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
Answer: Option B
A. Bacterial stability factor
B. Relative stability
C. Biological oxygen demand (BOD)
D. Oxygen ion concentration
Answer: Option B
Fluorosis is caused due to the presence of excessive amount of __________ in drinking water.
A. Mercury
B. Lead
C. Fluoride
D. Arsenic
Smog is not formed due to the presence of __________ in the atmosphere.
A. SO2
B. NOx
C. CO2
D. Any of these
Dose of chlorine for disinfection of water is about __________ mg/litre of water.
A. 0.01
B. 0.1
C. 0.3
D. 1
Join The Discussion