A brief exposure to extremely high sound levels of what magnitude can permanently damage eardrums?
- 100 decibels
- 80 decibels
- 150 decibels
- 120 decibels
Explanation: A brief exposure to extremely high sound level, 150 dB or more generated by take-off of a jet plane or rocket, may damage ear drums.
Which two gases contribute maximum to the total global warming?
- Methane and CFCs
- Ozone and SO2
- CFCs and N2O
- CO2 and Methane
Explanation: Carbon dioxide (60%) and methane (20%) are the two most significant contributors to global warming.
Which of the following is a significant anthropogenic source of methane emissions?
- Rice paddies
- Thermal power plants
- Cement manufacturing
- Automobile exhaust
Explanation: Agricultural activities, particularly flooded rice paddies and livestock digestion, are major anthropogenic sources of methane.
The thickness of the ozone layer in a column of air is measured in:
- Decibels
- Nanometers
- Dobson units
- Micrometers
Explanation: The thickness of the ozone in a column of air from the ground to the top of the atmosphere is measured in Dobson units (DU).
A scrubber in the exhaust of a chemical plant primarily removes which gas?
- Carbon monoxide
- Ozone
- Nitrogen dioxide
- Sulfur dioxide
Explanation: A scrubber is used to remove gases like sulfur dioxide by passing the exhaust through a spray of water or lime.
The 'good' ozone that acts as a shield against UV radiation is found in the:
- Stratosphere
- Ionosphere
- Troposphere
- Exosphere
Explanation: Stratospheric ozone is 'good' ozone because it absorbs harmful ultraviolet radiation from the sun.
The Kyoto Protocol is an international agreement specifically designed to reduce the emission of:
- Heavy metals
- Radioactive waste
- Greenhouse gases
- Ozone depleting substances
Explanation: The Kyoto Protocol commits state parties to reduce greenhouse gas emissions, based on the scientific consensus that global warming is occurring.
What is the main problem associated with the use of CNG in vehicles?
- Low mileage
- Distribution pipeline difficulty
- High adulteration
- Engine knocking
Explanation: The main difficulty with CNG is laying down pipelines for uninterrupted distribution to pumps.
A major domestic and commercial source of ozone-depleting CFCs has historically been:
- Incandescent bulbs
- Heating systems
- Refrigerators
- Water purifiers
Explanation: CFCs were widely used as coolants in refrigerators and air conditioners before the Montreal Protocol phased them out.
Which of the following acts as a primary air pollutant?
- Sulfuric acid
- Sulfur dioxide
- PAN
- Ozone gas
Explanation: Sulfur dioxide is emitted directly from a source (like coal combustion), making it a primary pollutant.
In a catalytic converter, unburnt hydrocarbons are converted into:
- Nitrogen gas
- CO2 and water
- Carbon monoxide
- Methane and ozone
Explanation: The catalytic converter oxidizes unburnt hydrocarbons into carbon dioxide and water.
In which year was the Air Act amended to include noise as an air pollutant?
Explanation: The Air Act of 1981 was amended in 1987 to officially recognize noise as a form of air pollution.
UV-B radiation damages DNA and causes which specific eye disorder?
- Glaucoma
- Color blindness
- Myopia
- Snow blindness
Explanation: High doses of UV-B cause inflammation of the cornea, a condition known as snow blindness or cataract.
In the stratosphere, UV rays act on CFCs to release which active atoms?
- Chlorine atoms
- Hydrogen atoms
- Carbon atoms
- Fluorine atoms
Explanation: UV rays break down CFCs to release active chlorine atoms, which then destroy ozone molecules.
The yellowing and structural degradation of the Taj Mahal is primarily attributed to:
- Global warming
- Smog formation
- Ozone depletion
- Acid rain
Explanation: Acid rain, containing sulfuric and nitric acids, reacts with the marble (calcium carbonate) of the Taj Mahal, causing degradation.
The Montreal Protocol was signed in 1987 to control the emission of:
- Ozone depleting substances
- Greenhouse gases
- Radioactive waste
- Particulate matter
Explanation: The Montreal Protocol is a landmark international treaty designed to phase out the production of numerous substances responsible for ozone depletion.
