Q.1 Which of the following is the primary cause of air pollution in urban areas?
Deforestation
Vehicle emissions
Agricultural runoff
Ozone depletion
Explanation - In urban areas, vehicles are the main contributors to air pollution due to the release of carbon monoxide, nitrogen oxides, and particulate matter.
Correct answer is: Vehicle emissions
Q.2 Acid rain is mainly caused by the presence of which gases in the atmosphere?
Oxygen and Nitrogen
Carbon Dioxide and Methane
Sulfur dioxide and Nitrogen oxides
Hydrogen and Helium
Explanation - Acid rain occurs when sulfur dioxide (SO2) and nitrogen oxides (NOx) react with water in the atmosphere to form sulfuric and nitric acids.
Correct answer is: Sulfur dioxide and Nitrogen oxides
Q.3 Which of the following is a major effect of water pollution on aquatic life?
Increased oxygen levels
Eutrophication
Reduction in sedimentation
Better growth of coral reefs
Explanation - Water pollution from nutrients such as nitrogen and phosphorus leads to eutrophication, causing algal blooms and oxygen depletion, which harm aquatic life.
Correct answer is: Eutrophication
Q.4 Which pollutant is primarily responsible for the formation of smog?
Carbon monoxide
Sulfur dioxide
Nitrogen oxides and VOCs
Ozone in the stratosphere
Explanation - Smog forms when nitrogen oxides and volatile organic compounds (VOCs) react in the presence of sunlight, creating ground-level ozone and haze.
Correct answer is: Nitrogen oxides and VOCs
Q.5 Which is an example of a non-point source of pollution?
A factory discharge pipe
A sewage treatment plant
Runoff from agricultural fields
Oil spill from a tanker
Explanation - Non-point source pollution comes from diffuse sources such as agricultural runoff, which cannot be traced to a single origin.
Correct answer is: Runoff from agricultural fields
Q.6 Which type of pollution is caused by excessive noise in cities?
Air pollution
Water pollution
Noise pollution
Soil pollution
Explanation - Noise pollution refers to harmful levels of sound from traffic, industries, and urban activities, affecting human health and wildlife.
Correct answer is: Noise pollution
Q.7 Which greenhouse gas is most responsible for global warming?
Oxygen
Carbon dioxide
Nitrogen
Argon
Explanation - Carbon dioxide (CO2) traps heat in the atmosphere, leading to global warming and climate change.
Correct answer is: Carbon dioxide
Q.8 Which human activity is a major contributor to soil erosion?
Planting trees
Construction and deforestation
Using organic fertilizers
Rainwater harvesting
Explanation - Deforestation and construction remove vegetation cover, making soil more prone to erosion by wind and water.
Correct answer is: Construction and deforestation
Q.9 Which type of waste is considered hazardous to the environment?
Plastic bags
Organic compost
Industrial chemical waste
Paper waste
Explanation - Hazardous waste contains toxic, corrosive, or reactive substances that pose a threat to human health and the environment.
Correct answer is: Industrial chemical waste
Q.10 What is the main cause of marine pollution?
Oil spills, plastic waste, and chemical runoff
Volcanic eruptions
Wind erosion
Air pollution
Explanation - Marine pollution results from oil spills, dumping of plastics, and chemical runoff from land-based activities.
Correct answer is: Oil spills, plastic waste, and chemical runoff
Q.11 Which layer of the atmosphere is primarily affected by ozone depletion?
Troposphere
Stratosphere
Mesosphere
Thermosphere
Explanation - Ozone depletion occurs in the stratosphere, where harmful UV rays can penetrate due to the reduced ozone layer.
Correct answer is: Stratosphere
Q.12 Which of the following is an effect of air pollution on human health?
Improved vision
Respiratory diseases
Enhanced immunity
Increased bone density
Explanation - Air pollutants such as particulate matter and toxic gases cause respiratory illnesses like asthma, bronchitis, and lung cancer.
