Pollution MCQ Quiz in मल्याळम - Objective Question with Answer for Pollution - സൗജന്യ PDF ഡൗൺലോഡ് ചെയ്യുക

Concept:

Air pollutants:

• Pollutants are classified in different ways.
• According to origin pollutants are two types.

Explanation:

Primary pollutants:

• These are directly emitted from the sources in the atmosphere in a harmful form.
• They can be natural (volcanic eruptions or fires, for example) or of anthropogenic origin (carbon monoxide from vehicles).

Secondary Pollutants:

• These are derived from primary pollutants due to chemical or photochemical reactions in the atmosphere they become hazardous after reaction in the air. 
• The best-known secondary pollutants are certain gases that are synthesized by photochemical reactions in the lower atmosphere.
• The primary emitted chemicals in these reactions are hydrocarbons and gaseous oxides of nitrogen such as nitric oxide and nitrogen dioxide. 
• Its origin lies in the interactions between the primary emissions in the atmosphere.

Important Points 

Examples of primary and secondary air pollutants:

Thus, ozone is called a secondary air pollutant.

The correct answer is Lead.

Key Points

• Lead:
  • Lead is a common metal pollutant from automobile exhausts.
  • Lead is a potent neurotoxin, particularly harmful to children and pregnant women, damaging the nervous system and cognitive development.
  • Its effects can be irreversible and life-altering.
  • ​Though phased out of gasoline in many countries, lead exposure from older vehicles or contaminated soil can still be a concern.

Additional Information

• Mercury:
  • ​Mercury in the atmosphere is only a small part of the overall mercury burden of the environment.
  • It is present in gaseous form in the atmosphere because of its relatively high vapour pressure.
  • The gaseous mercury is washed from the air by rain; a portion of it enters the aquatic systems and the remaining is bound to the soil over the land.
  • The physiological effects of mercury poisoning include neurological damage, chromosomal aberrations, and even death.
• ​Cadmium:
  • Cadmium is a potential health hazard due to its presence in the urban atmosphere and cigarette smoke.
  • Cigarette smoking constitutes a major source of cadmium accumulation in the body.
  • Cadmium inhibits the performance of certain enzymes thereby producing hypertension in humans.
  • Exposure to fumes or oxides of cadmium is known to cause cardiovascular diseases.

Air pollution can have detrimental effects on famous heritage monuments and cultural landmarks around the world. The impact of air pollution on these structures is a complex and ongoing concern.

Key Points Here are some ways in which air pollution can affect heritage monuments:

1. Deterioration of Building Materials:

   • Acid Rain: Air pollution, particularly sulfur dioxide (SO2) and nitrogen oxides (NOx) emissions, can lead to the formation of acid rain. Acid rain can accelerate the deterioration of building materials, causing corrosion and erosion of surfaces over time.

2. Surface Soiling and Discoloration:

   • Particulate Matter: Fine particulate matter (PM) in the air, such as soot and dust, can settle on the surfaces of monuments, leading to soiling and discoloration. This can affect the aesthetic appearance of the structures.

3. Chemical Reactions:

   • Oxidation: Certain pollutants in the air can contribute to oxidation reactions on the surfaces of monuments. This chemical reaction can result in the formation of compounds that may alter the color and composition of the building materials.

4. Biological Growth:

   • Microbial Growth: Airborne pollutants can provide nutrients for microbial growth on monument surfaces. Algae, lichens, and fungi may thrive in polluted environments, causing further damage and discoloration.

5. Weakening of Stone and Metal:

   • Ozone Exposure: Ground-level ozone, a component of photochemical smog, can accelerate the weathering of certain materials, including stone and metals, by breaking down their molecular structures.

6. Loss of Details and Features:

   • Abrasion: Windborne abrasive particles in the air, including dust and sand, can lead to physical abrasion of monument surfaces, resulting in the loss of fine details and features.

7. Corrosion of Metals:

   • Corrosive Gases: Airborne pollutants, especially sulfur dioxide, can lead to the corrosion of metals present in monuments. This is a significant concern for structures with metal components or decorations.

8. Increased Maintenance Costs:

   • Cleaning and Restoration: The impact of air pollution often necessitates more frequent and intensive cleaning and restoration efforts to preserve the appearance and structural integrity of heritage monuments. This can lead to increased maintenance costs.