The severe depletion of the ozone layer over the Antarctic region is called the:
- Ozone depression
- Ozone sink
- Ozone void
- Ozone hole
Explanation: The particularly large area of thinned ozone layer over the Antarctic is referred to as the ozone hole.
Without the natural greenhouse effect, the average temperature of Earth's surface would be:
- Minus 50 degrees
- Zero degrees
- Minus 18 degrees
- Plus 15 degrees
Explanation: Without the greenhouse effect, the average temperature at the surface of Earth would have been a chilly $-18^{\circ}\text{C}$.
Catalytic converters in vehicles are fitted to reduce the emission of:
- Water vapor
- Poisonous gases
- Particulate matter
- Carbon dioxide
Explanation: Catalytic converters reduce the emission of poisonous gases like carbon monoxide and unburnt hydrocarbons.
During winter, thermal inversion traps ground-level air pollutants, commonly resulting in:
- Ozone depletion
- Acid rain
- Severe smog
- Hailstorms
Explanation: Thermal inversion puts a 'lid' over a city, trapping exhaust and pollutants near the ground, causing severe winter smog.
Which device is most widely used to remove particulate matter from thermal power plant exhaust?
- Electrostatic precipitator
- Incinerator
- Scrubber
- Catalytic converter
Explanation: Electrostatic precipitators can remove over 99 percent of particulate matter present in the exhaust from a thermal power plant.
Vehicles fitted with catalytic converters should use unleaded petrol because lead:
- Decreases mileage
- Increases knocking
- Inactivates the catalyst
- Increases smoke
Explanation: Lead present in petrol poisons or inactivates the expensive metal catalysts used in the converter.
Which specific type of ultraviolet radiation is responsible for snow blindness?
- UV-B radiation
- Visible light
- UV-C radiation
- UV-A radiation
Explanation: High doses of UV-B cause inflammation of the cornea, known as snow blindness.
Which of the following is an example of a secondary air pollutant?
- Lead particles
- Sulfur dioxide
- PAN
- Carbon monoxide
Explanation: Peroxyacetyl nitrate (PAN) is a secondary pollutant formed in the atmosphere by the reaction of primary pollutants like NOx and hydrocarbons.
Chlorine atoms degrade ozone and act merely as:
- Precipitates
- Catalysts
- Reactants
- Inhibitors
Explanation: Chlorine atoms act as catalysts in ozone degradation; they are not consumed in the reaction and continuously break down more ozone.
The phenomenon that keeps the Earth's surface warm is naturally called the:
- Ozone shielding
- Thermal inversion
- Greenhouse effect
- Albedo effect
Explanation: The greenhouse effect is a naturally occurring phenomenon responsible for heating Earth's surface and atmosphere.
The severe depletion of the ozone layer is most prominent over the:
- Antarctica region
- Equator region
- Arctic region
- Tropical zones
Explanation: The ozone hole is a large area of thinned ozone layer that develops annually over the Antarctica region.
Which organisms are considered excellent biological indicators of SO2 pollution?
- Fungi colonies
- Lichens
- Mosses
- Green algae
Explanation: Lichens are highly sensitive to sulfur dioxide pollution and do not grow in heavily polluted areas.
The Kyoto Protocol was formally adopted at which Conference of Parties (COP)?
- COP three
- COP one
- COP twenty one
- COP eight
Explanation: The Kyoto Protocol was endorsed at the third Conference of Parties (COP 3) to the UNFCCC in Kyoto, Japan, in 1997.
The ozone hole over Antarctica typically develops each year between:
- Late August
- Early January
- Late December
- Mid March
Explanation: The ozone hole develops each year between late August and early October over Antarctica.
The Earth's stratospheric ozone layer functions primarily to absorb harmful:
- Infrared radiation
- X rays
- UV radiation
- Microwaves
Explanation: The ozone layer absorbs the biologically harmful ultraviolet (UV) radiation emitted from the sun.
