PMT 108 Principles of water Test
4 Questions With Complete
Solutions
Course
PMT 108
1. Which percentage of Earth's water is freshwater?
A. 30%
B. 10%
C. 2.5%
D. 15%
Answer: C. 2.5%
Solution:
Approximately 97.5% of Earth's water is saline, while only 2.5% is freshwater. Most freshwater is
locked in glaciers and ice caps.
2. Which process converts liquid water into water vapor?
A. Condensation
B. Evaporation
C. Precipitation
D. Infiltration
Answer: B. Evaporation
Solution:
Evaporation occurs when heat energy changes liquid water into water vapor.
3. Which water quality parameter measures acidity or alkalinity?
A. Turbidity
,B. Hardness
C. pH
D. Conductivity
Answer: C. pH
Solution:
The pH scale ranges from 0 to 14, with 7 being neutral, values below 7 acidic, and values above
7 alkaline.
4. Water hardness is primarily caused by dissolved:
A. Sodium and potassium
B. Calcium and magnesium
C. Iron and aluminum
D. Chloride and sulfate
Answer: B. Calcium and magnesium
Solution:
Hard water contains elevated concentrations of calcium (Ca²⁺) and magnesium (Mg²⁺) ions.
5. Which unit is commonly used to measure turbidity?
A. mg/L
B. NTU
C. ppm
D. mS/cm
Answer: B. NTU
Solution:
Turbidity is measured in Nephelometric Turbidity Units (NTU).
6. Which process removes suspended solids by allowing them to settle?
, A. Chlorination
B. Sedimentation
C. Aeration
D. Fluoridation
Answer: B. Sedimentation
Solution:
Sedimentation uses gravity to separate suspended particles from water.
7. Which chemical is most commonly used for drinking water disinfection?
A. Chlorine
B. Nitrogen
C. Oxygen
D. Hydrogen
Answer: A. Chlorine
Solution:
Chlorine effectively destroys many disease-causing microorganisms and provides a residual
disinfectant.
8. What is the primary purpose of coagulation during water treatment?
A. Increase pH
B. Kill bacteria
C. Destabilize suspended particles
D. Increase dissolved oxygen
Answer: C. Destabilize suspended particles
Solution:
Coagulants neutralize particle charges, allowing particles to clump together into flocs.
4 Questions With Complete
Solutions
Course
PMT 108
1. Which percentage of Earth's water is freshwater?
A. 30%
B. 10%
C. 2.5%
D. 15%
Answer: C. 2.5%
Solution:
Approximately 97.5% of Earth's water is saline, while only 2.5% is freshwater. Most freshwater is
locked in glaciers and ice caps.
2. Which process converts liquid water into water vapor?
A. Condensation
B. Evaporation
C. Precipitation
D. Infiltration
Answer: B. Evaporation
Solution:
Evaporation occurs when heat energy changes liquid water into water vapor.
3. Which water quality parameter measures acidity or alkalinity?
A. Turbidity
,B. Hardness
C. pH
D. Conductivity
Answer: C. pH
Solution:
The pH scale ranges from 0 to 14, with 7 being neutral, values below 7 acidic, and values above
7 alkaline.
4. Water hardness is primarily caused by dissolved:
A. Sodium and potassium
B. Calcium and magnesium
C. Iron and aluminum
D. Chloride and sulfate
Answer: B. Calcium and magnesium
Solution:
Hard water contains elevated concentrations of calcium (Ca²⁺) and magnesium (Mg²⁺) ions.
5. Which unit is commonly used to measure turbidity?
A. mg/L
B. NTU
C. ppm
D. mS/cm
Answer: B. NTU
Solution:
Turbidity is measured in Nephelometric Turbidity Units (NTU).
6. Which process removes suspended solids by allowing them to settle?
, A. Chlorination
B. Sedimentation
C. Aeration
D. Fluoridation
Answer: B. Sedimentation
Solution:
Sedimentation uses gravity to separate suspended particles from water.
7. Which chemical is most commonly used for drinking water disinfection?
A. Chlorine
B. Nitrogen
C. Oxygen
D. Hydrogen
Answer: A. Chlorine
Solution:
Chlorine effectively destroys many disease-causing microorganisms and provides a residual
disinfectant.
8. What is the primary purpose of coagulation during water treatment?
A. Increase pH
B. Kill bacteria
C. Destabilize suspended particles
D. Increase dissolved oxygen
Answer: C. Destabilize suspended particles
Solution:
Coagulants neutralize particle charges, allowing particles to clump together into flocs.
