C9: chem of atmosphere
Subdecks (1)
Cards (21)
- | the atmosphere
- 78% nitrogen
- 21% oxygen
- 0.04% carbon
- | the atmosphere
- earth = 4,600 million…
- scientists not sure about the early atmosphere
- 1st billion years: intense VOLCANIC activity = WATER VAPOUR, CO2, nitrogen, methane and ammonia
- earth cools = water vapour condense = oceans
- some CO2 dissolved in ocean = WEAK ACIDS which forms PRECIPITATES, creating sediments of CARBONATE rocks
- | the atmosphere
- some CO2 used to make corals/shells of organisms & when die, it created LIMESTONE
- this removes CO2!
- 2.7 billion years ago: photosynthetic algae evolved in ocean
- = oxygen & plants evolved = increase oxygen until animals could evolve
- reduced CO2 by taking it in
- carbon can be trapped in fossil fuels = decrease CO2
- | fossil fuels
- non-renewable
- COAL: remains of FERNS & TREES
- when die in WETLANDS = can’t decompose because lack of oxygen = bacteria cant decompose
- plant gets COMPRESSED + high temp & pressure = COAL
- | fossil fuels
- CRUDE OIL: PLANKTON REMAINS
- die, settles in mud_ dont compose if no oxygen present
- compressed by sediment & heat + pressure = CRUDE OIL
- | fossil fuels
- NATURAL GAS: mainly hydrocarbons & methane
- near deposits of oil because it’s from PLANKTON
- all fossil fuels have TRAPPED CARBON which is taken in by PHOTOSYNTHESIS
- | greenhouse effect
- amount of water vapour depends on TEMPERATURE
- water vapour, CO2, methane are greenhouse gases
- | greenhouse effect
- energy from sun travels to earth as SHORT WAVELENGTH RADIATION
- some REFLECTS back into space but most easily pass through atmosphere because wavelength NOT interact strongly with gas molecules & energy absorbed by surface
- surface of earth RADIATES energy as LONG WAVELENGTH & some interact w/ greenhouse gas molecules which causes energy to be absorbed
- due to energy being trapped in atmosphere, it causes temperatures to INCREASE
- greenhouse effect is USEFUL to keep temperature warm enough to support life