Pollution - Questions & Answers

1. Any change in the natural quality of the environment brought about chemical, physical or biological factors:
(a) Pollution
(b) Dust
(c) Humidity
(d) Pollutants
Answer: (a) Pollution

2. The products which are released into the biosphere in large quantities and which affect the normal functioning of ecosystems:
(a) Pollution
(b) Dust
(c) Humidity
(d) Pollutants
Answer: (d) Pollutants

3. Unfavourable alteration of our surroundings, wholly or largely as a by-product of man's actions:
(a) Pollution
(b) Environmental Pollution
(c) Humidity
(d) Pollutants
Answer: (b) Environmental Pollution

4. The alteration in characteristics of water, making it unsuitable for designated use in its natural state:
(a) Air Pollution
(b) Water Pollution
(c) Soil Pollution
(d) Radioactive Pollution
Answer: (b) Water Pollution

5. The pollutants which are formed from the chemical reaction of primary pollutants in the environment:
(a) Biodegradable pollutants
(b) Secondary pollutants
(c) Quantitative pollutants
(d) Non-Biodegradable pollutants
Answer: (b) Secondary pollutants

6. The excessive concentration of foreign matter in the air which adversely affects the well-being of human beings, animals, plants and their environment:
(a) Air Pollution
(b) Pollution
(c) Soil Pollution
(d) Radioactive Pollution
Answer: (a) Air Pollution

7. The pollutants which are not degraded by microbes or degrade at a very slow rate:
(a) Biodegradable pollutants
(b) Primary pollutants
(c) Quantitative pollutants
(d) Non-Biodegradable pollutants
Answer: (d) Non-Biodegradable pollutants

8. Unwanted sound that is an irritant and source of stress:
(a) Air pollution
(b) Radioactive pollution
(c) Noise pollution
(d) Soil pollution
Answer: (c) Noise pollution

9. Which of the following is an example of soil pollution?
(a) Disposal of solid waste in the open
(b) Dumping sewage in the open
(c) Overuse of fertilizers
(d) All of the above.
Answer: (d) All of the above.

10. Nuclear fuels produce pollution by
(a) heat
(b) end products
(c) wastes in coolants
(d) All of the above.
Answer: (d) All of the above.

11. Assertion (A): Eighty per cent of marine pollution comes from land.
Reason (R): Mining for materials such as copper and gold is a major source of contamination in the ocean.
(a) Both A and R are true and R is one of the reasons for A.
(b) Both A and R are true but R does not explain A.
(c) A is true but R is false.
(d) A is false but R is true.
Answer: (b) Both A and R are true but R does not explain A.

Given below are pictures of pollutants, classify them on the basis of degradation.
CONSTRUCTION WASTE, FOOD SERVICE WASTE, GREEN WASTE, PAPER, E-WASTE, GLASS
Answer:
Biodegradable pollutants: FOOD SERVICE WASTE, GREEN WASTE, PAPER
Non-biodegradable pollutants: CONSTRUCTION WASTE, E-WASTE, GLASS

1. What is environmental pollution? What is a pollutant?
Answer: Environmental pollution refers to any unfavourable alteration of our surroundings, wholly or largely as a by-product of man's actions. A pollutant is a substance present in the environment in harmful concentration which contaminates air, water or soil, and adversely affects the environment, human beings and other organisms.

2. Give the difference between natural and man-made pollutants.
Answer: Natural pollutants originate from natural events (like volcanic eruptions), whereas man-made (anthropogenic) pollutants are introduced into the environment directly through human activities, such as industrial pollution, automobiles, and chemical fertilizers.

3. What is air pollution? Give a source of air pollution.
Answer: Air pollution is defined as the excessive concentration of foreign matter in the air which adversely affects the well-being of human beings, animals, plants and their environment. A major source of air pollution includes the combustion of fossil fuels that releases carbon dioxide, sulphur dioxide, and dust into the atmosphere.

4. Define water pollution.
Answer: Water pollution is defined as the alteration in physical, chemical or biological characteristics of water, making it unsuitable for designated use in its natural state.

5. What is soil pollution? Why should we avoid soil pollution?
Answer: Soil pollution is defined as the change in physical, chemical and biological conditions of the soil through man's intervention resulting in degradation in quality and productivity of the soil. We should avoid soil pollution because pollutants can remain in the soil for relatively longer periods, enter the food chain at the plant level, and get magnified as we move up the food chain.

