Applied Chemistry Multiple Choice Questions on “Methods of Reducing Water Pollution”.
1. The BOD value of the domestic sewage is about __________
a) 160
b) 161
c) 166
d) 168
Answer: c
Clarification: The BOD value of domestic sewage is about 166ppm. Total quantity of organic matter utilised is called as the BOD.
2. Non hazardous organic wastes from the sewage is to be separated from the ___________
a) Toxic industrial wastes
b) Bacteria
c) Helminth
d) Protozoa
Answer: a
Clarification: Non hazardous organic wastes from the sewage is to be separated from the toxic industrial wastes. The entry of the harmful things into water must be prevented.
3. Domestic water treatment is carried out under __________ conditions.
a) Aerobic
b) Anaerobic
c) Cannot be known
d) Depends on the pollution level of water
Answer: a
Clarification: Domestic water treatment is carried out in presence of the oxygen. The oxygen is taken from the water. So, it is aerobic process.
4. The BOD value of industrial waste must be about _________
a) 100
b) 200
c) 300
d) 400
Answer: b
Clarification: The BOD value of the industrial waste must be about the 200. The BOD value of the paper industry waste is about 370.
5. The BOD value of the food industry is about ___________
a) 742
b) 743
c) 744
d) 745
Answer: d
Clarification: The BOD value of the food industry is about 745. This value is higher than that of the normal limits.
6. In domestic water treatment, after the primary treatment _________ is done.
a) Screening
b) Sedimentation
c) Aerobic process
d) Anaerobic process
Answer: a
Clarification: In domestic water treatment, after the primary treatment of screening is done. Later sedimentation process is done.
7. In the domestic water process, when air is sent during the active sludge, then _________ released.
a) Oxygen
b) Carbondioxide
c) Nitrogen
d) Chlorine
Answer: b
Clarification: When the air is sent during the active sludge, then the carbondioxide is released in domestic water process.
8. In final step of the domestic water process, the effluent contain ___________ BOD.
a) 10ppm
b) 15ppm
c) 20ppm
d) 25ppm
Answer: d
Clarification: The effluent obtained in the final step of the domestic water process contains ammonia ion and having the 25ppm.
9. Aerobic process is also called as ___________
a) Activated sludge process
b) Sludge thickening process
c) Sedimentation
d) Screening
Answer: a
Clarification: Aerobic process is also called as the activated sludge process. The sludge thickening, sedimentation and screening are the steps involved in the domestic water treatment.
10. By aerobic process _________ of biodegradable water is converted into the biomass.
a) 10%
b) 30%
c) 50%
d) 75%
Answer: c
Clarification: By aerobic process the 50% of the biodegradable water is converted into the biomass and the remaining 50% into carbondioxide.
11. In anaerobic treatment the organic acid and alcohol is undergone into ___________ process.
a) Sedimentation
b) Screening
c) Catalysis
d) Fermentation
Answer: d
Clarification: In anaerobic treatment, the organic acid and alcohol is undergone into fermentation at 35oC and the ppm of 5 to 6.