101. Coal mines drainage waste water (acidic in nature) results from the earth's water percolating through the voids created in coal bed during mining. This polluted water which either drains out naturally to water courses or are removed before starting the mining is
102. Fine grit present in sewage is removed in the __________ during sewage treatment.
103. The lowest layer of atmosphere is known as the
104. As per the world health organisation (WHO) specification, the maximum permissible concentration (i.e., TLV) of particulate matter in air is __________ μg/m3.(μg-microgram)
105. Which of the following is not a weightless pollutant ?
106. Global warming may result in
107. Which of the following is the most lethal water pollutant ?
108. Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyl and haemoglobin breakdown of some animals, beyond TLV (>50 ppm)
109. The earth's atmosphere is an envelope of gases present upto a height of about __________ kms.
110. Which of the following is an adsorbant used for the removal of SO2 from gas/air ?
111. Higher concentration of nitrogen dioxide in atmospheric air causes
112. Ozone is
113. The permissible color for domestic water supply is __________ ppm.
114. High noise levels produced during operation of fans and compressors can be reduced by using
115. The Killer gas which caused Bhopal gas tragedy in 1984 was
116. Aerosols present in atmospheric air may be
117. Ethanolamine is an absorbant used for the removal of __________ from air/gas.
118. Which of the following causes death by asphyxiation, if its presence in atmospheric air exceeds maximum allowable concentration (i.e. > 50 ppm) ?
119. __________ plant emits large amount of SO2 as an air pollutant.
120. Noise pollution level in a chemical plant is expressed in
121. The maximum permissible noise level to which a man working in a chemical plant can be exposed for eight hours per day is about __________ decibels.
122. The most commonly used chemical coagulant in water treatment is
123. The biological decomposition of organic substances in wastes controlled conditions is called
124. Lung cancer & DNA breakage are the major ill effects of excessive ozone exposure to human beings. Ozone layer depletion in the atmosphere is mainly caused by the presence of
125. Smog is not formed due to the presence of __________ in the atmosphere.