Chemistry of atmosphere Flashcards
How long ago did the atmosphere form
4.6 billion years ago
explain the volcano theory on how the atmosphere formed
- Intense volcanic activity released the gases that form the atmosphere
- similar to Mars and Venus
how would the sea have formed
- Water vapour in the Earths atmosphere cools and condenses to form the oceans
what is the % Nitrogen in the atmosphere
78%
what is the % of oxygen in the atmosphere
21%
what is the % of other gases including argon in the atmosphere
1%
How did levels of oxygen increase in the early atmosphere
- algae produced oxygen – due to photosynthesis
- then population of algae slowly increased, producing more algae
when did algae first produce oxygen
2.7 billion years ago
How did levels of carbon dioxide decrease in the early atmosphere
- when the oceans formed, carbon dioxide dissolved in the water
- plants in the oceans (algae) also absorbed carbon dioxide for phtotsynthesis
what happened wen carbon dioxide dissolved in the sea
- this produced carbon compounds
- reducing the amount of Carbon dioxide in the atmosphere
- Carbon compounds were then precipitated
- an example of this would be limestone
How is crude oil formed
- Aquatic plants and animals die
- fall to bottom of sea, trapped under sand and mud
- overtime they’re buried deeper
- due to rising heats and pressure the lower they go
- they are turned into crude oil or natural gas
How is coal formed
- from giant plants that lived in swamps
- they die and sink beneath mud,water and soil
- over time, increased pressure and temps force the remains to undergo chemical and physical changes
- oxygen is pushed out and all that remains is coal
what has caused an increase in methane
- farming cattle
- farming rice
what causes an increase in carbon dioxide
- burning fossil fuels
- deforestation
what are the main greenhouse gases
- Carbon dioxide
- water vapour
- methane
How is global warming different to climate change
- global warming is how the Earth’s atmosphere has warmed up in the past 200 years
what is a carbon footprint
total amount of CO2 and other greenhouse gases over the full life cycle of a product
what might contribute to an individuals carbon footprint
- travelling abroad by plane
- driving cars or using public transport
- Heating a home
- food such as beef or rice
How are Nitrogen oxides produced
- in car engines
- when high temps and pressures
- forces nitrogen to react with oxygen
- producing Nitrous oxides
what do Nitrogen oxides cause
- acid rain
- photo chemical smog
- impacts on human health
why is acid rain bad
- erodes buildings
- damages plants
- kills fish
how is photochemical smog produced
nitrogen oxides in atmosphere react with ultra violet light from the sun
what is the problem of photochemical smog
- it impacts our health
- particularly affecting people who suffer with asthma
what is complete combustion
- when there’s enough oxygen for a fuel to burn
- a hydrocarbon will react with oxygen to produce carbon dioxide an water
what is incomplete combustion
- occurs when there isn’t enough oxygen for a fuel to burn
- it produces carbon monoxide and water and carbon particulates
- the reactants remain the same as complete combustion when you look the equation. It’s just the products that change
Why is carbon monoxide dangerous
- colourless
- odourless
- binds to haemoglobin in the red blood cells, preventing them from taking oxygen around the body
Why are carbon particulates bad
- irritates lungs
—> making asthma worse
—> increasing risk of cancer
What is global dimming caused by
Carbon particulates blocking out the sun’s rays + may reduce rainfall
How is sulfur dioxide produced
Burning fossil fuels
How does carbon dioxide harm the planet
- dissolve in rain water and form acid rain
- damage forests, plants, aquatic environments
- slowly erodes buildings + statues
