IF your printed the 8/29 lecture notes before 8/31, this material will appear there. I have since divided the notes at the point we reached by the end of class.

The Air/ The Atmosphere

• pressure drops as you climb
• Denver (5000 ft elevation) --
  • athletes need some extra conditioning
  • a lung of air has less oxygen
• Rocky Mountains (10,000- 12,000 ft)
  • you can still breathe normally (but carefully)
• Mt. Everest (xx ft)
  • most climbers finish with extra oxygen
• Aircraft
  • at xxx ft you need oxygen mask or
  • pressurized aircraft to survive
  • even here, the air is still nearly 20% O₂-- there's just less of it.

• they make the air unpleasant, unhealthy
• we refer to this as Air Pollution
  • suggests we (you, they) are the source
  • not a natural component
• not always true
  • some problem species come naturally
  • natural is not same as good/ benign
• volcanoes ; geothermal vents (SO₂, CO)
• forest fires (soot, CO, ...)
• trees, especially coniferous (hydrocarbons, haze)
• lightning (nitrogen oxides)
• bacterial decay ,skunks, etc (unpleasant stuff)

Carbon Monoxide, CO

• can kill at low concentrations
  • 1% = 1 part per hundred
  • 1 ppm = 1 part per million
• 5-20 ppm of CO is serious
• Numerical shorthand big and small numbers
  • 10, 10²=100 , 10⁵ = 100000
  • 10^-6 = 0.000001
  • 6.3 x 10⁴ = 63000

• CO mostly arises from burning C compounds
  • CH₄ = methane (natural gas)
  • CH₄ + O₂ ----> CO₂ + H₂O
  • There is an error on the next line, corrected in class
  • CH₄ + 3 O₂ ---> CO₂ + 2 H₂O
  • The corrected equation is below:
  • CH₄ + 2 O₂ ---> CO₂ + 2 H₂O
    • balanced equation, correct bookkeeping
    • CH₄ has 4 H; matched by 4H in 2 H₂O
    • 2 O ₂ has 4 oxygen; matched by 2 in CO₂ plus two in 2 H₂O
    • 1 C on each side (CH₄ and CO₂)
• if we restrict O₂, some is
• CH₄ + O₂ ----> CO + H₂O
• next line has also been corrected from the original notes
• 2 CH₄ + 3 O₂ ---> 2 CO + 4 H₂O
  • cars, coal fired electric plants, small gasoline engines, home furnaces, cigarettes--
  • small amounts of CO; more if not well maintained

What's The Problem with CO?

Need to look first at O₂ and body

• blood contains hemoglobin
• big molecule-- Iron atom (Fe) at center
• in O₂ rich area, the iron adds O₂
• this is the lungs
• as blood moves, the O₂ is carried along
  • perhaps 90-95% of hemoglobin takes its oxygen
• when blood reaches tissue/muscle
  • at lower oxygen concentration
  • Fe releases its oxygen
  • body uses the oxygen
• pumps blood/ hemoglobin back to the lung
• repeats (recycles)

• hemoglobin
• picks up CO in place of O₂
  • if there's not much CO
  • picks up very little CO
• but CO binds better than O₂
  • it isn't given up
  • so this hemoglobin is lost
  • unable to carry oxygen
• next breath costs a little more hemoglobin
• if we lose 20% of hemoglobin
  • might feel winded
  • tired by simple exertion
• if we lost 50% of hemoglobin
  • like major blood loss
  • could be lethal
• at 20 ppm in air, serious impairment
• at 100 ppm (0.0001%) die in 15 minutes
• Treatment-- Fresh air / oxygen isn't good enough
  • blood transfusion
  • at lower levels, can lose the CO over hours
• Safety rules / policies
  • CO detectors common in houses
  • EPA rules on car engines (allowed CO levels)
  • EPA rules on power plants
  • Avoid letting CO accumulate
    • (don't run engine in garage; ventilate)
  • Serious recent problems with house boats
    • engine can vent into sleeping areas

ethanol, MTBE

EPA rules for California

• led to 5-10% MTBE in gasoline
• MTBE leakage has now contaminated much California well water
• MTBE is now thought to be a carcinogen
  • cancer causing substance
• Ethanol-- due to way it is produced, uses more gasoline than it saves