Water Flashcards
The dramatic temperature changes on the moon between day and night are not seen on the earth because of what property of water?
high heat capacity
In secondary treatment of sewage, which removes organic matter?
aerobic bacteria
The saltiness of the oceans is
constant
Charcoal filtration of wastewater is an excellent method for the removal of
organic molecules
All of the following statements are true of hard water EXCEPT
A) charcoal filtration.
B) sand and gravel filtration.*
C) reverse osmosis.
D) phytoremediation.
The majority of fresh water is found in
polar ice caps
Primary sewage treatment involves
settling
Biochemical oxygen demand (BOD). is a measure of the amount of
oxygen required to degrade organic material in the water.
Water use is an important aspect of water conservation. For drinking purposes the average adult needs to consume about
1.5 L/day.
Advanced treatment of wastewater can include any of the following EXCEPT
A) charcoal filtration.
B) sand and gravel filtration.*
C) reverse osmosis.
D) phytoremediation.
One of the potential problems with chlorination of waste water is that it
produces low levels of chlorinated hydrocarbons.
Aerobic decomposition of organic matter requires
oxygen
The most serious threat to human health from water supplies is
bacteria
A major source of groundwater contamination is leaking underground storage tanks. Most of these tanks once held
gasoline
Which of the following is NOT a property of water?
A) It has a high specific heat.
B) It has a higher density in the liquid state than in the solid state.
C) It has a lower density than most liquids do.*
D) It dissolves most ionic substances.
One of the advantages of treating sewage effluent with ozone as opposed to chlorine is
O3 provides a residual protection against bacteria.
B) O3 is less expensive.
C) O3 is more effective in killing viruses.*
D) O3 is more effective in killing bacteria.
Which part of the water supply is most isolated from the purifying capacity of the water cycle?
groundwater
Approximately what fraction of the earth’s surface is covered with water?
75%
A major contaminant in well water in many agricultural areas is
nitrates
At any given time, what proportion of the world’s hospital beds are occupied by people with waterborne diseases?
50%
The Clean Water Act has had no impact on water quality over the past two decades.
false
Heat of vaporization is the amount of heat required to
evaporate a liquid
Anaerobic degradation of organic material in water systems occurs in the absence of
dissolved oxygen
Rainwater is
slightly acidic because it reacts with dissolved CO2 gas