In water treatment plant, zeolite process is used to remove the __________ of water.
For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than __________ ppm.
Fresh sewage is __________ in nature.
In a sedimentation tank, the detention period for water ranges from __________ hours.
On prolonged exposure to high concentration of carbon monoxide (> 5000 ppm), man dies because
Workers working in __________ industry are most prone to white lung cancer.
A standard test for determination of hardness in water is termed as __________ test.
TLV of lead for public sewer/waste water is about __________ ppm.
Presence of nitrates in water in excess of 50 ppm causes
In sewage treatment, the detention period allowed for oxidation ponds ranges from __________ weeks.
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
Fine grit present in sewage is removed in the __________ during sewage treatment.
The lowest layer of atmosphere is known as the
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)
Which of the following is not a weightless pollutant ?
Global warming may result in
Which of the following is the most lethal water pollutant ?
Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyl and haemoglobin breakdown of some animals, beyond TLV (>50 ppm)
The earth's atmosphere is an envelope of gases present upto a height of about __________ kms.
Which of the following is an adsorbant used for the removal of SO2 from gas/air ?
Higher concentration of nitrogen dioxide in atmospheric air causes
The permissible color for domestic water supply is __________ ppm.
High noise levels produced during operation of fans and compressors can be reduced by using
The Killer gas which caused Bhopal gas tragedy in 1984 was