Chemistry in Context
Ozone
Good Up High, Bad Nearby
Gases in the atmosphere absorb certain wavelengths of solar radiation. If the radiation is sufficiently energetic, electrons involved in bonding are disrupted breaking covalent bonds to initiate important chemical changes. In this forum assignment, you will learn more about the interaction of sunlight with the atmosphere. Ozone is a naturally occurring trace gas found in the atmosphere. Sunlight plays a crucial role in its formation and decomposition. Ozone is both “good” and “bad” depending on what region of the atmosphere it is found. Ozone is essential in the upper atmosphere but a pollutant at surface levels. You will investigate how ozone can be both an air pollutant and necessary component in earth’s atmosphere as well as how ozone levels are being altered by human activity.
ASSIGNMENT:
1. Read the EPA publication “Ozone – Good Up High Bad Nearby” and at least two other resources listed below to learn more. These publications review and summarize the science, environmental issues and health concerns about ground level ozone pollution and the depletion of stratospheric ozone. They tell us that earth’s ozone layer protects people from harmful solar radiation and warns that ozone is an air pollutant. These seem like contradictory concerns.
◦ Ozone – Good Up High Bad Nearby (http://www.epa.gov/oaqps001/gooduphigh/): This is a fairly comprehensive introduction to ozone pollution and the depletion of the ozone layer.
◦ Ground Level Ozone Homepage (http://www.epa.gov/air/ozonepollution/) : Basic information about ground level ozone pollution and links to other EPA resources
◦ Ground Level Ozone Basic Information (http://www.epa.gov/air/ozonepollution/basic.html): EPA fact sheet about ground level ozone
◦ Brief Questions and Answers on Ozone Depletion (http://www.epa.gov/ozone/science/q_a.html): EPA question and answers factsheet addressing ozone depletion science and policy
◦ Helpful pages from Chemistry in Focus (5e):
◦ Section 9.10, “Smog,” pg. 238 - 240
◦ Section 11.7, “Air Pollution: An Environmental Problem in the Troposphere,” pg. 285 - 287
◦ Section 11.9, “Ozone Depletion: An Environmental Problem in the Stratosphere,” pg. 289 – 292
2. Answer the following questions:
◦ Explain the difference between the effects of ground level ozone and stratospheric ozone.
◦ Do we want ozone in our air or don’t we? Why is one beneficial to human life, while the other is not
◦ Which is the more serious environmental concern in your opinion? Surface ozone pollution or ozone layer depletion? Again, there is no “right” answer. Be sure to stick to the facts and avoid political ideology. Use the information you learned in the your reading and in lecture to support your opinion. Be prepared to defend your position.
3. Post your responses to these questions on the Ozone