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प्रश्न
Which of the following conditions shows the polluted environment.
(i) pH of rain water is 5.6.
(ii) amount of carbondioxide in the atmosphere is 0.03%.
(iii) biochemical oxygen demand 10 ppm.
(iv) eutrophication.
उत्तर
(iii) biochemical oxygen demand 10 ppm.
(iv) eutrophication.
Explanation:
Polluted water may contain nutrients for the growth of algae, which covers the water surface and reduces the oxygen concentration in water. This leads to anaerobic condition, accumulation of obnoxious decay and animal death. This is process of eutrophication.
The amount of oxygen required by bacteria to break down the organic matter present in a certain volume of sample of water is called Biochemical Oxygen Demand. Clean water would have BOD value of 5 ppm whereas highly polluted could have BOD value of 17 ppm or more.
Normally rain water has pH of 6 due to H+ ion formed by reaction of rain water with carbon dioxide in the atmosphere. When the pH of the rain water drops below 5.6, it is called acid rain.
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संबंधित प्रश्न
Match the List I with List II and select the correct answer using the code given below the lists.
| List I | List II | ||
| A | Stone leprosy | 1 | CO |
| B | Biological magnification | 2 | Green house gases |
| C | Global warming | 3 | Acid rain |
| D | Combination with haemoglobin | 4 | DDT |
Which one of the following diseases is caused by water pollution?
Which is the natural source of air pollution?
Which one of the following rivers is highly polluted?
Name the anthropogenic sources of water pollution.
The consequences of global warming may be:
(i) increase in average temperature of the earth.
(ii) melting of Himalayan Glaciers.
(iii) increased biochemical oxygen demand.
(iv) eutrophication.
How can you apply green chemistry for the following:
To reduce use of synthetic detergents.
Which of the following is not a cause of air pollution?
Explain the causes and consequences of air pollution.
Read the given source and answer the questions that follow:
|
The main sources of noise pollution are various factories, mechanized construction and demolition Works, automobiles and aircraft, etc. There may be added periodical but polluting noise from sirens, loudspeakers used in various festivals, programmes associated with community activities. The level of steady noise is measured by sound level expressed in terms of decibels (dB). Of all these sources, the biggest nuisance is the noise produced by traffic, because its intensity and nature depend upon factors, such as the type of aircraft, vehicle, train and the condition of road, as well as, that of vehicle (in case of automobiles). In sea traffic, the noise pollution is confined to the harbour due to loading and unloading activities being carried. Industries cause noise pollution but with varying intensity depending upon the type of industry. Noise pollution is location specific and its intensity declines with increase in distance from the source' of pollution, i.e. industrial areas, arteries of transportation, airport, etc. Noise Pollution is hazardous in many metropolitan and big cities in India. |
- Explain the meaning of noise pollution.
- Why is noise pollution hazardous in metropolitan cities in India?
- "Noise pollution is location specific." Explain with argument.
