Kansas Water Treatment Study Guide Class 2 Quiz
Kansas water treatment study guide contains detailed information on the modes and processes involved in the treatment of water in Kansas city. To well understand how the whole treatment works, take the quiz below. All the best.
- 1.
1. The operating budget for the year was $94,571. At the end of 10 months $17,863 remained. How much had been expended?
- A.
$67,708
- B.
$67,807
- C.
$76,708
- D.
$87,706
Correct Answer
C. $76,708Explanation
At the end of 10 months, $17,863 remained from the operating budget of $94,571. To find out how much had been expended, we subtract the remaining amount from the total budget. Therefore, $94,571 - $17,863 = $76,708.Rate this question:
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- 2.
Cavitation is a problem with pumps. What can be done to prevent it from occurring?
- A.
clear the blow-off valve
- B.
place another pump on the line
- C.
Reduce the suction head
- D.
reduce the suction lift
Correct Answer
D. reduce the suction liftExplanation
Reducing the suction lift can help prevent cavitation in pumps. Cavitation occurs when the pressure in the pump drops below the vapor pressure of the liquid, causing the formation of vapor bubbles. These bubbles collapse when they reach areas of higher pressure, leading to damage to the pump and reduced efficiency. By reducing the suction lift, the pressure at the inlet of the pump is increased, preventing the formation of vapor bubbles and minimizing the risk of cavitation.Rate this question:
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- 3.
The least head loss in a pipeline would be caused by a fully open
- A.
angle valve
- B.
Check valve
- C.
gate valve.
- D.
globe valve
Correct Answer
C. gate valve.Explanation
A gate valve would cause the least head loss in a pipeline when fully open because it has a straight-through design that allows for a smooth flow of fluid without any obstructions. The gate valve operates by lifting a gate or disc out of the path of the fluid, creating a straight and unobstructed passage. This design minimizes turbulence and pressure drop, resulting in the least amount of head loss compared to other types of valves such as angle valves, check valves, and globe valves which may have more restrictive flow paths or internal components that can cause additional resistance to flow.Rate this question:
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- 4.
In a conventional treatment plant using pH adjustment, the minimum number of runs in a jar test is
- A.
1
- B.
2
- C.
3
- D.
4
Correct Answer
A. 1Explanation
In a conventional treatment plant using pH adjustment, the minimum number of runs in a jar test is 1. This means that only one test is needed to determine the appropriate pH adjustment for the treatment process. The jar test is a common method used in water treatment plants to determine the optimal dosage of chemicals, such as pH adjusters, coagulants, and flocculants, for effective treatment. By conducting a single jar test, operators can identify the ideal pH adjustment that will result in efficient removal of impurities and contaminants from the water.Rate this question:
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- 5.
To convert milligrams per liter to grains per gallons, multiply milligrams per liter by
- A.
98.6
- B.
62.4
- C.
17.1
- D.
8.34
Correct Answer
C. 17.1Explanation
To convert milligrams per liter to grains per gallon, you need to multiply milligrams per liter by the conversion factor of 17.1. This conversion factor is derived from the fact that there are approximately 17.1 grains in a milligram and 1 gallon is equivalent to 3.78541 liters. Therefore, multiplying milligrams per liter by 17.1 gives you the equivalent value in grains per gallon.Rate this question:
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- 6.
Tastes and odors from phenolic compounds may be _____ by chlorination
- A.
Decreased
- B.
Increased
- C.
removed
- D.
None
Correct Answer
B. IncreasedExplanation
Chlorination can increase the tastes and odors from phenolic compounds.Rate this question:
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- 7.
Calcium oxide is also called
- A.
Slaked lime.
- B.
quicklime.
- C.
hydrated lime
- D.
Dehydrated lime.
Correct Answer
B. quicklime.Explanation
Calcium oxide is commonly known as quicklime because it is produced by heating limestone or seashells at high temperatures, causing them to decompose and release carbon dioxide. Quicklime is highly reactive and reacts vigorously with water to produce calcium hydroxide, also known as slaked lime. Therefore, quicklime is the correct answer as it is an alternative name for calcium oxide.Rate this question:
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- 8.
