Class 8 Science Chapter 9 – Pollution of Air and Water – All Textual Solutions | ASSEB Assam (English Medium)
Class 8 Science Chapter 9 – Pollution of Air and Water Complete Textual Questions and Answers (ASSEB / SEBA Assam – English Medium)
Chapter 9 of the Class 8 Science curriculum, ‘Pollution of Air and Water’, is an extremely vital environmental science lesson for students. These complete textual question-answer solutions (Class 8 Science Chapter 9 Textual Solutions) have been meticulously prepared based on the latest guidelines of the new ASSEB (Assam State School Education Board) syllabus and the National Education Policy (NEP). This comprehensive compilation includes textbook-based Very Short Answers (VSA), Short Questions, Long Answers, detailed explanations, and key environmental definitions. Ospin Academy provides these solutions in a simple, accurate, and completely exam-oriented format.
The chapter ‘Pollution of Air and Water’ provides an in-depth understanding of the harmful alterations occurring in our natural surroundings due to human activities. It explores major air pollutants (carbon monoxide, smog, chlorofluorocarbons), the phenomena of acid rain and the greenhouse effect, global warming, and the specific case study of the Taj Mahal (marble cancer). Additionally, the chapter covers water pollution, the contamination of rivers like the Ganga, potable water standards, and various methods of water purification. It is essential for students to thoroughly grasp these core concepts. Our textual solutions not only cover all the standard textbook exercises but also include important additional exam-oriented questions to ensure robust preparation.
What you will learn and get from these textual solutions:
- Clear explanations of the causes and severe effects of air and water pollution on human health and the environment.
- Accurate, point-wise answers for 1-mark objective questions (VSA) and 2-3 mark short textual questions regarding greenhouse gases and pollutants.
- Standard and easy-to-understand explanations for descriptive questions, such as the mechanism of the greenhouse effect and methods to make water safe for drinking.
- Complete coverage of end-of-chapter exercises, fill-in-the-blanks, give-reason sets, and individual steps that can be taken to reduce pollution.
- Extra important questions aligned with the new syllabus structure alongside standard MCQ solutions.
Exclusive features of Ospin Academy’s solutions:
- Fully textbook-based answers formulated strictly according to the latest ASSEB new syllabus guidelines.
- 100% accurate, high-quality notes written in simple English language for effortless memorization and environmental awareness.
- Concise summaries and targeted answers specifically designed for quick revision before examinations.
- A curated selection of highly probable extra questions to give students a competitive edge.
Committed to the academic excellence of students, Ospin Academy offers these high-quality textual solutions. Start your preparation today to master the concepts of Science and achieve top scores in your upcoming examinations.
Class 8 Science (English Medium) PDF Solutions 2026-27 | SCERT Assam
Get the Class 8 Science (English Medium) PDF with detailed solutions, MCQs, and extra practice questions for SCERT Assam 2025-26.
Class 8 Science
Chapter – 9 Ospin Academy
Pollution of Air and Water
TEXTBOOK EXERCISES
Q. 1. What are the different ways in which water gets contaminated?
Ans. Water gets contaminated by following ways:
(i) Water gets contaminated when sewage is disposed off in rivers.
(ii) Chemicals which are harmful and poisonous are thrown in water resources by various industrial units.
(iii) Harmful chemicals used in agricultural process gets mixed with ground water making it unfit for consumption.
(iv) Breeding of microorganisms in water make water polluted.
Q. 2. At an individual level, how can you help reduce air pollution?
Ans. We can plant tree to reduce the level of carbon dioxide. We can get our vehicles serviced well to reduce incomplete consumption of fuels. We can also reduce air pollution by saying no to crackers during Diwali celebrations.
Q. 3. Clear, transparent water is always fit for drinking. Comment.
Ans. The clear, transparent water may not always safe for drinking because it may still contain harmful microorganisms.
Q. 4. You are a member of the municipal body of your town. Make a list of measures that would help your town to ensure the supply of clean water to all its residents.
Ans. (i) To get clean water in every household, it is necessary that water reaching houses should be treated water. Water is treated in sewage plants, to make it free from physical, chemical and biological impurities.
(ii) Strict laws should be enforced on industrial units, which dispose polluted water in water resources.
(iii) Open defecation in water resources by slum dwellers should be strictly prohibited.
(iv) Chlorine tablets should be distributed for purification of water during rainy season.
(v) People should be made aware and motivated to keep water resources clean.
Q. 5. Explain the differences between pure air and polluted air.
Ans. Pure air is free from harmful gases which can be poisonous in nature. Pure air has balanced quantity of all its constituent gases. It is free from other germs. This type of air is fit for breathing. On the other hand polluted air has poisonous gases and other suspended impurities like dust and smoke. It is unfit for consumption.
Q. 6. Explain circumstances leading to acid rain. How does acid rain affect us?
Ans. Some pollutants like sulphur dioxide and nitrogen dioxide reacts with the water vapour present in the atmosphere to form sulphuric acid and nitric acid . The acid drop down with rain, making the rain acidic. This is called acid rain. Acid rain affects us in many ways.
(i) Acid rain corrodes the marble of the monument.
(ii) Acid rain damages building and sculptural materials.
(iii) Acid rain damages fresh water also.
(iv) Acid rain also damages our crops and also makes it poisonous.
(v) Acid rain damages the leaves of plants.
Q. 7. Which of the following is not a greenhouse gas?
(a) Carbon dioxide.
(b) Sulphur dioxide.
(c) Methane.
(d) Nitrogen.
Ans. (b) Sulphur dioxide.
Q. 8. Describe the ‘Green House Effect’ in your own words.
Ans. Greenhouse effect means warming the environment. When the rays of sun reach earth, some of the heat is absorbed by the earth. Rest of it is reflected back by the earth. Some of the heat is trapped by the environment of the earth. This causes warming of the environment, which is necessary for the sustaining life. This trapping of the heat is called greenhouse effect.
Q. 9. Prepare a brief speech on global warming. You have to deliver the speech in your class.
Ans. Continuous increase in the temperature of the earth is called global warming. It is caused by the pollution of air, excessive heat trapped by the greenhouse gases, because the amount of green house gases has increased in the environment. Global warming is a threating phenomenon because we may have to face dire consequences due to Global warming.
Q. 10. Describe the threat to the beauty of the Taj Mahal.
Ans. Increasing air pollution has posed a threat to the beauty of the Taj Mahal. Excessive poisonous gases and smoke has started to discolour the white marble of the Taj Mahal. Acid rains due to increasing air pollution has started to corrode the marble, thus making Taj Mahal loose its beauty.
Q. 11. Why does the increased level of nutrients in the water affect the survival of aquatic organisms?
Ans. Excessive quantities which get washed from the fields, act as nutrients for algae to flourish. Once these algae die, they serve as food for decomposers like bacteria. A lot of oxygen in water body get used up. This results in a decrease in the oxygen level which may kill aquatic organisms.
