Reminder exam one Friday review questions from Chapters 1-4

Transcription

1 Reminder exam one Friday review questions from Chapters 1-4 CHAPTER ONE REVIEW QUESTIONS 1. Which three gases cons>tute most of the Earth s atmosphere? a. CO 2, NO 2 and NO b. H 2 O, H 2, O 3 c. CH 4, CH 2 O, OH d. N 2, O 2, Ar 2. What range of al>tudes cons>tutes the troposphere? The stratosphere? a. 0 5 miles and 5 15 miles b miles and miles c. 0 9 miles and 9 30 miles d. Less than 1 mile and greater than 1 mile 3. What is the wavelength range for visible light? Does UV light have shorter or longer wavelengths than visible light? a nm; longer b nm; shorter c nm; longer d nm; shorter

2 4. Which atmospheric gas is primarily responsible for filtering out sunlight in the nm region? Which gas, if any, absorbs most of the Sun s rays in the nm region? Which absorbs primarily in the nm region? a. CO 2, CO, O 2 b. CO, SO 2, NO 2 c. O 2, O 3, nobody d. O 2, N 2, O 3 7. What is meant by the expression photochemically dissociated as applied to stratospheric O 2? 11. Explain why the phrase ozone layer is a misnomer. 14. What is mean by the term steady state as applied to the concentra>on of ozone in the stratosphere? 16. Explain why ozone destruc>on via the reac>on of O 3 with atomic oxygen does not occur to a significant extent in the lower stratosphere

3 CHAPTER TWO REVIEW QUESTIONS 1. What is a Dobson unit? How is it used in rela>on to atmospheric ozone levels? a. 1 DU = the thickness of pure ozone at the density it would have at 1 atm and 0 C (that thickness would be 0.01 mm). Average thickness = 350 DU or 3.5 mm b. 1 DU = the thickness of pure ozone at the density it would have at 5 atm and 100 C (that thickness would be 0.01 mm). Average thickness = 350 DU or 3.5 mm c. 1 DU = the thickness of pure ozone at the density it would have at 1 atm and 0 C (that thickness would be 0.01 mm). Average thickness = 100 DU or 1.0 mm d. 1 DU = the thickness of pure ozone at the density it would have at 5 atm and 100 C (that thickness would be 0.01 mm). Average thickness = 100 DU or 1.0 mm 3. Describe the process by which chlorine becomes ac>vated in the Antarc>c ozone hole phenomenon. See Figure 2 4, pp Explain why full scale ozone holes have not yet been observed over the Arc>c 6. What are two effects on human health that scien>sts believe will result from ozone deple>on? a. Increases in skin cancer and adverse effects on the human immune system b. Increases in pulmonary diseases and heart abacks c. Increases in asthma and diabetes d. Increases in leukemia and arthri>s

4 9. What types of chemicals are proposed as long term replacements for CFCs? a. Hydrocarbons b. HCFCs c. HFCs d. Oxides of nitrogen 10. Chemically, what are halons? What was their main use? a. Oxygen containing hydrocarbons; fuels b. Bromine containing hydrogen free substances (e.g. CF 3 Br); fire ex>nguishers c. Sulfur containing fuels such as coal; hea>ng and genera>on of electricity d. Asbestos containing compounds; insula>on 11. What gases are being phased out according to the Montreal Protocol agreements?

5 CHAPTER THREE REVIEW QUESTIONS 1. In the micrograms per cubic meter concentra>on scale, to what substances do micrograms and cubic meters refer? 2. In general terms, what is meant by photochemical smog? What are the ini>al reactants in the process? Why is sunlight required? a. light induced chemical reac>on of pollutants; NO, VOCs; free radical forma>on b. Smoke and fog; CO, CO 2 ; alkenes c. PM 2.5 ; coal dust; free radical forma>on d. PM 10 ; NO x ; even electron species 3. What is meant by a primary pollutant and by a secondary pollutant? Give examples. a. Species that are anthropogenic; species that are natural; O 3 vs. VOCs b. Species directly emibed into the air; substances into which primary pollutants are transformed; NO, VOCs vs. O 3 and HNO 3 4. What is the chemical reac>on by which thermal NO is produced? From which two sources does most urban NO arise? What is meant by the term NO x? 5. Describe the strategies by which reduc>on of urban ozone levels have been abempted. What difficul>es have been encountered in these efforts?

6 8. What are the main anthropogenic soures of sulfur dioxide? Describe the strategies by which these emissions can be reduced. What is the Claus reac>on? a. Nuclear fuels; proper storage of spent fuel rods; reduc>on of uranium b. Cigarebe smoke; filtering the smoke; oxida>on of CO to CO 2 c. Burning of gasoline; cataly>c converters containing Pt; oxida>on of CO to CO 2 d. Coal and crude oil; pre and post combus>on cleaning; conversion of sulfur to its elemental form 10. Describe the various strategies used to produce clean coal a. Burn coal at a higher temperature b. Remove S prior to combus>on; react SO 2 with CaCO 3 ; remove NO by cataly>c reduc>on to N 2 c. Remove nitrogen prior to combus>on

7 CHAPTER FOUR REVIEW QUESTIONS 2. What is acid rain. What two acids predominate in it? a. Hydrofluoric and hydrocyanic acids b. Ace>c and formic acids c. Oxalic and nitric acids d. Sulfuric and nitric acids 7. Describe the major health effects of outdoor air pollutants. 8. List four important reasons why coarse par>cles usually are of less danger to human health than are fine par>cles 1. Cannot penetrate deep into lungs 2. Large par>cles rapidly seble out of the air 3. Are typically from the breakup of larger par>cles rather than from chemical reac>ons 4. Smaller par>cles contain a larger organic content and in many areas are acidic 9. What are the main sources of formaldehyde in indoor air? What are its effects? 10. What are the main sources of nitrogen dioxide and carbon monoxide in indoor air? Of benzene?