Which one of the following is a cause of acid rains?
- A.Ozone
- B.Ammonia
- C.Sulphur dioxide
- D.Carbon monoxide
Correct answer
Explanation
The correct answer is C, Sulphur dioxide. Sulphur dioxide dissolves in rainwater to form sulphuric acid, a main cause of acid rain.
Burning coal and oil in power stations, smelters and vehicles releases sulphur dioxide and oxides of nitrogen into the air. These gases react with water vapour and oxygen to form sulphuric acid and nitric acid, which fall as acid rain, snow or fog. Normal rain is slightly acidic, with a pH of about 5.6, because of dissolved carbon dioxide; acid rain has a lower pH. It harms forests, soils, lakes and fish, and corrodes buildings: the yellowing of the Taj Mahal's marble, called marble cancer, has been blamed on it.
A is wrong: ozone in the stratosphere shields us from ultraviolet rays, and it does not form acids in rain. B is wrong: ammonia is a base, so it neutralises acids rather than causing acid rain. D is wrong: carbon monoxide is a poisonous gas that binds to haemoglobin, but it does not dissolve in rain to form an acid.
Exam tip: Acid rain gases are SO2 and NOx; pH below 5.6; Taj Mahal's marble cancer.
Practice Questions
View allThe city of Cartagena, which is famous for Protocol on Biosafety, is located in
- A.Colombia
- B.Venezuela
- C.Brazil
- D.Guyana
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Cartagena is a port city on Colombia's Caribbean coast, where talks on the biosafety protocol were held in 1999. The Cartagena Protocol on Biosafety is a supplementary agreement to the Convention on Biological Diversity of 1992.
Read the full explanation →Which one of the following is NOT a biocontrol agent ?
- A.Bacillus thuringiensis
- B.Ladybird beetle
- C.Trichoderma
- D.Aphid
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An aphid is a sap-sucking insect pest of crops, so it is the target of biocontrol, not an agent of it.
Read the full explanation →Which of the following can be considered associated with mitigation of environmental problems ?
- A.Biomagnification
- B.Accelerated eutrophication
- C.Release of Nuclear wastes
- D.Categorical disposal of different wastes
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Sorting wastes into categories and disposing of each in the proper way reduces pollution, so it helps solve environmental problems rather than cause them.
Read the full explanation →Which one of the following is the nodal agency in India for the United Nations Environment Programme?
- A.The Ministry of Environment, Forest and Climate Change
- B.The Ministry of Science and Technology
- C.The Ministry of Earth Sciences
- D.The Ministry of Home Affairs
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This ministry plans, promotes and coordinates India's environmental policy, so it deals with UNEP on India's behalf. UNEP was set up in 1972 after the United Nations Conference on the Human Environment in Stockholm and has its headquarters in Nairobi, Kenya.
Read the full explanation →Which of the following are the major coral reef areas of India ?
1. Gulf of Kachchh
2. Gulf of Mannar
3. Lakshadweep
4. Andaman and Nicobar Islands
Select the correct answer using the code given below :
- A.1 and 3 only
- B.2 and 4 only
- C.1, 2 and 3 only
- D.1, 2, 3 and 4
Show answer
All four areas are recognised as the major coral reef areas of India. India's coral reefs lie in four main regions.
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