Atmospheric Chemistry

• Troposphere - closest to earth's surface, where weather occurs, air pressure decreases with altitude, temp decreases with height
• The atmosphere is the gaseous envelope surrounding Earth, consisting mainly of nitrogen (78%), oxygen (21%), and trace amounts of other gases.
• Compositions of Ambient Air (Highest density to Lowest)

  1. Nitrogen
  2. Oxygen
  3. Argon
  4. Neon
  5. Helium
  6. Kronium
  7. Xenon
• Mesopause - boundary between mesosphere and thermosphere
• Stratopause - boundary between stratosphere and mesosphere
• Nobel Prize in Chemistry (1995) - Robert H. Grubbs

  • formation and decomposition of ozone
• Venus - most alike with the earth's atmosphere

  -presence of CO2 and N2
• Structure of the Atmosphere

  • thin layer of gas that wras the earth
  • gases are held closely because of gravity
• Photosynthesis - combination of water (H2O and CO2) to have glucose/ starch (C6H12O6) and Oxygen Gas (O2)
• Layers of the Atmosphere

  • troposphere
  • stratosphere
  • mesosphere
  • thermosphere
  • exosphere
  • ionosphere
• Troposphere

  • tropos means change (greek)
  • constantly changing or moving
  • 10-15 km high (Mt. Everest climbs to only 8.85 km high)
  • contains 75% of earth's atmosphere
• Stratosphere

  • 18-50 km high
  • contains the ozone layer (main constituent is Ozone - O3)
  • where aircrafts fly because of calm weather
  • temperature ranges from -56to -2 degrees C
• Mesosphere

  • meso means middle in greek
  • the coldest layer (temperature drops to -95 degrees)
  • 50-85 km high
  • main components are oxygen, nitrogen,dioxgenyl(02+) ions,nitrosonuim ion (NO+)
• Thermosphere

  • thermo - heat, sphaira - sphere
  • 85-500 km
  • temperature can rise up to 1200 degrees C
  • hottest layer
  • satellites and radio waves travel here
• Exosphere

  • exo - outside, external
  • uppermost layer at 1600 km high
  • air is extremely thin
  • Hydrogen gas and helium is its main constituents
• Ionosphere

  • made up of ions and electrons
  • not a layer but a region located between meso and thermo
  • Aurora - borealis (northern lights)-greenland, canda & norway; australis (southern)-antarctica, new zealand & australia
• Functions of the Atmosphere:

  -maintains heat balance

  -absorbs infrared rays

  -constituents are O,CO2,N
• Oxygen - essential for cellular respiration (ATP)