Additional InformationEfforts to mitigate the impact of air pollution on heritage monuments include air quality management measures, emission reduction policies, and the implementation of protective coatings on monument surfaces. Additionally, promoting sustainable practices and reducing overall pollution levels contribute to the long-term preservation of cultural landmarks.

The correct answer is non-biodegradable pollutants.

Key Points

• DDT and aluminum cans are both resistant to decomposition by natural processes, meaning they can persist in the environment for long periods of time and cause pollution.
• DDT is a persistent organic pollutant (POP) that was once widely used as an insecticide. However, it was banned in many countries due to its harmful effects on the environment and human health.
• Aluminum cans, while recyclable, take hundreds of years to decompose naturally if littered or landfilled.

Additional Information

• Primary Pollutants: Primary pollutants are directly emitted into the atmosphere from sources such as vehicles, industries, and natural processes.

  • Examples: Carbon Monoxide (CO), Sulfur Dioxide (SO₂), Particulate Matter (PM)

• Secondary Pollutants: Secondary pollutants are not directly emitted but form in the atmosphere through chemical reactions between primary pollutants and atmospheric compounds.

  • Examples: Ground-Level Ozone (O₃), Sulfuric Acid (H₂SO₄)

• Biodegradable Pollutants: Biodegradable pollutants are substances that can be broken down or decomposed by natural processes, such as microbial action or exposure to sunlight.

  • Examples: Organic Waste, Biodegradable Plastics, Sewage

The correct answer is - It estimates air pollution mainly sulphur content in the air

Key Points

• Air Quality Index (AQI)
  • The AQI is a measure used to indicate the level of air pollution in a specific area.
  • It helps the public understand how polluted the air currently is or how polluted it is forecasted to become.
  • AQI primarily includes measurements of pollutants such as particulate matter (PM10 and PM2.5), ground-level ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide.
  • Among these pollutants, the estimation of sulfur content is crucial as sulfur dioxide (SO2) can lead to respiratory problems and other health issues.

Additional Information

• Pollutants measured by AQI
  • Particulate Matter (PM10 and PM2.5)
    • These are tiny particles that can penetrate deep into the lungs and even enter the bloodstream, causing various health issues.
  • Ground-level Ozone (O3)
    • Ozone at ground level is a harmful air pollutant. It can cause breathing difficulties and aggravate asthma.
  • Carbon Monoxide (CO)
    • Carbon monoxide is a colorless, odorless gas that can be harmful when inhaled in large amounts. It prevents the blood from carrying oxygen to cells, tissues, and organs.
  • Sulfur Dioxide (SO2)
    • Sulfur dioxide can cause respiratory problems and is a key component of acid rain.
  • Nitrogen Dioxide (NO2)
    • Nitrogen dioxide is another pollutant that can irritate the airways in the human respiratory system.
• Health Effects of Air Pollution
  • Exposure to high levels of air pollution can lead to various health issues such as respiratory infections, heart disease, and lung cancer.
  • Children, the elderly, and individuals with preexisting health conditions are more susceptible to the adverse effects of air pollution.
• Preventive Measures
  • Using public transportation, reducing industrial emissions, and implementing stricter environmental regulations can help reduce air pollution levels.
  • Individuals can also take personal measures such as wearing masks, using air purifiers, and avoiding outdoor activities during high pollution days.

The correct answer is option 4.

Key Points

• Particulate matter refers to tiny particles suspended in the air which have diameter of 2.5 microns(2.5*10^-6 m) or less are called PM_2.5.
• These are visible only with the help of an electron microscope.
• These are so small that they can easily enter the lungs and subsequently into blood.
• Once inhaled they can cause respiratory and heart problems.
• Sources: burning of fossil fuels like coal, wood and forest fires.

Additional Information

• PM 10 are the particles suspended in that have a diameter less than 10 microns.
• Following figure shows the comparison of sand particle, PM_2.5 and PM₁₀

Concepts:

Non-renewable energy is obtained from nature and limited in nature and can not renew once gets depleted

• Example- fossil fuel energy, such as coal, crude oil, and natural gas which 

Renewable energy is also known as clean energy which is obtained from natural sources and can be replenished.

• Example- Solar energy, wind energy, hydroelectric power, biomass energy, geothermal energy, and tidal energy are examples of renewable sources of energy.

