Sewage Treatment Plant MCQs
Sewage Treatment Plant – MCQs
Class: 7 |
Subject: Science |
Section: 15 – Natural Resources |
Topic: Sewage Treatment Plant
CBSE Board Examination – NCERT Concept Based Objective Questions
1. A Sewage Treatment Plant (STP) is used to:
Answer: B
An STP removes physical, chemical, and biological impurities from sewage before releasing it into the environment.
An STP removes physical, chemical, and biological impurities from sewage before releasing it into the environment.
2. Sewage mainly contains:
Answer: D
Sewage carries organic waste, detergents, oils, and microbes.
Sewage carries organic waste, detergents, oils, and microbes.
3. First step of sewage treatment is:
Answer: B
Bar screens remove large objects like plastics and rags.
Bar screens remove large objects like plastics and rags.
4. Grit removal tank removes:
Answer: A
Heavy particles settle at the bottom.
Heavy particles settle at the bottom.
5. Sedimentation helps in:
Answer: A
Suspended solids settle forming sludge.
Suspended solids settle forming sludge.
6. Aeration tank adds:
Answer: B
Air supports bacterial decomposition of organic waste.
Air supports bacterial decomposition of organic waste.
7. Microorganisms in STP help in:
Answer: B
Bacteria digest organic matter.
Bacteria digest organic matter.
8. Sludge is:
Answer: B
It is separated and further treated.
It is separated and further treated.
9. Treated water is called:
Answer: A
Effluent is released into rivers or reused.
Effluent is released into rivers or reused.
10. Disinfection is done using:
Answer: A
Chlorination kills harmful microbes.
Chlorination kills harmful microbes.
11. Biogas is produced from:
Answer: B
Organic sludge decomposes anaerobically producing methane.
Organic sludge decomposes anaerobically producing methane.
12. STPs help in:
Answer: D
They protect environment and conserve water.
They protect environment and conserve water.
13. Sewer pipes carry:
Answer: B
They transport wastewater to STPs.
They transport wastewater to STPs.
14. Oil & grease are removed in:
Answer: B
Lighter impurities float and are skimmed off.
Lighter impurities float and are skimmed off.
15. Wastewater treatment prevents:
Answer: D
Proper sanitation protects ecosystems.
Proper sanitation protects ecosystems.
16. Clarifier tank is used for:
Answer: A
It allows suspended matter to settle.
It allows suspended matter to settle.
17. Treated water can be reused for:
Answer: D
Reuse conserves freshwater.
Reuse conserves freshwater.
18. Untreated sewage in rivers causes:
Answer: D
It harms aquatic life and humans.
It harms aquatic life and humans.
19. Sanitation refers to:
Answer: D
It ensures public health safety.
It ensures public health safety.
20. Best practice to reduce sewage load:
Answer: B
Responsible use reduces wastewater generation.
Responsible use reduces wastewater generation.