Q1: 1. What is the primary purpose of domestic wastewater treatment?

• A) A. To increase water consumption
• B) B. To remove pollutants and contaminants
• C) C. To accelerate plant growth
• D) D. To promote algae growth

Q2: 2. Which of the following is a common method used in domestic wastewater treatment?

• A) A. Dumping untreated wastewater into rivers
• B) B. Composting wastewater at home
• C) C. Activated sludge process
• D) D. Burning wastewater in open fields

Q3: 3. What is the role of a septic tank in domestic wastewater treatment?

• A) A. Filtering out microplastics
• B) B. Treating wastewater using UV light
• C) C. Settling solids and allowing biological digestion
• D) D. Storing wastewater for future use

Q4: 4. Which of the following is a secondary treatment process in domestic wastewater treatment?

• A) A. Screening
• B) B. Sedimentation
• C) C. Aeration
• D) D. Filtration

Q5: 5. What is the purpose of disinfection in the final stage of domestic wastewater treatment?

• A) A. To add color to the water
• B) B. To remove dissolved oxygen
• C) C. To kill harmful bacteria and pathogens
• D) D. To increase nutrient levels

Q6: 6. Which of the following is a common problem associated with untreated domestic wastewater?

• A) A. Improved soil fertility
• B) B. Groundwater pollution
• C) C. Increased biodiversity
• D) D. Enhanced aquatic life

Q7: 8. Which process involves the breakdown of organic matter by microorganisms in domestic wastewater treatment?

• A) A. Coagulation
• B) B. Flocculation
• C) C. Aerobic digestion
• D) D. Reverse osmosis

Q8: 9. What is the purpose of a clarifier in the treatment of domestic wastewater?

• A) A. To add chemicals for disinfection
• B) B. To remove large particles through settling
• C) C. To increase the pH of the water
• D) D. To speed up the filtration process

Q9: 10. Which technology utilizes plants to naturally treat domestic wastewater?

• A) A. Reverse osmosis
• B) B. Constructed wetlands
• C) C. Ultraviolet disinfection
• D) D. Ion exchange

Q10: 11. How does the activated sludge process work in domestic wastewater treatment?

• A) A. By using physical barriers to filter water
• B) B. By adding chemicals to neutralize pollutants
• C) C. By mixing wastewater with microorganisms in aeration tanks
• D) D. By exposing wastewater to high temperatures

Q11: 12. Which of the following is a benefit of recycling treated domestic wastewater for irrigation?

• A) A. Increased water scarcity
• B) B. Reduced demand on freshwater sources
• C) C. Introduction of harmful chemicals into soils
• D) D. Accelerated erosion of topsoil

Q12: 13. What is the purpose of aeration in the treatment of domestic wastewater?

• A) A. To remove dissolved oxygen
• B) B. To promote anaerobic conditions
• C) C. To provide oxygen for microorganisms to break down organic matter
• D) D. To increase the concentration of solids in the water

Q13: 14. Which method is used to remove suspended solids in the primary treatment of domestic wastewater?

• A) A. Filtration
• B) B. Sedimentation
• C) C. Disinfection
• D) D. Coagulation

Q14: 15. What is the function of a trickling filter in domestic wastewater treatment?

• A) A. To remove dissolved gases
• B) B. To increase the temperature of the water
• C) C. To provide a surface for microorganisms to grow and treat wastewater
• D) D. To accelerate the settling of solids

Q15: 16. Which of the following is a common challenge in domestic wastewater treatment plants?

• A) A. Excessive removal of nutrients
• B) B. Accidental release of treated wastewater into water bodies
• C) C. Low levels of dissolved oxygen
• D) D. Rapid treatment process