NCERT Solutions Class 8 Science Chapter 18 Pollution Of Air And Water
NCERT Solutions Class 8 Science Chapter 18 Pollution Of Air And Water: National Council of Educational Research and Training Class 8 Science Chapter 18 Solutions – Pollution Of Air And Water. NCERT Solutions Class 8 Science Chapter 18 PDF Download.
NCERT Solutions Class 8 Science Chapter 18: Overview
Board |
NCERT |
Class |
8 |
Subject |
Science |
Chapter |
18 |
Chapter Name |
Pollution Of Air And Water |
Topic |
Exercise Solutions |
NCERT Solutions Class 8 Science Chapter 18 – Pollution Of Air And Water
CHAPTER: – 18 (POLLUTION OF AIR AND WATER)
Exercise: –
1)What are the different ways in which water gets contaminated?
Ans: – The ways by which water get contaminated
- By the industrial waste.
- Waste of drainage.
- Chemical waste from field.
- Unused substance gets dumped in water.
2)At an individual level, how can you help reduce air pollution?
Ans: – The ways for the reduce the air pollution is
- Tree plantation is most useful.
- Takes necessary steps for the reduction of deforestation.
- Try to reduce the release of toxicity air from different factory if possible used chimney at the liberating point.
3)Clear, transparent water is always fit for drinking. Comment.
Ans: – A clear, transparent water not always fit for drinking as there may be microbes which can affect our body. We should always purify any water before drinking which also hygienic for our health as well as helps in digestion and free minded.
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: – The ways which will be beneficial for the town for the cleaning of the water to all residence will be
- There should be proper cover of the water tank storage.
- Nearest water storing pond or other places outside area should be clean.
- Always try to restore the rain water.
- Apply some disinfectant in the water in time gap to the water storage.
5)Explain the differences between pure air and polluted air.
Ans: – The main difference between the pure air and polluted air is the polluted air contain the different harmful gases but the pure air not. The pure air is necessary for the respiratory activity in our body but the polluted air damage the lungs.
6) Explain circumstances leading to acid rain. How does acid rain affect us?
Ans: – The acid rain is very dangerous for our health as this rain is created dangerous effect in the environment such as the different monument present in that specific area as well as the water-logged area also. The sulphur dioxide after reacting with the water makes the acid rain.
7)Which of the following is not a greenhouse gas?
(a) Carbon dioxide
(b) Sulphur dioxide.
(c) Methane
(d Nitrogen.
Ans: – Here option(d)
Explanation- nitrogen is not a greenhouse gas. The gases which affect the ozone layer that gas is known as greenhouse gases. Like methane, CFC, CO2 etc.
8)Describe the ‘Green House Effect’ in your own words.
Ans: – There present an ozone layer in the atmosphere which protect our earth from the incoming radiation so, if this layer gets affected by the liberation of various toxic gases like methane, CFC, CO2, SO2 etc. And after this a whole creates which is also the reason behind the temperature increases of earth, this is known greenhouse effect.
9)Prepare a brief speech on global warming. You have to deliver the speech in your class.
Ans: – The global warming is increasing day by day which must be in our control. And for this we should take this necessary step like tree plantation, stops the deforestation, make awareness about the various effect of the increasing the temperature in environment. The increase of temperature in earth is the cause behind the different climatic hazards in different places.
10)Describe the threat to the beauty of the Taj Mahal.
Ans: – The threat behind the beauty of the Taj Mahal is a factory present other part of the Yamuna River. From these factories various gases are liberated which after reaction makes the acids rain and this water when dropped on the marble of the Taj Mahal affect its beauty. Although various steps are taken by the government in this regard.
11)Why does the increased level of nutrients in the water affect the survival of aquatic organisms?
Ans: – The different waste from various sources increases the nutrients in water. Like the chemical waste from the field or the factories, the waste from the house which after mixing with the water the level of nutrients increase as a result the westerly plant increase which also know as eutrophication. Because of this the oxygen levels decrease in the water and the aquatic animal get affected.