Dissolved oxygen content in river water is around _____________ ppm?
A. 5
B. 100
C. 250
D. 500
Chemical Environmental Engineering
Maximum allowable concentration of CO2 in air for safe working is _____________ ppm (parts per million)?
Maximum allowable concentration of CO2 in air for safe working is _____________ ppm (parts per million)?
A. 50
B. 1000
C. 2000
D. 5000
____________ substances present in sewage are removed in grit chamber during sewage treatment?
____________ substances present in sewage are removed in grit chamber during sewage treatment?
A. Organic
B. Fatty
C. Inorganic
D. Dissolved
Industrial workers working in leather tanning & manufacturing units are prone to suffer from ___________________?
Industrial workers working in leather tanning & manufacturing units are prone to suffer from ___________________?
A. Respiratory ailments (e.g. bronchitis)
B. Skin diseases (e.g. dermatitis)
C. Silicosis
D. Blurred vision
Ionisation potential employed in the industrial electrostatic precipitator is of the order of_______________?
Ionisation potential employed in the industrial electrostatic precipitator is of the order of_______________?
A. 30 to 70 kV DC
B. 30 to 70 kV AC
C. 230 V AC
D. 230 V DC
Noise level during normal conversation among men is about ______________ decibels?
Noise level during normal conversation among men is about ______________ decibels?
A. 10
B. 45
C. 90
D. 115
Exposure to small amount of ______________ results in high blood pressure & heart disease in human beings?
Exposure to small amount of ______________ results in high blood pressure & heart disease in human beings?
A. Hydrogen sulphide
B. Mercury
C. Cadmium
D. Asbestos
Which of the following acts as a natural source of air pollution ?
Which of the following acts as a natural source of air pollution ?
A. Forest fire
B. Deforestation
C. Volcanic eruption
D. None of these
Moist atmospheric air at high temperature (e.g., in summer) having high concentration of sulphur dioxide causes________________?
Moist atmospheric air at high temperature (e.g., in summer) having high concentration of sulphur dioxide causes________________?
A. Fading of dyes on textiles
B. Corrosion, tarnishing & soiling of metals
C. Reduced strength of textiles
D. All A., B. and C.
Tri-sodium phosphate is used in boiler water treatment to reduce____________________?
Tri-sodium phosphate is used in boiler water treatment to reduce____________________?
A. Turbidity
B. Caustic embrittlement
C. Suspended silica
D. Dissolved oxygen