Chemistry of the atmosphere

• 4.5 billion years ago 


  crust covered in volcanoes

  co2, water vapour, nitrogen
• 3.5 billion years ago 


  earth cooled condensing the water vapour forming seas water dissolved sulphur dioxide, ammonia and some co2 simple organism
• 2 billion years ago 


  photosynthesis caused rapid oxygen growth and absorption of co2
• 700 million years ago 


  simple animals formed from minerals in the sea
• 400 million years ago 


  plants colonised dead plants formed coal today
• 200 million years ago 


  proportions of gas stabilise
• sedimentary rock is formed 


  dissolves in ocean

  forms metal carbonates

  fall to the bottom of the ocean

  form’s sedimentary rock
• sedimentary rock is formed 


  co2 in the atmosphere

  taken in by plants and algae

  animals use carbon to make bones and shells

  animals die and have bones and shells

  bones and shells are compresses over millions of years
• coal is formed

  co2 in the atmosphere

  taken in by plants and algae

  plants die

  remains buried in mud and rock

  turn into coal
• crude oil and natural gas forms

  co2 in the atmosphere

  taken in by plants and algae

  algae dies

  remains buried in mud and rock

  turns to crude oil and natural gas
• greenhouse gas effect

  shorter waves solar radiation passes through earths atmosphere warming earth

  earth cools by emitting larger wavelength infrared radiation

  some of the infared radiation is absorbed by greenhouse gasses maintaining earths thermal energy

  increasing the amount of greenhouse gasses will result in more thermal energy being trapped
• causes of global warming 


  combustion of fossil fuels

  deforestation

  increased population leads to increased animals lead to increased methane
• primary effects of global warming

  increased atmospheric temperature

  polar ice caps melting

  more severe mansoons and droughts
• secondary effects of global warming

  sea levels rise because of melting ice caps

  extinction

  low lying areas will flood
• carbon monoxide

  toxic and odourless
• how is carbon monoxide produced

  produced by incomplete combustion
• what does carbon monoxide cause

  respiratory issues
• incomplete combustion equation 


  fuel + oxygen —> carbon monoxide + carbon + water
• how is carbon produced

  incomplete combustion
• what is carbon (soot)


  solid particles that builds up and appear black or dirty
• what does soot cause to the environment

  haze or global dimming
• what does soot cause to humans

  respiratory problems
• how are nitrogen oxides formed

  oxidation of nitrogen from the air at high temps in a vehicle engine
• what does nitrogen oxide cause

  acid rain
• what does acid rain result in

  break down from chemical erosion

  lakes being acidified

  changes in soil pH
• how is sulphur dioxide formed

  oxidation of sulphur
• what does sulphur dioxide cause

  acid rain
• how is carbon dioxide produced

  complete combustion (plenty of oxygen present, fuel is fully oxidised)
• what does co2 cause in the environment

  greenhouse gas so it contributes to global warming
• what can co2 cause in humans

  acid rain too much carbon dioxide can lead to respiratory problems
• complete combustion equation

  fuel + oxygen —> carbon dioxide + water
• what are direct emissions

  emmissions that you are aware of

  e.g. car or buses
• what are indirect emissions

  emissions that you have no control of or not aware of

  e.g. distance food travels
• what is a carbon offset

  a reduction in emissions of greenhouse gases made in or to compensate/offset on emissions made somewhere else