Verified solutions (2026) UPDATE |2026!! STUDY GUIDE EXAM
1. Describe the relationship between bicarbonate and temporary hardness in
water.
Temporary hardness is solely due to the presence of sulfate ions.
Temporary hardness is related to the presence of sodium ions.
Temporary hardness is caused by the absence of bicarbonate.
Temporary hardness is caused by calcium and magnesium ions that
are bonded with bicarbonate.
2. What is the primary purpose of soda ash in water softening?
To increase chlorine levels
To improve water taste
To reduce water hardness
To remove bacteria
3. Describe how insufficient mixing can affect the coagulation process in water
treatment.
Insufficient mixing enhances chemical reactions in water.
Insufficient mixing has no effect on water treatment processes.
Insufficient mixing can lead to ineffective coagulation, resulting in
incomplete removal of impurities.
Insufficient mixing increases the speed of floc formation.
,4. If a water treatment facility needs to lower the pH of its water supply, which
strong acid would be most appropriate to use?
Acetic acid
Hydrochloric acid
Sulfuric acid
Nitric acid
5. If a water treatment facility observes a short circuit during flocculation, what
corrective action should be taken to improve the process?
Change the source of water
Increase mixing intensity
Lower water temperature
Reduce chemical dosage
6. What is the definition of tapered energy mixing in water treatment?
A method of adding chemicals at a constant rate.
A mixing process that gradually reduces energy input to enhance
floc formation.
A technique for increasing water temperature.
A process that involves rapid mixing of water and chemicals.
7. What is the term used to describe the condition where calcium levels exceed
the saturation point in water?
Precipitation
Supersaturation
, Saturation
Dissolution
8. If a water treatment facility is experiencing high levels of magnesium
bicarbonate and needs to convert it to magnesium carbonate, what pH
adjustment should they aim for?
Increase the pH to 9.5
Increase the pH to 8.4
Maintain the pH at 7.0
Decrease the pH to 6.0
9. Describe the role of strong acids in water treatment processes.
Strong acids are used to adjust pH levels and aid in the coagulation
process.
Strong acids are used to neutralize chlorine in water.
Strong acids are primarily used for disinfection purposes.
Strong acids are used to soften water by removing hardness.
10. What is the primary purpose of coagulation and flocculation in water
treatment?
To add chlorine for disinfection.
To remove suspended particles from water.
To increase water temperature.
To soften hard water.
, 11. If a water treatment facility detects chloride levels exceeding the MCL, what
immediate action should be taken?
Increase the chlorine dosage to mask the chloride levels.
Implement corrective measures to reduce chloride levels.
Ignore the results as they are not critical.
Report the findings to the local government without taking action.
12. is an indicator used in titrations for determining water hardness.
EBT
EDTA
MgSO4
CaCO3
13. Describe the significance of tapered energy mixing in the coagulation and
flocculation processes.
Tapered energy mixing is used to cool down water before treatment.
Tapered energy mixing prevents the formation of harmful bacteria.
Tapered energy mixing allows for better floc formation by reducing
turbulence, which helps particles to aggregate.
Tapered energy mixing increases the speed of chemical reactions in
water.
14. If a water treatment facility needs to increase calcium levels to achieve
supersaturation, which method would be most effective?
Adding calcium chloride
Diluting the water with fresh water