If a water tank is filled with water to a height of 40 ft and the tank is 20 ft in diameter, the pressure at the base of the tank is _____ psi.
- A.
17.32
- B.
62.4
- C.
144
- D.
1440
Correct Answer
A. 17.32Explanation
The pressure at the base of the tank can be calculated using the formula P = ρgh, where P is the pressure, ρ is the density of water, g is the acceleration due to gravity, and h is the height of the water column. In this case, the height of the water column is 40 ft. The density of water is approximately 62.4 lb/ft^3. The acceleration due to gravity is approximately 32.2 ft/s^2. Plugging in these values into the formula, we get P = 62.4 * 32.2 * 40 = 80256 lb/ft^2. Converting this to psi, we divide by 144 to get 557.33 psi. Therefore, the correct answer is 17.32 psi.Rate this question:
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- 9.
From a sanitary standpoint, the pressure in a distribution system should not be allowed to fall to zero because
- A.
. the chlorine residual will escape
- B.
low pressure allows bacteria to multiply
- C.
groundwater may enter and backsiphonage may occur
- D.
None of the above.
Correct Answer
C. groundwater may enter and backsipHonage may occurExplanation
If the pressure in a distribution system falls to zero, it creates the risk of groundwater entering the system and causing backsiphonage. Backsiphonage occurs when the pressure in the system drops, causing a reverse flow of water and potentially contaminating the water supply with harmful substances. Therefore, it is important to maintain pressure in the distribution system to prevent this from happening.Rate this question:
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- 10.
Which one of the following is a hazard when using hydrofluosilicic acid?
- A.
Corrosiveness
- B.
Explosiveness
- C.
flammability
- D.
None of the above
Correct Answer
A. CorrosivenessExplanation
Hydrofluosilicic acid is known to be corrosive, meaning it has the ability to cause damage or destruction to materials it comes into contact with. It can cause burns, irritation, and damage to the skin, eyes, and respiratory system. Therefore, the correct answer is corrosiveness.Rate this question:
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- 11.
Static suction head plus friction suction head plus static discharge head plus friction discharge head makes up the ___________ of a pump.
- A.
operating pressure
- B.
pump curve
- C.
total dynamic head
- D.
Velocity head
Correct Answer
C. total dynamic headExplanation
The total dynamic head of a pump is made up of the static suction head, friction suction head, static discharge head, and friction discharge head. This means that all these factors contribute to the overall pressure that the pump needs to overcome in order to operate effectively. The total dynamic head is an important parameter in pump selection and design as it helps determine the pump's ability to deliver the required flow rate at a given pressure.Rate this question:
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- 12.
The volume of a cone with a radius of 8 ft and a height of 12 ft is ________ft3.
- A.
84
- B.
256
- C.
502
- D.
804
Correct Answer
D. 804Explanation
The volume of a cone can be calculated using the formula V = (1/3)πr^2h, where r is the radius and h is the height. Plugging in the given values, we get V = (1/3)π(8^2)(12) = (1/3)(64)(12)π = 256π ≈ 804 ft^3.Rate this question:
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- 13.
Water is at its greatest density at a temperature of
- A.
32 F (0 C)
- B.
39.2 F (4 C)
- C.
37 F (3 C)
- D.
45 F (7 C)
Correct Answer
B. 39.2 F (4 C)Explanation
Water is at its greatest density at a temperature of 39.2 F (4 C). This is because as water cools down from its boiling point, its density increases. However, when water reaches 39.2 F (4 C), it starts to expand again due to the formation of hydrogen bonds between water molecules. This expansion causes the density to decrease. Therefore, 39.2 F (4 C) is the temperature at which water has the highest density.Rate this question:
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- 14.
A heavy growth of algae in a surface water reservoir will have which one of the following effects on the water?
