0.002
0.2
1.2
4.8
✅ The correct answer is option B.
Enviornmental Engineering MCQs
Infective bacteria in water is killed by the __________ process.
Sterilisation
Aeration
Disinfection
None of these
✅ The correct answer is option A.
__________ content of the phosphate rock is the pollutant of primary interest in a phos-phatic fertiliser plant.
Calcium
Fluorine
Phosphorous
Sulphur
✅ The correct answer is option B.
Fluorosis is caused due to the presence of excessive amount of __________ in drinking water.
Mercury
Lead
Fluoride
Arsenic
✅ The correct answer is option C.
Which of the following is the most efficient for removal of very finely divided suspended solids and colloidal matter from the polluted water stream?
Sedimentation tank
Circular clarifier
Mechanical flocculation
Chemical coagulation
✅ The correct answer is option D.
Smog is not formed due to the presence of __________ in the atmosphere.
SO₂
NOx
CO₂
Any of these
✅ The correct answer is option C.
Permissible safe limit (TLV) of __________ toxic gas is 100-1000 parts per million (ppm).
Highly
Moderately
Extremely
Very extremely
✅ The correct answer is option B.
Which of the following is the most major constituents of air pollutants?
Oxides of sulphur
Oxides of nitrogen
Carbon monoxide
Hydrogen sulphide
✅ The correct answer is option A.
Which of the following is not a source of ozone emission in the atmosphere?
Refrigerators
Xerox machines
Dermatological photo-therapy equipments
High voltage electrical equipments
✅ The correct answer is option A.