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Question : 5
Total: 7
In 1987 , the United Nations Environment Programme (UNEP) forged an agreement to freeze the production of a certain chemical to year 1986 level. Name the chemical and the manufacturing companies in which this chemical was being mostly used.
In what way this chemical damages (i) the upper layers of the atmosphere and ultimately (ii) the organisms on the earth.
In what way this chemical damages (i) the upper layers of the atmosphere and ultimately (ii) the organisms on the earth.
Solution:
In 1987 , the United Nations Environment Programme (UNEP) succeeded in forging an agreement to freeze Chlorofluorocarbons (CFC) production at 1986 levels. It is now mandatory for all the manufacturing companies to make CFC-free refrigerators throughout the world. Chlorofluorocarbons or CFCs are the main cause of ozone layer depletion. Chlorofluorocarbons (CFC) are gases used for various purposes including solvents, refrigerants and aerosol sprays.
(i) The molecules of chlorofluorocarbons in the stratosphere are broken down by ultraviolet radiations and release chlorine atoms. These atoms react with ozone and destroy it.
The use of chemicals like CFCs has endangered the ozone layer. Since the ozone layer protects us against the ultraviolet radiation from the Sun, this could damage the environment.
(ii) These ultraviolet radiations are highly damaging to organisms, for example, it is known to cause skin cancer in human beings. Strong ultraviolet rays may lead to minimal growth, flowering and photosynthesis in plants. The forests also have to bear the harmful effects of the ultraviolet rays.
(i) The molecules of chlorofluorocarbons in the stratosphere are broken down by ultraviolet radiations and release chlorine atoms. These atoms react with ozone and destroy it.
The use of chemicals like CFCs has endangered the ozone layer. Since the ozone layer protects us against the ultraviolet radiation from the Sun, this could damage the environment.
(ii) These ultraviolet radiations are highly damaging to organisms, for example, it is known to cause skin cancer in human beings. Strong ultraviolet rays may lead to minimal growth, flowering and photosynthesis in plants. The forests also have to bear the harmful effects of the ultraviolet rays.
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