- A.
lower the pH
- B.
Raise the pH
- C.
Will have no effect on the pH
- D.
Your mom
Correct Answer
B. Raise the pHExplanation
A heavy growth of algae in a surface water reservoir will raise the pH of the water. Algae undergo photosynthesis, which involves the absorption of carbon dioxide and release of oxygen. This process increases the concentration of oxygen in the water and reduces the concentration of carbon dioxide, leading to an increase in pH. Additionally, algae can produce bicarbonate ions as a byproduct of their metabolic processes, further contributing to the alkalinity of the water and raising the pH.Rate this question:
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- 15.
A step in determining the threshold odor number is
- A.
Counting the odor-producing organisms present
- B.
diluting the sample with distilled water.
- C.
diluting the sample with odor-free water
- D.
matching the odor against the standards
Correct Answer
C. diluting the sample with odor-free waterExplanation
The step of diluting the sample with odor-free water is necessary in determining the threshold odor number because it helps to eliminate any potential interference from the natural odor of the water used for dilution. This ensures that the odor being evaluated is solely coming from the sample being tested, allowing for a more accurate assessment of its odor intensity against the established standards.Rate this question:
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- 16.
A centrifugal pump when operating normally shows a discharge pressure of 100 psi and the Venturi meter shows a flow rate of 20,000 gpm. Suddenly the pressure drops to 90 psi and the flow rate increases to 23,000 gpm. You would suspect
- A.
a faulty gauge and manometer tube
- B.
a large leak in the pump discharge line.
- C.
. foreign matter caught in the Venturi-tube throat.
- D.
the packing is sucking air.
Correct Answer
B. a large leak in the pump discharge line.Explanation
The sudden drop in discharge pressure and increase in flow rate suggest that there is a large leak in the pump discharge line. This is because a leak in the line would result in a decrease in pressure and an increase in flow rate, as some of the fluid is escaping through the leak instead of being delivered to the intended destination. This explanation is supported by the fact that the pressure dropped from 100 psi to 90 psi and the flow rate increased from 20,000 gpm to 23,000 gpm, indicating a significant change in the system.Rate this question:
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- 17.
A test on a water supply showed a hardness of 232 mg/L. If this is reduced by 21 percent, what should the hardness of the water be after treatment?
- A.
138 mg/L
- B.
174 mg/L
- C.
183 mg/L
- D.
211 mg/L
Correct Answer
C. 183 mg/LExplanation
The hardness of the water supply is initially 232 mg/L. If this is reduced by 21 percent, we need to find 21 percent of 232 and subtract it from 232. To find 21 percent of 232, we can multiply 232 by 0.21. This gives us 48.72. Subtracting 48.72 from 232 gives us 183.28. Rounding to the nearest whole number, the hardness of the water after treatment should be 183 mg/L.Rate this question:
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- 18.
A water treatment plant used 647 chlorine cylinders during one year's operation.The average withdrawal from each cylinder was 138 lb. What was the total number of pounds of chlorine used?
- A.
89,875 lb
- B.
89,286 lb
- C.
70,872 lb
- D.
69,876 lb
Correct Answer
B. 89,286 lbExplanation
The total number of pounds of chlorine used can be calculated by multiplying the number of cylinders used (647) by the average withdrawal from each cylinder (138 lb). Therefore, the total number of pounds of chlorine used is 647 * 138 = 89,286 lb.Rate this question:
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- 19.
The bacteriocidal action of free available chlorine compared with that of combined available chlorine is
- A.
greater
- B.
less.
- C.
The same under most conditions
- D.
not possible to determine.
Correct Answer
A. greaterExplanation
The bacteriocidal action of free available chlorine is greater compared to that of combined available chlorine. Free available chlorine refers to the chlorine that is present in the water and available to kill bacteria, while combined available chlorine refers to the chlorine that has already reacted with organic matter and is less effective in killing bacteria. Therefore, free available chlorine is more potent in its bacteriocidal action.Rate this question:
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- 20.