Explanation:

Natural gas

• when the natural gas is burned, it produces mostly carbon dioxide and water vapour 
• the same substances emitted when humans exhale.
• Compared with some other fossil fuels, natural gas emits the least amount of carbon dioxide into the air when combusted
• making natural gas the cleanest burning fossil fuel of all.

hence Natural gas is a less polluting fuel

Concept:

Pollution:

• Pollution is any undesirable change in physical, chemical or biological characteristics of air, land, water or soil.

Water pollution:

• Whenever harmful substances such as sewage, toxic chemicals, silt, etc, get mixed with water, the water becomes polluted.
• The substances that pollute water are called water pollutants.

Explanation:

Humus matter:

• Humification leads to the accumulation of a dark-coloured amorphous substance called humus.
• That is highly resistant to microbial action and undergoes decomposition at an extremely slow rate.
• Being colloidal in nature it serves as a reservoir of nutrients.
• The humus is further degraded by some microbes and the release of inorganic nutrients occurs through the process known as mineralisation.
• Crops such as wheat are grown in fine clayey soils because they are rich in humus and are very fertile.

Thus, humus matter is not a human source of water pollution. 

 Additional InformationSewage: 

• It is wastewater released by homes, industries, hospitals, offices and other users.
• It also includes rainwater that has run down the street during a storm or heavy rain.
• The water that washes off roads and rooftops carries harmful substances with it.
• Sewage is liquid waste including domestic and industrial wastewater that pollute water sources.

Concept:

• Along with harming human health, air pollution can cause a variety of environmental effects that affect the overall environment, acid rain being one of them.

Explanation:

Acid Rain:  

• Acid rain means the precipitation of acidic components such as Sulfuric or Nitric acid.
• Sulfur dioxide and oxides of nitrogen get into the upper atmosphere by wind or air currents and get mixed with water.
• The SO2 and NOX react with water, oxygen and other chemicals to form sulfuric and nitric acids.
• Normal rain has a pH value of 5.6.
• It is slightly acidic due to the presence of carbon dioxide which gets dissolved into the water forming weak carbonic acid.
• In acid rain, SO₂ contribute 70% and NO₂ contributes 30% in terms of concentration. 
• However, acid rain usually has a pH between 4.2 and 4.4 because of the large quantity of acids. 
• The major sources of sulphuric dioxide and oxides of nitrogen are the burning of fossil fuels, emissions from vehicles, oil refineries, etc. 

Thus, in acid rain SO2 accounts for 70%.

Important Points

Sources of SOx:

• Seas and oceans
• Volcanic eruptions
• Biological processes in the soil
• Burning of coal
• Petroleum product
• Industries

Sources of NOx:

• Lightening
• Volcanic eruptions
• Biological activity
• Forest fires
• Combustion of oil and coal

Additional Information

​Controlling Acid rain: 

• Reducing the amount of SO2 and NO2 being released into the atmosphere decreases the chances of acid rain.
• The main source of SO2 is coal fuel power plants in which SO2 emission can be reduced by new combustion techniques.
• Whereas the main source of NO2 in the atmosphere is through vehicular exhaust which can be controlled by using internal combustion engines.
• Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are related to the air.
• These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.

The solution is to increase when sewage gets mixed with river water.

Concept

• Biochemical Oxygen Demand (BOD) is the amount of oxygen required by bacteria to break down the organic matter present in a certain volume of a sample of water.
• The amount of BOD in the water is a measure of the amount of organic material in the water, in terms of how much oxygen will be required to break it down biologically.

Explanation

• Sewage is wastewater released by homes, hospitals, offices, and other domestic sources and contains a variety of organic dissolved and suspended impurities and organic materials like food and vegetable waste.
• When sewage enters the river water, microorganisms begin to decompose the materials. 
• As sewage is rich in an organic matter a very high amount of oxygen is needed to bring about the decomposition of sewage(there is an increase in the BOD value of the river water)
• As a result, all the dissolved oxygen in the water is used up  because those microorganisms use it in their metabolism (there is a sharp decline in dissolved oxygen downstream from the point of sewage discharge)
• Effect of  Sewage on the BOD OF  river water illustrated below

Thus, Biochemical Oxygen Demand (BOD) in river water Increases when sewage gets mixed with river water.

Additional Information

Algal Bloom:

• The presence of large amounts of nutrients in water causes excessive growth of planktonic (free-floating) algae, called an algal bloom. 
• It imparts a distinct colour to the water bodies.
• Increases the Biochemical oxygen demand (BOD) as they produce toxins causing anoxic conditions and death of the lakes. 

• Algal blooms cause deterioration of the water quality and fish mortality.