A. 10000
B. 5
C. 500
D. 1000
Related Mcqs:
- Dissolved oxygen content in river water is around _____________ ppm?
A. 5
B. 100
C. 250
D. 500 - Presence of ____________ in water stream are deleterious to aquatic life?
A. Soluble and toxic organics
B. Suspended solids
C. Heavy metals and cyanides
D. All A., B. & C. - Replenishment of dissolved oxygen in water stream polluted with industrial waste occurs by________________?
A. Natural aeration of water stream
B. Photosynthetic action of algae
C. Both A. & B.
D. Neither A. nor B. - The detrimental effect on organism and water quality with temperature rise of aquatic system is the reduction of _____________ of water?
A. Dissolved oxygen content
B. Biological oxygen demand
C. Vapor pressure
D. All A., B. and C. - TLV of mercury in potable (drinking) water is about ______________ ppm?
A. 0.001
B. 0.1
C. 1
D. 5 - TLV of lead for public sewer/waste water is about ______________ ppm?
A. 1
B. 25
C. 150
D. 650 - Presence of dissolved impurities of ______________ is responsible for the red brownish color of water?
A. Carbonates
B. Bi-carbonates
C. Iron & manganese
D. Arsenic - The ratio of oxygen available to the oxygen required for stabilisation of sewage is called the __________________?
A. Bacterial stability factor
B. Relative stability
C. Biological oxygen demand (BOD)
D. Oxygen ion concentration - Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at which it acts as a natural asphyxiate is ≥ _____________ percent?
A. 84
B. 88
C. 80
D. 92 - Presence of nitrates in water in excess of 50 ppm causes________________?
A. Methemoglobinemia
B. Gastroenteritis
C. Asphyxiation
D. Tooth decay
