CR-54 Water Conditioning Equipment
Practice Exam Question And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A Instant Download Pdf
1. A sediment filter primarily reduces:
A) Hardness
B) Turbidity
C) pH
D) Chlorine levels
Rationale: Sediment filters trap suspended particles, lowering
turbidity. Stuvia
2. The resin in a water softener exchanges calcium and magnesium
for:
A) Potassium sulfate
B) Sodium ions
C) Chloride ions
D) Hydrogen ions
Rationale: Water softeners typically use sodium ions to replace
hardness ions. Docsity
3. pH in water measures:
A) Hardness
B) Turbidity
C) Acidity or alkalinity
D) Temperature
, Rationale: pH indicates whether water is acidic or alkaline.
Docsity
4. A carbon filter is most effective for removing:
A) Sediment
B) Chlorine and odors
C) Hardness minerals
D) Microbes
Rationale: Activated carbon targets chlorine, taste, and odor
compounds. Docsity
5. Hard water is primarily caused by the presence of:
A) Lead and arsenic
B) Calcium and magnesium
C) Chloride and sulfate
D) Organic matter
Rationale: Hardness results from dissolved calcium and
magnesium salts. Docsity
6. The main component of a reverse osmosis (RO) system is:
A) Brine tank
B) Carbon filter
C) Semi-permeable membrane
D) UV lamp
Rationale: RO uses a membrane to separate dissolved solids
from water. Docsity
7. Which contaminant causes a rotten-egg odor?
A) Hydrogen sulfide
B) Nitrates
C) Chlorine
, D) Iron
Rationale: Hydrogen sulfide gas produces a characteristic sulfur
smell. Docsity
8. A backwash cycle in filtration is used to:
A) Add chemicals to water
B) Clean the media bed
C) Increase pressure
D) Disinfect water
Rationale: Backwash reverses flow to remove trapped debris in
media filters. Docsity
9. A demand-initiated softener regenerates based on:
A) Time of day
B) Actual water usage
C) Manual input
D) Water color
Rationale: It regenerates only when the resin reaches capacity,
saving salt and water. Docsity
10. Alkalinity in water refers to:
A) Hardness
B) Capacity to neutralize acids
C) TDS
D) Conductivity
Rationale: Alkalinity helps buffer pH changes due to
bicarbonates and carbonates. Docsity
11. Total coliform tests are used to detect:
A) Hardness
B) pH imbalance
Practice Exam Question And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A Instant Download Pdf
1. A sediment filter primarily reduces:
A) Hardness
B) Turbidity
C) pH
D) Chlorine levels
Rationale: Sediment filters trap suspended particles, lowering
turbidity. Stuvia
2. The resin in a water softener exchanges calcium and magnesium
for:
A) Potassium sulfate
B) Sodium ions
C) Chloride ions
D) Hydrogen ions
Rationale: Water softeners typically use sodium ions to replace
hardness ions. Docsity
3. pH in water measures:
A) Hardness
B) Turbidity
C) Acidity or alkalinity
D) Temperature
, Rationale: pH indicates whether water is acidic or alkaline.
Docsity
4. A carbon filter is most effective for removing:
A) Sediment
B) Chlorine and odors
C) Hardness minerals
D) Microbes
Rationale: Activated carbon targets chlorine, taste, and odor
compounds. Docsity
5. Hard water is primarily caused by the presence of:
A) Lead and arsenic
B) Calcium and magnesium
C) Chloride and sulfate
D) Organic matter
Rationale: Hardness results from dissolved calcium and
magnesium salts. Docsity
6. The main component of a reverse osmosis (RO) system is:
A) Brine tank
B) Carbon filter
C) Semi-permeable membrane
D) UV lamp
Rationale: RO uses a membrane to separate dissolved solids
from water. Docsity
7. Which contaminant causes a rotten-egg odor?
A) Hydrogen sulfide
B) Nitrates
C) Chlorine
, D) Iron
Rationale: Hydrogen sulfide gas produces a characteristic sulfur
smell. Docsity
8. A backwash cycle in filtration is used to:
A) Add chemicals to water
B) Clean the media bed
C) Increase pressure
D) Disinfect water
Rationale: Backwash reverses flow to remove trapped debris in
media filters. Docsity
9. A demand-initiated softener regenerates based on:
A) Time of day
B) Actual water usage
C) Manual input
D) Water color
Rationale: It regenerates only when the resin reaches capacity,
saving salt and water. Docsity
10. Alkalinity in water refers to:
A) Hardness
B) Capacity to neutralize acids
C) TDS
D) Conductivity
Rationale: Alkalinity helps buffer pH changes due to
bicarbonates and carbonates. Docsity
11. Total coliform tests are used to detect:
A) Hardness
B) pH imbalance