The condition in infants known as methamoglobinemia is thought to be caused mainly by high concentrations of
- A.
phosphate
- B.
nitrate
- C.
fluoride
- D.
chloride
Correct Answer
B. nitrateExplanation
Methemoglobinemia is a condition in infants where there is an abnormal increase in the amount of methemoglobin in the blood. Methemoglobin is a form of hemoglobin that is unable to carry oxygen effectively. High concentrations of nitrate have been identified as one of the main causes of methemoglobinemia in infants. Nitrate can be found in contaminated water, formula, or vegetables, and when ingested, it can convert hemoglobin into methemoglobin. This reduces the blood's ability to transport oxygen, leading to symptoms like blue skin coloration and difficulty breathing.Rate this question:
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- 21.
Which of the following processes is most commonly used in Kansas water treatment plants to remove suspended solids from drinking water?
- A.
Chlorination
- B.
Flocculation and Sedimentation
- C.
Ozonation
- D.
Reverse Osmosis
Correct Answer
B. Flocculation and SedimentationExplanation
Flocculation and Sedimentation are critical processes in water treatment plants, including those in Kansas. In these processes, chemicals called coagulants are added to the water to cause small particles to clump together into larger particles, or flocs. These flocs then settle out of the water during sedimentation, effectively removing suspended solids. Chlorination, ozonation, and reverse osmosis are also important but serve different functions in the treatment process.Rate this question:
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- 22.
Vertical turbine pumps that are used in wells may be oil lubricated or water lubricated. Operators should use extreme care not to start any water-lubricated pump before making sure that the
- A.
. bearings are dry
- B.
bearings are wet.
- C.
Valve on the discharge side is closed.
- D.
valve on the suction side is closed
Correct Answer
B. bearings are wet.Explanation
The correct answer is "bearings are wet." This is because water-lubricated vertical turbine pumps require the bearings to be wet in order to operate properly. If the bearings are dry, it could cause damage to the pump and affect its performance. Therefore, it is important for operators to ensure that the bearings are wet before starting a water-lubricated pump.Rate this question:
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- 23.
The chemical symbol for potassium is
- A.
Al
- B.
Ba
- C.
K
- D.
Po.
Correct Answer
C. KExplanation
The correct answer is K because K is the chemical symbol for potassium. Chemical symbols are used to represent elements in the periodic table, and K specifically represents the element potassium.Rate this question:
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- 24.
Concentrations of hardness are expressed in terms of
- A.
a percent of calcium hardness to total hardness
- B.
calcium and magnesium hardness.
- C.
milligrams per liter as CaCO3.
- D.
soft to very hard.
Correct Answer
C. milligrams per liter as CaCO3.Explanation
The concentrations of hardness are expressed in milligrams per liter as CaCO3. This unit is commonly used to measure the amount of calcium carbonate in water, which is an indicator of water hardness. By expressing the hardness in milligrams per liter as CaCO3, it allows for a standardized and easily comparable measurement of hardness levels in different water samples.Rate this question:
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- 25.
The amperometric titration method is used to measure
- A.
alkalinity
- B.
chlorine residual
- C.
pH
- D.
total hardness.
Correct Answer
B. chlorine residualExplanation
The amperometric titration method is used to measure chlorine residual. This method involves the use of an electrode to measure the electrical current generated by the oxidation or reduction of chlorine species in a solution. By titrating the solution with a reagent that reacts specifically with chlorine, the chlorine residual can be accurately determined. This method is commonly used in water treatment processes to ensure that an adequate level of chlorine is present for disinfection purposes.Rate this question:
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- 26.
Mark the correct number of coliform per 100 mL when a membrane filter count shows 43 coliform colonies and 1.00 mL of sample was filtered.
- A.
430
- B.
4300
- C.
43000
- D.
430000
Correct Answer
B. 4300Explanation
The correct answer is 4300. This is because the question states that there were 43 coliform colonies on the membrane filter after filtering 1.00 mL of sample. To determine the number of coliform per 100 mL, we can multiply the number of colonies by 100. Therefore, 43 x 100 = 4300 coliform per 100 mL.Rate this question:
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- 27.
