Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYBiodiversity, Conservation and Environmental Issues4 Marks
Question
Gaseous pollutants.
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Answer
$(1)$ Gaseous pollutants are gases which cause air pollution.
$(2)$ Some common gaseous pollutants are $CO_2, CO, SO_2, NO, NO_2,$ etc.
$(3)$ Carbon dioxide $(CO_2)$ : It is a greenhouse gas which is continuously produced due to human activities such as burning of fossil fuels and rampant deforestation. Photosynthesis carried out by plants can balance $CO_2 : O_2$ ratio in the air, provided there is good green cover. $CO_2$_ is also removed from the air by weathering of silicate rocks forming limestone. Aeroplane traffic especially release lot of $CO_2. CO_2$ is the main cause for global warming and climate change.
$(4)$ Carbon monoxide $(CO)$ : $CO$ is a toxic gas produced by incomplete combustion of different fuels. Therefore, vehicular exhausts are the largest source of $CO.$
$(5)$ Nitrogen dioxide $(NO_2)$ and nitrogen monoxide $(NO)$ : Nitrogen oxides are released through automobiles and chemical industries as waste gases. $NOa$ can form nitric acid after reacting with water vapour, this causes irritation to eyes and lungs. Injury to lungs, liver and kidneys is caused due to these gases.
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