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Acid rains are produced by
[1988, 89, 91]
NO2 and SO2 after reacting with water in atmosphere produce HNO3 & H2SO4 which fall down as acid rain.
Which one is not a pollutant normally?
CO2 in its normal fraction in air (about 0.03%) is actually not a pollutant but above this it is considered as a pollutant. At the elevated level it becomes a cause for global waring.
Green house effect is warming due to
Increase in the concentration of CO2 do not allow the earth's radiations to go out of earth’s atmosphere and contributes in increasing temperature of earth.
Major aerosol pollutant in jet plane emission is
Fluorides of carbon is the major pollutant from jet plane emission.
Gas released during Bhopal tragedy was
MIC → (Methyl Isocyanate) was the deadly gas leaked from the fertilizer plant of Union Carbide company in Bhopal.
Domestic waste mostly constitutes :
"Domestic waste" means any non-putrescible waste, consisting of combustible materials, such as paper, cardboard, yard clippings, wood, or similar materials, generated in a dwelling, including the real property upon which it is situated, containing four living units or less. These wastes are biodegradable hence, considered as biodegradable pollution.
Most hazardous metal pollutant of automobile exhausts is
Lead (Pb) is the most hazardous metal pollutant present in automobile exhaust.
Ultraviolet radiations from sunlight causes a reaction that produces
Ultraviolet radiation scause photochemical splitting of oxygen molecules in the stratosphere. The nascent oxygen combines with molecular oxygen to form ozone. In troposphere nascent oxygen comes from nitrogen dioxide.
Atmosphere of big/metropolitan cities is polluted most by
Highest DDT deposition shall occur in
DDT is not soluble in water but soluble in fats. Aquatic micro-organisms absorb them in fats where they accumulate to form concentration many times greater than in water. Zooplankton accumulate more concentrations, fishes feeding on zooplanktons also accumulate more concentration and finally birds feeding on fishes contain these compounds in more concentration. This increase in accumulation of toxic substances in the food pyramids is called "Biological magnification."
Which gas contributes most to green house effect?
CO2 is the major green house gas causing green house effect which is released in the atmosphere by burning fossil (combustion) or by activities like animal respiration. Deforestation adds to the increase in CO2 in atmosphere because trees are cut down which are the big absorber of CO2.
Disease caused by eating fish found in water contaminated with industrial waste having mercury is
Drawback of DDT as pesticide is
In 1962, American biologist Rachel Carson published the book Silent Spring, which alleged that DDT caused cancer and harmed bird reproduction by thinning egg shells. This followed the principles of biological magnification, killing higher level organisms like the birds.
DDT is a persistent organic pollutant with a reported half life of between 2-15 years, and is immobile in most soils.
Sound becomes hazardous noise pollution at level
Above 80 dB sound becomes hazardous.
Fish die in water bodies polluted by sewage due to
Sewage kills plant life and also use oxygen for degradation, so oxygen content of water is lowered and hence animal life in water body start decreasing.
The Taj Mahal is threatened due to the effect of
The Taj Mahal is threatened by environmental pollution, especially by acid rain due to sulphur dioxide emitted from Mathura refinery.
When huge amount of sewage is dumped into a river, its B.O.D, will
By dumping of huge amount of sewage, the oxygen levels are depleted, which are reflected in terms of BOD values of water. The number of microbes also increases tremendously and these also consume most of the oxygen. Thus BOD of the river water will increase.
In Minamata Bay Japan, the animals which remained free from Minamata disease, are
Release of mercur y in water causes pollution. Mercury enters the food chain killing fishes. Human beings feeding on such fishes will suffer from minamata disease. Similarly all carnivores feeding on fishes will develop this disease except rabbit because it is herbivore.
Sewage drained into water bodies kill fishes because
Organic pollutants brought in by the sewage drained into water bodies provides nutrients for stimulating growth of algae. Algal bloom reduces availability of light to the submerged plants which get killed. Dead algae and dead submerged plants consume oxygen during decomposition, causing oxygen depletion and increases competition for oxygen.
The worst environmental hazards were created by accidents in nuclear power plant and MIC gas tragedy respectively in
The MIC gas tragedy occurred in Bhopal in 1984 and the Chernobyl tragedy (nuclear power plant) occurred in Ukraine in 1986.
The major contributor of Green House gases to the atmosphere is
The major contributor of Green House gases to the atmosphere is U.S.A., which itself releases around 37% of the chlorofluorocarbons (CFCs).
Phosphate pollution is caused by
Part of fertilizers containing phosphates are passed down into water bodies as surface run off. Sewage contamination also results in algal bloom (eutrophication) due to increased availability of nitrate and phosphate.
The CO2 content in the atmospheric air is about
The content of CO2 in atmospheric air is 0.034%. The main contributors to air are N2 and O2.
In coming years, skin related disorders will be more common due to
Increase in air pollution has resulted in gradual depletion of the ozone layer. This has exposed the earth's surface to the harmful ultraviolet radiations of the sun. Exposure to UV rays increases the risk of skin cancer and other skin related disorders.
Formation of ozone hole is maximum over
Ozone hole is an area with extreme reduction in the ozone concentration. It was discovered over Halley Bay in Antarctica by Farman et. al (1985), members of British Antarctic Survey Team.
Image of the largest Antarctic ozone hole ever recorded in September 2006.