Improper burning of hospital and municipal waste in incinerators can release highly toxic:
Explanation: Incineration of waste, especially plastics containing chlorine, can release highly toxic and carcinogenic dioxins.
The Montreal Protocol became officially effective in which year?
Explanation: Although signed in 1987, the Montreal Protocol officially entered into force in 1989.
Global warming is primarily caused by the increase in:
- Sulfur dioxide
- Greenhouse gases
- Ozone concentration
- Suspended particulates
Explanation: The increase in the level of greenhouse gases has led to considerable heating of Earth, leading to global warming.
According to CPCB, what size of particulate matter is most harmful to human health?
- 5.0 micrometers
- 10.0 micrometers
- 2.5 micrometers
- 1.0 millimeter
Explanation: Particulate matter measuring 2.5 micrometers or less in diameter (PM 2.5) can be inhaled deep into the lungs and cause severe health issues.
The Air (Prevention and Control of Pollution) Act came into force in India in:
Explanation: The Air (Prevention and Control of Pollution) Act was enacted in 1981 to control and prevent air pollution in India.
What is the relative contribution of Nitrous Oxide (N2O) to total global warming?
- 60 percent
- 20 percent
- 14 percent
- 6 percent
Explanation: Nitrous oxide accounts for approximately 6% of the greenhouse effect driving global warming.
According to the Indian auto fuel policy outlined in the standard environmental curriculum (NCERT), which phase of Euro norms mandated controlling sulfur at 150 ppm in petrol and 350 ppm in diesel, while containing aromatic hydrocarbons at 42 percent?
- Euro II
- Euro III
- Euro IV
- Euro VI
Explanation: As per NCERT environmental guidelines (the standard reference for UPSC), Euro III norms specifically stipulate that sulfur be controlled at 150 ppm in petrol and 350 ppm in diesel, alongside a 42 percent cap on aromatic hydrocarbons.
The progressive exacerbation of global warming is known to lead to deleterious and odd climatic environmental changes, most prominently observed in the disruption of the:
- El Nino Southern Oscillation (ENSO)
- Milankovitch cycles
- Atlantic Meridional Overturning Circulation
- Stratospheric ozone depletion patterns
Explanation: Global warming leads to deleterious changes in the environment and frequently results in odd, unpredictable climatic shifts, prominently including the exacerbation of the El Nino effect.
A direct consequence of global warming is the melting of polar ice caps, which causes a:
- Thickening of ozone
- Rise in sea level
- Decrease in rainfall
- Drop in temperature
Explanation: Melting of polar ice caps and Himalayan snow caps due to global warming will result in a rise in sea level that can submerge many coastal areas.
Photochemical smog is primarily the result of sunlight acting upon:
- Volcanic ash
- Farm fires
- Automobile exhausts
- Factory effluents
Explanation: Photochemical smog is formed when sunlight reacts with nitrogen oxides and volatile organic compounds, largely from automobile exhausts.
Fine particulate matter (PM 2.5) is considered extremely hazardous to human health primarily because it penetrates deeply into which physiological system?
- The central nervous system
- The gastrointestinal tract
- The integumentary system
- The lower respiratory system
Explanation: PM 2.5 refers to particulate matter 2.5 micrometers or less in diameter. These particles are small enough to bypass the body's natural defenses, being inhaled deep into the lungs and causing severe respiratory issues.
Smog is an extremely harmful air pollutant that is a combination of smoke and:
- Dust particles
- Fog
- Acid rain
- Hail
Explanation: The term smog was coined to describe a mixture of smoke and fog, common in highly polluted industrial cities.
The 'bad' ozone that harms plants and animals is formed in the:
- Thermosphere
- Stratosphere
- Mesosphere
- Troposphere
Explanation: Ozone formed in the lower atmosphere (troposphere) is a harmful pollutant.
The tragic 1984 Bhopal Gas Tragedy was caused by the accidental leakage of:
- Carbon monoxide
- Methyl isocyanate
- Hydrogen cyanide
- Sulfur dioxide
Explanation: The Bhopal Gas Tragedy was caused by a massive leak of toxic Methyl isocyanate (MIC) gas from a pesticide plant.
