CHEM 110

Exam #3

Multiple Choice: 2 pts. Each

_____1. The stratosphere is the atmosphere layer where the following is the main component:

a) nearly all living things b) nearly all human activity

c) ozone layer d) most air pollution

_____2. Most ultraviolet rays do not reach the earth's surface after passing through the ozone layer because:

a) UV radiation is released when ozone decomposes

b) UV radiation prevents ozone from decomposing

_____4. Hemoglobin is the blood protein responsible for the transport of oxygen. Carbon monoxide disturbs oxygen transport by:

a) destroying hemoglobin

b) destroying oxygen in the lung

c) binding more strongly to hemoglobin than oxygen

_____5. London or industrial smog is attributed primarily to:

a) automobile exhaust b) the burning of coal

c) sunlight and nitrogen oxides d) ozone

_____6. Sulfur dioxide reacts with oxygen to form:

_____7. Removal of particulates from smokestack gases is accomplished by all of the following EXCEPT:

a) lime scrubber

b) cyclone separation

c) electrostatic precipitator

d) bag filtration

_____8. The reaction: 2 CaO (s) + 2 SO₂ (g) + O₂ (g) ® CaSO₄ (s)

is the basis of:

a) electrostatic precipitators c) particulate removal

b) flue gas desulfurization scrubbers d) cyclone separator

_____9. Which of the following is one of the principal components required for photochemical smog?

a) nitrogen oxides c) sulfur dioxide

b) carbon monoxide d) acid rain

_____10. Catalytic converters on automobiles do all of the following EXCEPT:

a) Rh catalyzes reduction reactions c) oxidize NO gas to N2 gas

b) Pt and Pd catalyze oxidation reactions d) oxidize CO to CO2

_____11. Which of the following is a SOURCE of photochemical smog?

a) ozone b) VOC's - unburned hydrocarbons

c) aldehydes d) PAN

_____12. Ozone in the troposphere is beneficial in screening out ultraviolet rays..

a) TRUE b) FALSE

_____13. CFCs are reactive in the troposphere and inert in the stratosphere.

a) TRUE b) FALSE

_____14. The impact of CFCs on the ozone layer is amplified by the fact that:

a) CFCs replicate in the stratosphere

b) CFCs decompose before reaching the stratosphere

c) chlorine radicals react with oxygen to produce many reactive intermediates

d) one chlorine radcal atom will lead to the decomposition of many ozone molecules

_____15. Greenhouse gases are gases that:

a) absorb incoming solar radiation

b) absorb infrared radiation and changes it to heat energy

c) help radiate outgoing infrared radiation from the

d) absorb ultraviolet radiation and cool the atmosphere

_____16. The climate modifying property of lakes and oceans is because of the water's:

a) density c) boiling point

b) high heat capacity d) surface tension

_____17. Which of the following is NOT related to the hydrogen bonding property of the water molecule?

a) density of ice

b) transpiration of water

c) heat of vaporization

d) boiling and melting points

_____18. If water behaved like other molecules with similar molecular weights, it would exist: (See Figure 10.5)

a) only in the gas state on earth at normal temperatures

b) only in the liquid state on earth at normal temperatures

c) only in the solid state on earth at normal temperatures

_____19. The amount of oxygen consuming wastes is a measure of the amount of:

a) dissolved oxygen in a water sample

b) anaerobic organisms in a water sample

c) oxygen required to degrade organic material in the water

d) oxygen required by aquatic life in a water sample

_____20. Which substance is likely to be produced when the dissolved oxygen in a lake is in sufficient supply?

_____21. Nitrates are a hazard in ground water because:

a) they are poisonous to humans

b) they are converted to nitrites in infants which damage hemoglobin in the blood stream

c) they are insoluble in water and difficult to remove

_____22. Which is NOT an effect of thermal pollution on aquatic organisms?

a) fish acquire several different diseases

b) there is an increase in the body temperature of fish

c) the dissolved oxygen content of the water decreases

d) the reproductive activity of fish may be altered

_____23. In the secondary stage of sewage treatment process oxygen from air is bubbled in primarily because

1. it can move around the bacteria
2. provide a crucial reactant for anaerobic bacteria to breakdown organic waste
3. provide a crucial reactant for aerobic bacteria to breakdown organic waste
4. to sweep out the carbon dioxide from the water

_____24. 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) is more expensive than other approaches

d) produces low levels of carcinogenic chlorinated hydrocarbons

_____25. The Aral Sea in central Asia is drying up because:

a) there has been very little rain for a long time

b) water has been drained from the lake to support several cities

c) water has been diverted from rivers that flow into the lake so it can be used for irrigation

1. farmland has been reclaimed from the lake

26. a)(4) Briefly define and explain the causes of ACID RAIN-(include some specific chemicals by name and formula and reactions, if possible). See p. 150-51, 193-96, 330, 333-334

b)(3) Then list/explain some consequences of the problem (What things are adversely effected?)

c)(3) Finally propose some very specific solutions to the problem. How can it be prevented? p. 334

27. (9) (See p. 284-289.) a. List and define 3 unique or "abnormal" properties of water. (Ice density counts as one property.)

b. What structure of water and bonding property is responsible for some of these abnormal properties?

c. Explain the environmental or climate consequences of these properties.