6. What is radioactive pollution?
Answer: Radioactive pollution is defined as the increase in natural background radiation, emerging from the activities of man using naturally occurring or artificially produced radioactive materials.

7. What is noise pollution?
Answer: Noise pollution is defined as an unwanted sound that is an irritant and a source of stress.

1. (a) What are man-made causes of radioactive pollution? Why is radioactive pollution more harmful than other types of pollution?
Answer: Man-made causes of radioactive pollution stem from the use of radioactive materials in the production of nuclear weapons (such as atom bombs) and nuclear fuel in atomic reactors. Radioactive pollution is more harmful than other types of pollution because high-level radioactive wastes remain in the environment for several hundred years, and accidental leakages can cause immediate massive environmental damage and loss of life.

(b) How is noise a source of pollution? Why do we need to look at the problem of noise pollution seriously?
Answer: Noise acts as a source of pollution when loud sounds become unpleasant, serving as a physical irritant and a source of stress directly felt by the receiver. We need to look at this problem seriously because repeated exposure to noise reduces sleeping hours, diminishes human productivity and efficiency, negatively affects peace of mind, and invades personal privacy.

(c) Give a geographical reason for each of the following:
(i) Music is relaxing but playing it loud is a source of pollution.
Answer: A low sound is pleasant and helps with relaxation, but when music is played extremely loud, it crosses the threshold of comfort and becomes an unwanted physical irritant and a source of stress, thus turning into harmful noise pollution.

(ii) Secondary pollutants are toxic.
Answer: Secondary pollutants are formed from the chemical reaction of primary pollutants in the environment, often triggered by sunlight. These chemical reactions create new compounds (like Peroxyacetyl Nitrate and Ozone) that are far more reactive, toxic, and biologically damaging than the original primary pollutants they were derived from.

(iii) Pesticides are qualitative pollutants.
Answer: Pesticides are considered qualitative pollutants because they do not exist naturally in the environment. They are introduced into the soil and water entirely through human agricultural activities.

(d) List the main sources of pollution of ocean waters.
Answer: The main sources of marine pollution are land-based sources (accounting for 80% of marine pollution) which include the spreading of harmful substances like oil, plastic, industrial and agricultural waste. Additional major sources include mining for materials such as copper and gold in the ocean, thermal pollution, oil spills, and nuclear waste disposal.

1. Which type/types of pollution is/are more prominent in the city where you live? List the causes and possible remedies.
Answer: Air and noise pollution are generally the most prominent in modern cities. The main causes include heavy traffic, vehicular emissions, industrial smoke, construction dust, and the frequent use of loudspeakers. Possible remedies include using public transport, shifting to electric vehicles, strict implementation of emission standards for industries, planting trees, and legally restricting the use of loudspeakers and unnecessary honking.

2. Environmental pollution is an incurable disease which can only be prevented. Justify this statement giving examples.
Answer: Environmental pollution causes permanent and often irreversible damage, much like an incurable disease. For example, radioactive wastes remain highly toxic in the environment for hundreds of years and cannot be easily neutralized (e.g., the Chernobyl disaster). Similarly, non-biodegradable pollutants like plastics never fully degrade, and persistent soil pollutants can introduce toxins into the food chain that cause long-term birth defects. Since reversing these deep ecological impacts is practically impossible, the only effective solution is to prevent pollution from occurring through responsible and sustainable practices.

Write down five harmful effects of using non-biodegradable products like plastic bags. Suggest measures that can help to replace plastic bags with eco-friendly products.
Answer:
Five Harmful Effects:
1. They do not naturally degrade and persist in the environment for hundreds of years.
2. They choke drains and sewage systems, leading to urban waterlogging.
3. Animals and marine life often ingest them mistakenly, which can lead to fatal choking or poisoning.
4. Burning plastics releases toxic and harmful gases into the atmosphere, contributing to severe air pollution.
5. They block the natural seepage of rainwater into the ground, degrading soil quality and groundwater recharge.

Suggested Measures:
1. Bring reusable cloth, jute, or canvas bags when going shopping.
2. Encourage shopkeepers to use paper bags for packaging lightweight goods.
3. Implement and enforce strict government bans on single-use plastics.
4. Promote public awareness campaigns about the environmental dangers of non-biodegradable products to encourage the use of eco-friendly alternatives.