Correct answer is: Respiratory diseases
Q.13 Which pollutant is a major contributor to the formation of the 'London-type smog'?
Carbon monoxide
Sulfur dioxide
Nitrogen dioxide
Methane
Explanation - The London-type smog, also called 'classic smog', is caused by sulfur dioxide reacting with fog in cold, humid conditions.
Correct answer is: Sulfur dioxide
Q.14 Which of the following is a renewable source that helps reduce environmental hazards?
Coal
Wind energy
Natural gas
Petroleum
Explanation - Wind energy is renewable and does not emit pollutants, helping reduce environmental hazards associated with fossil fuels.
Correct answer is: Wind energy
Q.15 Which practice can reduce soil pollution?
Excessive use of pesticides
Use of biodegradable fertilizers
Industrial dumping
Burning plastic waste
Explanation - Biodegradable fertilizers reduce chemical residues in soil, preventing soil pollution and maintaining soil health.
Correct answer is: Use of biodegradable fertilizers
Q.16 Which of the following gases is released during incomplete combustion of fuels?
Oxygen
Carbon monoxide
Nitrogen
Methane
Explanation - Incomplete combustion of fuels produces carbon monoxide (CO), a toxic gas that can be lethal in high concentrations.
Correct answer is: Carbon monoxide
Q.17 Thermal pollution is caused primarily by:
Release of heated water from industries
Excessive pesticide use
Vehicle exhaust
Deforestation
Explanation - Thermal pollution occurs when industries discharge heated water into water bodies, affecting aquatic life by reducing oxygen levels.
Correct answer is: Release of heated water from industries
Q.18 Which of the following is an example of indoor air pollution?
Vehicle emissions
Industrial smoke
Smoke from cooking stoves
Volcanic ash
Explanation - Indoor air pollution is caused by smoke and chemicals inside homes, such as emissions from cooking stoves and heating systems.
Correct answer is: Smoke from cooking stoves
Q.19 Which process contributes to groundwater pollution?
Rainwater harvesting
Leaching of chemicals from landfills
Solar energy use
Wind erosion
Explanation - Chemicals from landfills can seep into the soil and contaminate groundwater, posing a risk to drinking water quality.
Correct answer is: Leaching of chemicals from landfills
Q.20 Which of the following is a major environmental hazard caused by mining activities?
Air pollution
Water pollution
Soil degradation
All of the above
Explanation - Mining activities lead to multiple hazards including air and water pollution, soil degradation, and habitat destruction.
Correct answer is: All of the above
Q.21 Which international agreement aims to reduce ozone-depleting substances?
Kyoto Protocol
Montreal Protocol
Paris Agreement
Geneva Convention
Explanation - The Montreal Protocol is an international treaty designed to phase out the production and use of ozone-depleting substances.
Correct answer is: Montreal Protocol
Q.22 Which type of pollution is commonly associated with industrial effluents?
Air pollution
Water pollution
Noise pollution
Light pollution
Explanation - Industrial effluents often contain chemicals and heavy metals that contaminate rivers and lakes, leading to water pollution.
Correct answer is: Water pollution
Q.23 Which of the following is a major source of plastic pollution in oceans?
Agricultural crops
Industrial machinery
Single-use plastics
Sand mining
Explanation - Single-use plastics like bottles and bags accumulate in oceans, harming marine life and ecosystems.
Correct answer is: Single-use plastics
Q.24 Which of these is considered a secondary pollutant?
Sulfur dioxide
Carbon monoxide
Ozone at ground level
Methane
Explanation - Secondary pollutants are formed by reactions of primary pollutants in the atmosphere. Ground-level ozone forms when NOx and VOCs react in sunlight.
Correct answer is: Ozone at ground level
Q.25 Which practice contributes to reducing urban air pollution?
Promoting public transportation
Deforestation
Burning fossil fuels
Unregulated industrial expansion
Explanation - Using public transport reduces the number of vehicles on the road, decreasing emissions and improving urban air quality.
Correct answer is: Promoting public transportation