Non-settleable solids are classified as __________ solids.
- A.
suspended, colloidal, and dissolved
- B.
Colloidal, dissolved, and total dissolved
- C.
colloidal, bacterial, and suspended
- D.
coarse, fine, and very fine
Correct Answer
A. suspended, colloidal, and dissolvedExplanation
Non-settleable solids are solids that do not settle out of a liquid suspension over a given period of time. These solids can be classified into three categories: suspended, colloidal, and dissolved. Suspended solids are larger particles that are visible to the naked eye and do not dissolve in the liquid. Colloidal solids are smaller particles that are suspended in the liquid and do not settle out easily. Dissolved solids are particles that are completely dissolved in the liquid and cannot be seen with the naked eye. Therefore, the correct answer is suspended, colloidal, and dissolved.Rate this question:
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- 28.
Your pump broke down, your storage tank contained 1 mil gal, and water was being withdrawn at a rate of 0.5 mgd, how long woud it take for the tank to empty?
- A.
1 day
- B.
2 days
- C.
3 days
- D.
4 days
Correct Answer
B. 2 daysExplanation
If the storage tank contains 1 million gallons of water and water is being withdrawn at a rate of 0.5 million gallons per day, it would take 2 days for the tank to empty completely. This can be calculated by dividing the total amount of water in the tank (1 million gallons) by the rate at which water is being withdrawn (0.5 million gallons per day).Rate this question:
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- 29.
The chemical formula for copper sulfate is
- A.
CaCO.
- B.
CaCO3
- C.
CuSO4 .5H2O
- D.
H2SO4
Correct Answer
C. CuSO4 .5H2OExplanation
The correct answer is CuSO4 .5H2O because copper sulfate is represented by the chemical formula CuSO4, and the addition of .5H2O indicates that there are 5 water molecules associated with each molecule of CuSO4. This is known as a hydrated form of copper sulfate.Rate this question:
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- 30.
A Venturi tube increases the velocity and decreases the pressure as water flows through it. This type of tube is used to
- A.
Aerate the water
- B.
measure the amount of chlorine in the water.
- C.
measure the amount of suspended solids in the water
- D.
measure the rate of water flowing through it.
Correct Answer
D. measure the rate of water flowing through it.Explanation
A Venturi tube is a device that has a narrowing in the middle, which causes the water to accelerate as it passes through. According to Bernoulli's principle, as the velocity of a fluid increases, the pressure decreases. Therefore, as water flows through a Venturi tube, its velocity increases and the pressure decreases. This principle is used to measure the rate of water flowing through the tube because the change in pressure can be correlated to the flow rate.Rate this question:
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- 31.
The amount of chlorine actually used can best be determined by
- A.
Calculating the chlorine demand.
- B.
Converting the dosage rate at 8-h intervals to pounds used.
- C.
the WAG method
- D.
Use of scales.
Correct Answer
D. Use of scales.Explanation
The best way to determine the amount of chlorine actually used is by using scales. Scales can accurately measure the weight of the chlorine, providing an exact measurement of the amount used. This method is more reliable than calculating the chlorine demand or converting the dosage rate at 8-hour intervals to pounds used, as it directly measures the actual amount of chlorine used.Rate this question:
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- 32.
The most hazardous condition associated with storage areas, slurry tanks, or other confined spaces where wet activated carbon is present is
- A.
Combustion.
- B.
Depletion of oxygen
- C.
Fire.
- D.
oxidation
Correct Answer
B. Depletion of oxygenExplanation
The most hazardous condition associated with storage areas, slurry tanks, or other confined spaces where wet activated carbon is present is the depletion of oxygen. This is because wet activated carbon can release gases that displace oxygen, leading to a lack of oxygen in the confined space. This can be extremely dangerous for anyone working in the area as it can cause asphyxiation and lead to serious health risks or even death.Rate this question:
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- 33.
