C9 - Chemistry Of The Atmosphere Flashcards
What is the present composition of the atmosphere?
78% nitrogen
21% oxygen
1% CO2/water vapour/noble gases
What is the start of the evolution of the atmosphere story? first 1 billion years
Intense volcanic activity releasing lots of CO2, water vapour! , nitrogen, ammonia, methane - little to no oxygen
What is step 2 in evolution of the atmosphere
Less volcanic activity - earth started to cool - water vapour CONDENSED to form oceans
What is step 3 in the evolution of the atmosphere?
First organisms developed which could perform photosynthesis - algae - releasing oxygen and taking in CO2
CO2 dissolved in the oceans + rock fell into th ocean, CO2 locked in rocks due to sediment packing it - locked in
Plankton died and were compressed into sediment - forming fossil fuels deep underground and locking in more carbon
What is stage 4 in the story of the atmosphere?
Earth has very little CO2 in the atmosphere - today - mostly nitrogen and some oxygen
We burn fossil fuels which have been formed by plankton dying
Explain how the greenhouse effect works in 3 stages
- Short wave (ultraviolet) radiation from the sun passes through atmosphere and warms earth[s surface
- Earth cools and emits long wave (infrared) radiation
- Greenhouse gases absorb long Timon and re emit it in all directions including back to earth, warming the atmosphere
What is the greenhouse effect
When gases such as CO2 absorb infrared radiation, warming earth
What is global warming
Gradual increase in earth’s temperature
Give 2 greenhouse gases that contribute to the greenhouse effect
CO2 + methane
Give 4 ways we contribute to greenhouse effect
Burning fossil fuels
Deforestation
Cattle farming (large scale)
Landfill
Give 2 ways we increase CO2 levels in atmosphere
Deforestation + burning fossil fuels
Give 2 ways we contribute to methane in the atmosphere
Cattle farming and landfill
Why does landfill produce methane
Decay of waste by micro organisms
Give 3 effects of global warming
Glaciers melting
Sea level rise
Extreme weather events like floods/droughts
Give 4 effects of climate change
Altered habitats
Changing temperature
Extreme weather events
Changes in rainfall affecting food production
Extinction of species
What is a carbon footprint
Total amount of CO2 given out over the life of a product/person
Give 4 ways to reduce carbon footprint
Eat less meat
Public transport
Turn off lights
renewable energy sources
What does sulphur dioxide cause
Acid rain
Respiratory problems
How is sulphur dioxide formed?
Sulphur in fuel reacts with oxygen in the air
What does CO do?
Toxic gas - colourless and odourless
What does soot(carbon particulates) do? x 2
Causes global dimming
health problems for humans
How is nitrogen oxide formed?
Nitrogen + oxygen from the air react at high temperatures
Give 2 things nitrogen oxides cause
Acid rain and respiratory problems
How are nitrogen/sulphur oxides released
Burning fuels that contain sulphur and nitrogen
What could acid rain lead to
Kill/erode vegetation
why is evidence about the early atmosphere limited
time scale of 4.6 billion years
at the start of the evolution of the atmosphere what was the earth’s atmosphere like - 1 billion years
mars or venus - mainly CO2 little to no oxygen
when did algae first produce oxygen
2.7 billion years ago
what 2 things produced the oxygen now in the atmosphere
algae and plants
give 2 ways CO2 was decreased in atmosphere
algae and plants doing photosynthesis
formation of sedimentary rocks and fossil fuels that contain carbon
how were crude oil and natural gas formed
algae died
buried under sediment
lack of oxygen so no oxidation
heat and pressure forms the oil and gas
what is limestone formed from
shells and skeletons of marine organisms
what is coal formed by
dead trees
buried with floods
prevented oxidation
pressure and heat turns it into coal
give 3 examples of greenhouses gases
water vapour
carbon dioxide
methane
how does greenhouse effect work
why is climate change accepted
ot is based on peer reviewed evidence
why is climate change sometimes not accepted
difficult to model such complex systems
leading to simplified models and speculations and opinions in media which may be based on only parts of the evidence and be biased
increasing average global temp causes what
climate change