28. (9) Water pollutants can be divided into different categories as considered in Chapter 10. (See p. 294-306). Choose THREE categories listed below and briefly discuss them.

b. effects on the environment

c. steps to control them or cleanup

Choose ANY THREE from below:

Disease Causing Agents

Oxygen-consuming wastes

Nutrients and Eutrophication

Pollution of Ground Water

Toxic Substances

29. a)(6) A major goal of sewage treatment is to reduce the amount of organic waste which is released to a natural water body. Explain how this is accomplished in primary and secondary treatment. Include at least all of the following terms such as oxygen, bacteria, sludge, aerobic. See p. 306-308.

30. (3) One approach to increasing fresh water supply in water deficient areas near sea water sources is desalination. Explain the process of REVERSE OSMOSIS used for desalination and the energy problems and costs related to them. p. 293-94

Associated Press Chicago Tribune

b)(2) What health effects are possible if the ozone concentration is depleted?

e)(5) The newspaper article does not do a good job of explaining the chemistry of the ozone hole. Continue to add to the article to explain why the ozone hole develops. Use some words and/or equations as found in your text to help with this. (P. 340-343.)

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Ozone hole is bigger, thinner, riskier

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UN researchers say UV shield loss could last longer

By Erica Bulman

Associated Press

October 4, 2003

GENEVA -- The ozone hole over the South Pole is as large as it has ever been and lasting longer this year, heightening concern about harmful UV radiation reaching Earth, the United Nations weather organization said Friday.

Compounding matters, the thinnest area is the largest ever measured, about two-thirds of the hole's total size, the World Meteorological Organization said.

"The ozone hole is getting larger, deeper and is lasting longer," said Michael Proffitt, a leading expert on the ozone hole at the UN agency. "It has never stayed this large, this late."

The "hole" is a thinner-than-normal area in the protective layer of gas high in the atmosphere. It has formed in August--the end of the Antarctic winter--every year since the mid-1980s, largely due to chemical pollution.

In recent years, the hole has tended to reach its maximum size about mid-September, after which it mostly gets refilled with surrounding ozone.

But this year the hole peaked twice, once in mid-September and again later in the month, the weather organization said. Each time it measured 10.8 million square miles, matching the record size set in September 2000.

The hole could last longer still, Proffitt said.

"There is certainly no indication it is getting smaller," he said. "It looks like it could be awhile."

Reduction of the ozone layer can let harmful ultraviolet rays from the sun reach Earth's surface. Too much UV radiation can cause skin cancer and destroy tiny plants at the beginning of the food chain.

The UN weather organization said that although the large ozone hole is persisting, UV intensity over Antarctica will remain low until the sun rises higher during the Southern Hemisphere's spring.

"The longer it lasts, the more effect you get from UV," Proffitt said. "When the sun is low, the UV rays slant through on an angle and have to go through a thicker layer.

"But as you go into the Antarctic's spring and the sun rises higher, more UV rays can get directly through the hole."

The weather organization also said the thinnest part--with the ozone level 50 percent below the pre-ozone hole period of 1964-76--exceeded 5.7 million square miles for the first time. It peaked near 6.95 million square miles Sept. 26. That is two-thirds of the ozone hole.

Proffitt said it was too soon to conclude what the significance of this year's larger weak spot would be.

Earth has lost more ozone in the past than this year, he said. In some years, while the thin spot was smaller, it contained even less ozone, which is produced naturally when sunlight combines with oxygen high in the atmosphere.

The sun triggers accelerated ozone loss when it starts to rise again over Antarctica after the dark South Pole winter.

One cause of ozone depletion is the chlorine and bromine released by chemical compounds, such as chlorofluorocarbons, contained in some aerosols and refrigerants.

Chlorofluorocarbon emissions have been curbed under a global accord. As a result, measurements show they are now decreasing in the lower atmosphere and have just peaked and stabilized in the crucial ozone layer in the stratosphere.

Scientists predict it will take about 50 years for the ozone hole to stop forming.