Tag: causes of resource depletion
Questions Related to causes of resource depletion
HCs are thermodynamically not stable towards
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Acidification
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Decomposition
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Reduction
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Oxidation
Which among the following alkane has largely replaced the ozone layer-depleting halomethanes in household refrigerators and freezers?
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Methane
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Propane
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Butane
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Ethane
Ozone depletion is occurring due to
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PCB
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CO
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PAN
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None of the above
Ozone is the protective layer present in the stratosphere. The harmful ultraviolet radiation is absorbed by the ozone layer. They are carried high into the stratosphere by wind action. Depletion begins when CFC’s get into the stratosphere. Ultraviolet radiation from the sun breaks up these CFCs. The breaking up action releases chlorine atoms. Chlorine atoms react with ozone, starting a chemical cycle that destroys the good ozone in that area. It is not depleted by PCB, carbon monoxides, and PAN.
The major pollutants to deplete ozone are
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Chlorofluorocarbons
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Nitrogen oxides
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Hydrocarbons
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All of the above
Pollution leads to the addition of harmful components in the environment which adversely affect the quality of the environment. CFCs is an organic compound and a volatile derivative of methane, ethane, and propane. It is known as Freon. They are used as a refrigerant. The radical chlorine escapes from CFC in the presence of UV radiation and is long lived in the upper atmosphere where it catalyzes the conversion of ozone into oxygen molecule.
Ozone layer of upper atmosphere is being destroyed by
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Sulphurdioxide
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Carbondioxide
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Chlorofluorocarbon
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Smog
Ozone protects biosphere from high energy
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Infra-red rays
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Ultraviolet rays
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X - rays
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Gamma rays
The ozone layer is mainly found in the stratosphere. Ozone layer acts as a shield that absorbs ultraviolet radiation from the sun. UV rays are highly injurious to living organisms since DNA and proteins of living organisms preferentially absorb UV rays, and its high energy breaks the chemical bonds within these molecules. UV-B damages DNA and mutation may occur. It causes aging of the skin, damage to skin cells and various types of skin cancers.
Chlorofluorocarbon releases a chemical harmful to ozone
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Fluorine
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Sulphur dioxide
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Nitrogen peroxide
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Chlorine
Ozone gas is a layer which is present in the stratosphere and absorbs the harmful ultraviolet radiation. The ozone depletion takes due to the excessive emission of (CFCs). CFC find wide use as refrigerants. CFCs discharged in the lower part of atmosphere move upward and reach stratosphere. In stratosphere, UV rays act on them releasing Cl atoms. Cl degrades ozone releasing molecular oxygen, with these atoms acting merely as catalysts; Cl atoms are not consumed in the reaction. Hence, whatever CFCs are added to the stratosphere, they have permanent and continuing affects on ozone levels. This has resulted in formation of a large area of thinned ozone layer, commonly called as the ozone hole.
Ozone layer is disturbed by
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Large number of factories
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Supersonic jets
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Large number of automobiles
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None of these
- Huge combustion of fossil fuel and organic matter.
- Excessive use of nitrogenous fertilizers.
- supersonic rockets and space shutters.
- Nuclear test.
- Excessive use of chlorofluorocarbons.
The common refrigerant chlorofluoromethane (freon) and NO$ _x$ is a serious pollutant because
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It destroys haemoglobin
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It disrupts O$ _3$ layer
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It lowers atmospheric temperature
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It prevents cloud condensation
CFCs used in refrigerators cause
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Water pollution
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Ozone depletion
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Acid rain
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Photochemical smog
The presence of CFCs in the atmosphere results in the depletion of the ozone layer. They are used as coolants in refrigerators, coolers, etc. The CFCs causes the breaking of the ozone molecule which forms the oxygen radical and O$ _2$. The depletion of the ozone layer results in the penetration of the harmful UV radiations from the sun into the Earth's atmosphere.