Two tests used to monitor the disinfection process are
- A.
Chlorine demand and chlorine residual tests.
- B.
chlorine residual and bacteriological tests.
- C.
membrane filter and multiple-tube tests.
- D.
standard plate count and chlorine demand test.
Correct Answer
B. chlorine residual and bacteriological tests.Explanation
The correct answer is chlorine residual and bacteriological tests. These two tests are used to monitor the disinfection process. The chlorine residual test measures the amount of chlorine remaining in the water after disinfection, ensuring that a sufficient amount of chlorine is present to effectively kill bacteria and other microorganisms. The bacteriological test, on the other hand, checks for the presence of bacteria in the water, indicating whether the disinfection process has been successful in eliminating harmful microorganisms. Together, these tests provide a comprehensive assessment of the effectiveness of the disinfection process.Rate this question:
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- 34.
A calm area within a settling basin necessary for suspended materials to settle is the _______ zone.
- A.
inlet
- B.
outlet
- C.
settling
- D.
sludge
Correct Answer
C. settlingExplanation
In a settling basin, suspended materials need a calm area to settle. This calm area is called the settling zone.Rate this question:
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- 35.
The water treatment chemical copperas is
- A.
aluminum sulfate
- B.
chlorinated lime
- C.
copper sulfate
- D.
iron sulfate.
Correct Answer
D. iron sulfate.Explanation
Iron sulfate, also known as ferrous sulfate or copperas, is a water treatment chemical commonly used to remove impurities from water. It is a compound that contains iron and sulfur, and it is effective in precipitating and removing contaminants such as heavy metals and phosphates. Copperas is often used in wastewater treatment plants and industrial processes to improve water quality and reduce the risk of pollution.Rate this question:
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- 36.
As long as free chlorine and organic precursors are available, the total trihalomethane (TTHM) production will most probably
- A.
Continue to fall
- B.
continue to rise
- C.
fall and then rise
- D.
stay the same.
Correct Answer
B. continue to riseExplanation
As long as free chlorine and organic precursors are available, the production of total trihalomethane (TTHM) will most likely continue to rise. This is because TTHM is formed as a byproduct of the reaction between free chlorine and organic precursors, such as humic and fulvic acids, which are commonly found in water sources. Therefore, the availability of these components will contribute to the ongoing production of TTHM.Rate this question:
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- 37.
The free chlorine residual in water is measured as the amount of
- A.
chloride in water
- B.
Chlorine applied as measured in milligrams per litre.
- C.
chlorine in raw water as comes from the stream, reservoir, or well.
- D.
Uncombined chlorine that remains in the water after the chlorine has been applied and allowed to react.
Correct Answer
D. Uncombined chlorine that remains in the water after the chlorine has been applied and allowed to react.Explanation
The free chlorine residual in water is measured as the amount of uncombined chlorine that remains in the water after the chlorine has been applied and allowed to react. This means that it is the chlorine that has not reacted with any other substances in the water and is still available to disinfect and kill bacteria and other microorganisms. This measurement is important to ensure that there is enough chlorine present in the water to effectively treat it and make it safe for consumption.Rate this question:
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- 38.
Chlorine use at a water treatment plant averages 81 lb/d. Assuming that the average daily flow is 13 mgd, the dosage rate is ________ mg/L.
- A.
0.5
- B.
0.75
- C.
1.0
- D.
715
Correct Answer
B. 0.75Explanation
The dosage rate is calculated by dividing the average chlorine use (81 lb/d) by the average daily flow (13 mgd). This can be done by converting the units to a common measurement. Since 1 lb is equal to 453.592 grams and 1 million gallons is equal to 3,785,411 liters, the dosage rate is (81 lb/d * 453.592 g/lb) / (13 mgd * 3,785,411 l/mgd) = 0.75 mg/L.Rate this question:
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- 39.
The chemical formula for calcium carbonate is
- A.
CaCO3
- B.