Which ozone depleting substances are widely used as refrigerants?
- Methane derivatives
- Nitrogen oxides
- Sulfur aerosols
- Chlorofluorocarbons
Explanation: Chlorofluorocarbons (CFCs) are widely used as refrigerants and are a major cause of ozone depletion.
Acid rain is primarily caused by the atmospheric emission of:
- CFCs and Ozone
- SO2 and NOx
- Carbon monoxide
- Methane and dust
Explanation: Sulfur dioxide and nitrogen oxides react with water in the atmosphere to form sulfuric and nitric acids, causing acid rain.
Chronic exposure to relatively lower noise levels in cities can permanently cause:
- Asthma attacks
- Skin cancer
- Hearing loss
- Vision impairment
Explanation: Chronic exposure to a relatively lower noise level of cities may permanently impair hearing abilities of humans.
The intensity of sound or noise pollution is measured in:
- Joules
- Dobson units
- Hertz
- Decibels
Explanation: Noise is measured in decibels (dB), which quantifies the sound pressure level.
High-energy UV-B radiation is highly mutagenic because it causes damage to:
- Lipid bilayers
- Carbohydrate chains
- DNA molecules
- Protein structures
Explanation: UV radiation of wavelengths shorter than UV-B are almost completely absorbed, but UV-B damages DNA and mutation may occur.
Ozone gas is continuously formed by the action of UV rays on:
- Water vapor
- Nitrous oxide
- Carbon dioxide
- Molecular oxygen
Explanation: UV radiation acts on molecular oxygen (O2) to continuously produce and degrade ozone in the stratosphere.
Which metal acts as a catalyst in the catalytic converter of automobiles?
- Zinc and Lead
- Iron and Copper
- Platinum and Palladium
- Gold and Silver
Explanation: Expensive metals like platinum, palladium, and rhodium are used as catalysts in catalytic converters.
Which of the following activities naturally helps in mitigating global warming?
- Livestock farming
- Fossil fuel combustion
- Afforestation
- Deforestation
Explanation: Planting trees (afforestation) helps mitigate global warming because trees absorb CO2 from the atmosphere during photosynthesis.
The major cause of air pollution in metro cities is:
- Burning of garbage
- Automobiles
- Construction dust
- Industrial smokestacks
Explanation: Automobiles are the primary cause of atmospheric pollution in major metropolitan cities.
The 'Green Muffler' scheme is a plantation strategy used to mitigate:
- Water pollution
- Air pollution
- Soil erosion
- Noise pollution
Explanation: Green muffler involves planting rows of trees and shrubs along noisy areas like highways to absorb and reduce noise pollution.
CNG is considered better than diesel because it:
- Weighs much less
- Is extremely cheap
- Is easily available
- Burns more efficiently
Explanation: CNG burns most efficiently, leaving very little unburnt hydrocarbon behind compared to petrol or diesel.
What is the relative contribution of Chlorofluorocarbons (CFCs) to total global warming?
- 20 percent
- 60 percent
- 6 percent
- 14 percent
Explanation: CFCs contribute about 14% to total global warming, making them the third most significant greenhouse gas after CO2 and methane.
Carbon monoxide is highly toxic because it blocks oxygen transport by binding to hemoglobin to form:
- Methemoglobin
- Carbaminohemoglobin
- Carboxyhemoglobin
- Oxyhemoglobin
Explanation: CO has a much higher affinity for hemoglobin than oxygen, forming carboxyhemoglobin and drastically reducing the blood's oxygen-carrying capacity.
In addition to gaseous pollutants, thermal power plants heavily emit fine particulates known as:
- Heavy metals
- Plastic waste
- Fly ash
- Radioactive waste
Explanation: Thermal power plants burning coal generate large amounts of particulate matter in the form of fly ash.
Chronic exposure to UV-B radiation leads to aging of skin and various types of:
- Liver cirrhosis
- Lung cancer
- Kidney failure
- Skin cancer
Explanation: UV-B radiation causes aging of skin, damage to skin cells and various types of skin cancers.