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1. What is the primary purpose of drinking water treatment?
A. To increase water hardness
B. To produce safe, potable water for consumers
C. To increase water pressure
D. To remove all dissolved minerals
Explanation: The primary goal of water treatment is to provide water that is
safe to drink and meets public health standards.
2. Which microorganism is commonly used as an indicator of fecal
contamination?
A. Giardia
B. Cryptosporidium
C. Escherichia coli (E. coli)
D. Algae
,Explanation: E. coli is the standard indicator organism used to detect possible
fecal contamination.
3. The Safe Drinking Water Act is primarily enforced by which federal agency?
A. USDA
B. OSHA
C. CDC
D. Environmental Protection Agency (EPA)
Explanation: The EPA establishes and enforces national drinking water
standards.
4. What is turbidity?
A. Water temperature
B. Water hardness
C. The cloudiness caused by suspended particles
D. Chlorine concentration
Explanation: Turbidity measures how cloudy water is due to suspended solids.
5. Which treatment process primarily removes suspended solids by gravity?
A. Filtration
B. Disinfection
C. Aeration
D. Sedimentation
Explanation: Sedimentation allows heavier particles to settle out before
filtration.
6. Which chemical is most commonly used for coagulation?
, A. Sodium chloride
B. Calcium carbonate
C. Aluminum sulfate (alum)
D. Potassium chloride
Explanation: Alum destabilizes suspended particles, allowing them to form
larger flocs.
7. Flocculation follows which treatment step?
A. Filtration
B. Disinfection
C. Coagulation
D. Fluoridation
Explanation: Flocculation gently mixes coagulated particles into larger flocs.
8. What is the primary purpose of filtration?
A. Increase pH
B. Remove chlorine
C. Remove remaining suspended particles
D. Add oxygen
Explanation: Filtration removes particles remaining after sedimentation.
9. Which disinfectant provides a lasting residual in the distribution system?
A. Ozone
B. UV light
C. Chlorine
D. Boiling