeds WHO standards, air pollution is now a major concern for overall health (WHO). 4.2 million people pass away annually as a result.
  • The consumption of petroleum derivatives in power plants and other contemporary offices is the best generator of SO2 in the atmosphere.
  • Different sources include industrial operations like mining for metal, natural sources like volcanoes, railways, ships, heavy machinery, and vehicles that use gasoline with a high sulphur content.

23. 'Fly-Ash', is an pollutant which generate by- [U.P.P.C.S. (Mains) 2004]

Correct Answer: (a) Burning of Coal
Solution:Fly ash is an unwanted unburnt residue of coal combustion in a coal thermal power plant. It is emitted along with flue gases during the burning of coal in a furnace and collected using the electrostatic precipitators. The fly ash collected with the help of precipitators is converted into a wet slurry to minimise fugitive dust emissions. It is then transported to the scientifically designed ash ponds through slurry pipelines.
Composition of fly ash depends upon the composition of coal being burnt. It may contain Beryllium, Arsenic, unburnt Carbon, Silicon Oxides, Dioxins, aluminium oxide, ferric oxide, calcium oxide, etc. These elements are severe environmental pollutants

24. Fly ash pollution is caused by: [U.P.P.C.S. (Mains) 2004, U.P.P.C.S. (Pre) 2021]

Correct Answer: (c) Thermal power plant
Solution:Fly ash is a by-product generated as the coal is burnt at thermal power plants. The low-grade coal used in thermal power generation carries 30-45% ash content.

The high-grade imported coal has a low ash content of 10-15% & Notably, since most of the coal used in thermal plants in low-grade, it generates a large quantity of ash which requires a large area as landfill or ponds for disposal.

25. Which one of the following is a bioindicator of air pollution? [U.P.P.C.S.(Pre) 2013, U.P.U.D.A./L.D.A. (Spl) (Pre) 2010]

Correct Answer: (a) Lichen
Solution:Bioindicators are living organisms that respond in a specially clear way to a change in the environment. The hardy lichens are useful bioindicators for air pollution, especially sulphur dioxide pollution since they derive their water and essential nutrients mainly from the atmosphere rather than from the soil.

26. Which of the following is indicator of air pollution? [U.P.P.C.S. (Pre) 2021]

Correct Answer: (c) Lichen
Solution:Lichens are symbiotic associations i.e. mutually useful associations, between algae and fungi. The algal component is known as phycobiont and fungal component as mycobiont, which are autotrophic and heterotrophic, respectively. Algae prepare food for fungi and fungi provide shelter and absorb mineral nutrients and water for its partner. So close is their association that if one saw a lichen in nature one would never imagine that they had two different organisms within them. Lichens are very good pollution indicators - they do not grow in polluted areas.

27. Which one of the following is the well known example of bio-indicator of air pollution? [U.P.P.C.S. (Pre) 2019]

Correct Answer: (a) Lichens
Solution:Lichens are symbiotic associations i.e. mutually useful associations, between algae and fungi. The algal component is known as phycobiont and fungal component as mycobiont, which are autotrophic and heterotrophic, respectively. Algae prepare food for fungi and fungi provide shelter and absorb mineral nutrients and water for its partner. So close is their association that if one saw a lichen in nature one would never imagine that they had two different organisms within them. Lichens are very good pollution indicators - they do not grow in polluted areas.

28. Which of the following Pollution indicator plan? [U.P.P.C.S. (Pre) 2015]

Correct Answer: (c) Lichens
Solution:Lichens are symbiotic associations i.e. mutually useful associations, between algae and fungi. The algal component is known as phycobiont and fungal component as mycobiont, which are autotrophic and heterotrophic, respectively. Algae prepare food for fungi and fungi provide shelter and absorb mineral nutrients and water for its partner. So close is their association that if one saw a lichen in nature one would never imagine that they had two different organisms within them. Lichens are very good pollution indicators - they do not grow in polluted areas.

29. Lichens are the best indicator of- [U.P.P.C.S.(Pre) 2012]

Correct Answer: (a) Air pollution
Solution:Lichens are symbiotic associations i.e. mutually useful associations, between algae and fungi. The algal component is known as phycobiont and fungal component as mycobiont, which are autotrophic and heterotrophic, respectively. Algae prepare food for fungi and fungi provide shelter and absorb mineral nutrients and water for its partner. So close is their association that if one saw a lichen in nature one would never imagine that they had two different organisms within them. Lichens are very good pollution indicators - they do not grow in polluted areas.

30. Which of the following is not a water pollutant? [U.P.P.C.S. (Mains) 2011]

Correct Answer: (d) Sulphur Dioxide
Solution:
  • Air pollution is largely caused by SO2 emissions. Sulphur Oxides typically occur when there are high levels of SO2 in the air (SOx).
  • Human health is impacted by both direct exposure to it and exposure to PM2.5 (fine particulate matter), which is created when SO2 combines with other air pollutants to form sulphate particles.
  • The burning of fossil fuels in power plants and other industrial facilities is the main contributor to SO2 in the atmosphere.
  • Other sources include industrial procedures like the extraction of metal from ore, natural sources like volcanoes, and heavy machinery like trains and ships that operate on gasoline with a high sulphide content.
  • Particulate Matter can be created by SOx in response to various climatic conditions. Particulate Matter (PM) pollution is increased by these particles.
  • Particulate matter may penetrate the lungs deeply, and too little of it might exacerbate existing health problems.
  • With 91 percent of the population living in areas where open-air pollution exceeds WHO standards, air pollution is now a major concern for overall health (WHO). 4.2 million people pass away annually as a result.
  • The consumption of petroleum derivatives in power plants and other contemporary offices is the best generator of SO2 in the atmosphere.
  • Different sources include industrial operations like mining for metal, natural sources like volcanoes, railways, ships, heavy machinery, and vehicles that use gasoline with a high sulphur content.