56) About ________ of the world’s fresh water supply is used in agriculture.
A) 10%
B) 45%
C) 85%
D) 70%
57) Ppm and ppb are
A) toxic chemicals.
B) chlorinated hydrocarbons.
C) wastewater treatment strategies.
D) concentration units.
58) The EPA drinking water standard for toluene is 3 mg/L. What is this concentration in ppm?
A) 0.003
B) 0.3
C) 3
D) 3000
59) The EPA drinking water standard for toluene is 1 mg/L. What is this concentration in ppb?
A) 0.001
B) 0.1
C) 1
D) 1000
60) The EPA drinking water standard for arsenic is 0.050 mg/L. What is this concentration in ppb?
A) 0.050
B) 5.0
C) 50.
D) 5.0 × 103
61) The EPA drinking water standard for arsenic is 0.040 mg/L. What is this concentration in ppm?
A) 0.040
B) 4
C) 40
D) 4000
62) One of the potential problems with chlorination of waste water is that it
A) provides no residual protection.
B) is ineffective against pathogenic bacteria.
C) produces low levels of chlorinated hydrocarbons.
D) is more expensive than other approaches.
63) One of the advantages of treating sewage effluent with ozone as opposed to chlorine is
A) O3 is more effective in killing viruses.
B) O3 is more effective in killing bacteria.
C) O3 provides a residual protection against bacteria.
D) O3 is less expensive.
64) Aeration of drinking water
A) removes odors.
B) increases dissolved air.
C) improves flavor.
D) does all of the above.
65) Fluorides are added to water to
A) kill viruses.
B) remove nitrites.
C) neutralize bases.
D) prevent tooth decay.
66) Municipal water supplies are generally treated either with chlorine or with ozone. Which of the
following statements is true?
A) Chlorine is more expensive.
B) Ozone provides residual protection against microorganisms.
C) Ozone does not kill viruses.
D) Ozone is more expensive, but less of it is needed.
67) Municipal water supplies are disinfected by treatment either with chlorine or with ozone. One
advantage which chlorine has over ozone is that
A) chlorine treatment kills viruses and ozone does not.
B) chlorine treatment converts dissolved organic compounds into chlorinated hydrocarbons.
C) chlorine leaves a taste in the water.
D) chlorine continues to provide protection against microorganisms even after the water leaves the
treatment plant.
68) Which of the following is considered to be a disadvantage of fluoridating drinking water?
A) The concentration of fluoride in drinking water is usually 0.7-1.0 ppm.
B) Some hydroxide ions in tooth enamel are replaced by fluoride ions.
C) High fluoride consumption in early childhood can cause mottling of the teeth.
D) Treatment with fluoride results in harder tooth enamel.
69) Bottled water is becoming an increasingly popular drink in the United States. Which of the following
statements about bottled water is true?
A) All bottled water comes from natural springs and artesian wells.
B) The testing of bottled water is generally less rigorous than the testing of municipal water supplies.
C) Bottled water contains almost no dissolved ions.
D) Bottled water is less expensive than tap water.
70) Which of the following statements about bottled drinking water is true?
A) Bottled water is safer than tap water.
B) Bottled water is healthier than tap water.
C) Bottled mineral water often contains more dissolved ions than tap water.
D) All bottled water comes from natural springs or artesian wells.
71) Primary sewage treatment involves
A) aeration.
B) settling.
C) chemical treatment.
D) Primary sewage treatment involves all of the above.
72) Secondary treatment of sewage involves
A) filtering and aeration.
B) settling and sludge removal.
C) chlorination.
D) Secondary sewage treatment involves all of the above.
73) In secondary treatment of sewage, which removes organic matter?
A) chlorine
B) ozone
C) aluminum sulfate and lime
D) aerobic bacteria
74) Secondary treatment of wastewater is not effective for removal of
A) suspended matter.
B) dissolved organics.
C) nitrates and phosphates.
D) bacteria.
75) Charcoal filtration of wastewater is an excellent method for the removal of
A) dissolved ions.
B) organic molecules.
C) nitrates and phosphates.
D) sludge.
76) Advanced treatment of wastewater can include any of the following EXCEPT
A) charcoal filtration.
B) sand and gravel filtration.
C) phytoremediation.
D) reverse osmosis.
77) Many communities are beginning to use sludge on farm fields. What is the biggest problem with
using sludge on fields?
A) The sludge must be dried before it can be applied to the fields.
B) Wet sludge may irrigate the crops.
C) Sludge is often contaminated with toxic metals that could be taken up by plants.
D) Sludge is a source of nutrients and humus.
78) What percentage of public water supplies in the United States do NOT meet one or more of the EPA
water standards?
A) 1 %
B) 25 %
C) 10 %
D) 70 %
14.2 True/False Questions
1) You can live for weeks without food, but only days without water.
2) The volume of water increases as it freezes.
3) The density of ice is greater than the density of liquid water.
4) Most of the water available on the earth’s surface is potable.
5) The principal cations in hard water are sodium and potassium ions.
6) Acid rain is a major problem for lakes with a limestone bedrock.
7) Acid rain results in the release of more magnesium ions from soil.
8) Nitrate contamination of water is more common in farming areas than in urban areas.
9) Industries in the United States have significantly reduced their contribution to water pollution in recent
years.
10) Zeolites are solids and much more easily removed than catalysts that are dissolved in the reaction
mixture.
11) Zeolites can often be regenerated simply by soaking them in a salt solution.
12) Mesoporous zeolites have pore diameters that are less than 2 nm, while microporous zeolites have pore
diameters that are between 2 nm and 50 nm.
13) The major use of water in the United States is for public water supplies.
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14) A concentration of 4.2 mg/L is the same as 4.2 ppb.
15) A possible new technology for disinfecting drinking water involves using ultraviolet light.
16) Ozone treatment of the water supply is effective against viruses.
17) Bottled water generally has fewer dissolved ions than tap water.
18) The fastest growing segment of the beverage industry is bottled water.
19) Most water bottles are recycled.
20) The Clean Water Act has had no impact on water quality over the past two decades.
21) Phytoremediation is the use of plants to remove metals or other contaminants.
22) Each person in the United States flushes approximately 8,000 L of drinking quality water down the
toilet each year.
23) Water pollution can be completely eliminated by tripling our current funding for Clean Water Act
initiatives.
14.3 Short Answer Questions
1) Ice is ________ (less/more) dense than liquid water.
2) What are two relatively unique physical properties of water? What impact do these properties have on
life on Earth?
3) The heat capacity of water is ________ (greater/less) than that of ethanol.
4) Water has a relatively ________ heat capacity.
5) Why is it virtually impossible to find pure water on Earth?
6) It is estimated that approximately ________ people in the world do not have an adequate supply of
fresh water and ________ live without basic sanitation.
7) VOC stands for ________.
8) Under aerobic conditions, microorganisms ________ organic matter; under anaerobic conditions,
microorganisms ________ organic matter.
9) A stagnant pond has an odor like ammonia. This is a good indication that the BOD of the pond is
________ and that the DO is ________.
10) To use clean water is to abuse it. Each of us can do our share by ________ water and ________ our use
of products that require vast amounts of water to make.
14.4 Essay
1) How do the unique properties of water allow for life on Earth?
2) Describe how water is capable of moderating the temperature of the Earth.
3) Describe how the water cycle acts to purify water.
4) Nitrates contaminate many wells in agricultural areas. Why?
5) Once groundwater is contaminated, it is very difficult to purify. Discuss this problem of groundwater
sources of water with respect to the water cycle.
6) Describe the phytoremediation of sewage treatment.