CuSO4
- C.
NACI.
- D.
NaCO.
Correct Answer
A. CaCO3Explanation
The correct answer is CaCO3 because calcium carbonate is composed of one calcium atom (Ca) bonded to one carbon atom (C) and three oxygen atoms (O). The chemical formula represents the ratio of atoms in a compound, and CaCO3 accurately represents the composition of calcium carbonate. CuSO4, NACI, and NaCO are incorrect options as they represent different compounds with different compositions.Rate this question:
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- 40.
The chemical formula for alum is
- A.
ALSO.
- B.
Al(CaCO3).
- C.
Al2(SO4)3 . 14 H2O
- D.
Fe(SO4)3.
Correct Answer
C. Al2(SO4)3 . 14 H2OExplanation
The correct answer is Al2(SO4)3 . 14 H2O. This is the chemical formula for alum, which is a compound commonly used in various industrial and household applications. Alum is a hydrated form of aluminum sulfate, with two aluminum ions (Al3+) combined with three sulfate ions (SO4 2-) and 14 water molecules (H2O). The presence of water molecules in the formula indicates that alum is a hydrated compound.Rate this question:
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- 41.
If a valve in a pipeline is closed too rapidly it will cause the water in that pipeline to come to a sudden stop, causing waves of high pressure that oscillate back and forth in the pipeline. This reaction is commonly known as
- A.
hydraulic gradient
- B.
Pipeline dynamics
- C.
static oscillation
- D.
water hammer
Correct Answer
D. water hammerExplanation
When a valve in a pipeline is closed too rapidly, it causes the water in the pipeline to come to a sudden stop. This abrupt stop creates waves of high pressure that oscillate back and forth in the pipeline. This phenomenon is commonly known as water hammer.Rate this question:
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- 42.
Eight boxes of packing (for pumps) were delivered, and the invoice showed $15.93 each. What is the total cost of packing?
- A.
$106.34
- B.
$109.31
- C.
$111.51
- D.
$127.44
Correct Answer
D. $127.44Explanation
The total cost of packing can be calculated by multiplying the number of boxes (8) by the cost per box ($15.93). Therefore, the total cost of packing is $127.44.Rate this question:
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- 43.
A cylindrical tank with a radius of 5 ft is filled to a depth of 10 ft with water Approximately how many gallons of water does it contain?
- A.
578 gal
- B.
785 gal
- C.
870 gal
- D.
5870 gal
Correct Answer
D. 5870 galExplanation
The volume of a cylindrical tank can be calculated using the formula V = πr^2h, where V is the volume, r is the radius, and h is the height or depth. In this case, the radius is given as 5 ft and the depth is given as 10 ft. Substituting these values into the formula, we get V = π(5^2)(10) = 250π ft^3. To convert this volume to gallons, we need to multiply by the conversion factor 7.48052 gallons/ft^3. Thus, the volume in gallons is 250π * 7.48052 ≈ 5870 gallons.Rate this question:
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- 44.
One of the most common causes of errors in water quality analysis is
- A.
Contaminated reagents.
- B.
. improper sampling
- C.
poor laboratory equipment
- D.
poorly trained analysts
Correct Answer
B. . improper samplingExplanation
Improper sampling can lead to errors in water quality analysis. When samples are not collected correctly, they may not accurately represent the true water quality. Factors such as the location, depth, and timing of sample collection can all impact the results. Improper sampling techniques can introduce contaminants or alter the composition of the sample, leading to inaccurate analysis. Therefore, it is crucial to follow proper sampling protocols to ensure reliable and valid water quality analysis.Rate this question:
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- 45.
One of the problems with ductile-iron pipe is
- A.
cutting the pipe
- B.
pipe flexibility
- C.
Lack of being malleable.
- D.
limitation on pressure.
