Concept of BOD
Trending Questions
Three water samples namely river water, untreated sewage water and secondary effluent discharged from a sewage treatment plant were subjected to the BOD test. The samples were labelled A, B and C; but the laboratory attendant did not note which was which. The BOD values of the three samples A, B and C were recorded as 20 mg/L, 8 mg/L and 400 mg/L, respectively. Which sample of the water is most polluted?
Can you assign the correct label to each assuming the river water is relatively clean?
Clean water would have BOD value of less than ?
- Industrial wastes poured into water bodies
- extent to which water is polluted with organic compound
- amount of carbon monoxide inseperably combined with haemoglobin
- amount of oxygen needed by green plants during night
How is the BOD of waste water related to polluting potential?
Which of the following is/are products of wastewater treatment?
Biogas
Sludge
Both biogas and sludge
Aerator
- Drying of the river very soon due to algal bloom.
- Increased population of aquatic food web organisms.
- An increased production of fish due to biodegradable nutrients.
- Death of fish due to lack of oxygen.
How does the biological oxygen demand get affected with the increased presence of organic matter in water?
the oxygen demand remains unchanged
None of the above
the oxygen demand decreases
the oxygen demand increases
- reduce
- maintain
- increase
- none of the above
- True
- False
What is NOT true about BOD?
It is a result of a biological process
Polluted water has high BOD
River at its source has high BOD
Oxygen is required for the degradation of organic matter
- has no relationship with concentration of oxygen in the water
- gives a measure of the Salmonella in the water
- increases when sewage gets mixed in the water
- remains unchanged in the presence of algal bloom
- COD
- LOD
- BOD
- MOD
How does the biological oxygen demand get affected with the increased presence of organic matter in water?
The oxygen demand increases
The oxygen demand decreases
The oxygen demand remains unchanged
None of the above
- Industrial wastes poured into water bodies.
- Extent to which water is polluted with organic compounds.
- Amount of carbon monoxide inseparably combined with haemoglobin.
- Amount of oxygen needed by green plants during night.
- sugar industry
- domestic sewage
- dairy industry
- petroleum industry
- has no relationship with concentration of oxygen in the water
- increases when sewage gets mixed in the water
- remains unchanged in the presence of algal bloom
- gives a measure of the Salmonella in the water
- Death of fish due to lack of oxygen
- Increased population of aquatic food web organisms
- Drying of the lake very soon due to algal bloom
- An increased production of fish due to lot of nutrients
What is NOT true about BOD?
It is a result of a biological process
Polluted water has high BOD
River at its source has high BOD
Oxygen is required for the degradation of organic matter
- Anaerobic as it released more energy.
- Aerobic as it was more complex.
- Aerobic as it released more energy.
- Anaerobic because early atmosphere contained little or no oxygen.
- True
- False
- Death of fish due to lack of oxygen
- Drying of the lake vary soon due to algal bloom
- An increased growth of fishes due to lot of nutrients
- Increased population of aquatic food web organisms
How does the biological oxygen demand get affected with the increased presence of organic matter in water?
The oxygen demand increases
The oxygen demand decreases
The oxygen demand remains unchanged
None of the above
- Being contaminated with sewage
- Being aerated
- Receiving minerals
- Atrophic
- The amount of O2 utilised by organisms in water.
- The amount of O2 utilized by microorganisms for decomposition.
- The total amount of O2 present in water.
- All of the above.
- COD
- LOD
- BOD
- MOD
- Drying of the river very soon due to algal bloom.
- Increased population of aquatic food web organisms.
- An increased production of fish due to biodegradable nutrients.
- Death of fish due to lack of oxygen.
- does not affect
- increases
- decreases
- nullifies