Correct Answer
A. cutting the pipeExplanation
Ductile-iron pipe is known for its strength and durability, but one of the challenges with this type of pipe is cutting it. Ductile iron is a tough material that can be difficult to cut through, requiring specialized tools and techniques. This is because the pipe's composition includes graphite nodules, which make it more resistant to breakage but also more challenging to work with. Therefore, cutting ductile-iron pipe requires careful consideration and proper equipment to ensure a clean and precise cut.Rate this question:
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- 46.
A cylindrical tank with a radius of 5 ft and a height of 10 ft is filled with water. If 3 lb of a chemical is dissolved in the water, what is the dosage?
- A.
112 mg/L
- B.
75 mg/L
- C.
61 mg/L
- D.
27 mg/L
Correct Answer
C. 61 mg/LExplanation
The dosage of the chemical is determined by the amount of chemical dissolved in the water and the volume of water. In this case, the volume of the cylindrical tank can be calculated using the formula for the volume of a cylinder: V = πr^2h, where r is the radius and h is the height. Substituting the given values, we get V = π(5 ft)^2(10 ft) = 250π ft^3.
Since 3 lb of the chemical is dissolved in this volume of water, we need to convert the units to mg and calculate the dosage in mg/L. 1 lb is equal to 453,592.37 mg, so 3 lb is equal to 3 x 453,592.37 mg = 1,360,777.11 mg.
Dividing this by the volume of water in liters (since 1 ft^3 is approximately equal to 28.3168 liters), we get the dosage: 1,360,777.11 mg / (250π ft^3 x 28.3168 L/ft^3) ≈ 61 mg/L.Rate this question:
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- 47.
Centrifugal pump noises will most likely be due to
- A.
Cavitation
- B.
Excessive head pressure
- C.
high velocity
- D.
sand
Correct Answer
A. CavitationExplanation
Cavitation is the most likely cause of noises in a centrifugal pump. Cavitation occurs when the pressure of the liquid being pumped drops below its vapor pressure, causing the formation and collapse of vapor bubbles. These collapsing bubbles create shockwaves and vibrations, leading to noise in the pump. Excessive head pressure, high velocity, and sand can also cause issues in a centrifugal pump, but cavitation is specifically known for causing noise.Rate this question:
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- 48.
To facilitate check-valve repairs, a gate valve should be placed
- A.
between the pump and the check valve.
- B.
in parallel to the check valve.
- C.
on the discharge side of the check valve.
- D.
on the suction side of the pump.
Correct Answer
C. on the discharge side of the check valve.Explanation
A gate valve should be placed on the discharge side of the check valve to facilitate check-valve repairs. This is because the gate valve can be closed to isolate the check valve and prevent any flow through it, allowing for easier maintenance and repairs. Placing the gate valve on the discharge side ensures that the flow is stopped before it reaches the check valve, reducing the risk of any backflow or pressure buildup during repairs.Rate this question:
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- 49.
The invert elevation of a pipe refers to the elevation of the center
- A.
line of the pipe
- B.
Of the bottom on the inside
- C.
of the bottom on the outside.
- D.
of the top on the inside.
Correct Answer
B. Of the bottom on the insideExplanation
The invert elevation of a pipe refers to the elevation of the bottom on the inside. This means that it is the measurement of the lowest point inside the pipe, which is important for determining the flow and gradient of the pipe.Rate this question:
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- 50.
The term "clarification" is most closely related to
- A.
all in-plant treatment processes.
- B.
purification
- C.
Sedimentation
- D.
The coagulation and flocculation processes
Correct Answer
C. SedimentationExplanation
Sedimentation is the process of separating solid particles from a liquid by allowing them to settle at the bottom. It involves the gravitational settling of particles in a suspension. Clarification, on the other hand, refers to the process of removing impurities or making something clear. Sedimentation is closely related to clarification as it is one of the key steps in the clarification process. During sedimentation, suspended particles settle down, resulting in a clearer liquid. Therefore, sedimentation is the most closely related term to clarification among the given options.Rate this question:
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Aug 27, 2024Quiz Edited by
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Sep 18, 2014Quiz Created by
Brandongebhart2