C9 - Chemistry Of The Atmosphere Flashcards
Phase 1 of evolution of the atmosphere
Volcanoes gave out gases
Early atmosphere was mainly carbon dioxide and virtually no oxygen
Volcanic activity released nitrogen - this built up as well as water vapour and small amounts of methane and ammonia
Phase 2 of evolution of atmosphere
When water vapour condensed, it formed oceans
Lots of CO2 removed from early atmosphere as it dissolved in oceans - CO2 went through series of reactions to form carbon precipitates - formed sediments on sea bed.
Green plants and algae evolved and absorbed CO2
Marine animals evolved - skulls and skeletons contained carbonates from ocean
Some carbon these organisms took in from oceans and atmosphere locked up in rocks and fossil fuels after organisms died
Plants, plankton, marine animals die fall to seabed and get buried by layer of sediment. Over millions of years, become compressed and form sedimentary rocks , oil and gas - trap carbon
Coal, crude oil and gas made from this
What are crude oil and gas formed from
Plankton deposits
What is coal made from
Plant deposits
Phase 3 of evolution of atmosphere
Absorb CO2 in atmosphere - produce oxygen through photosynthesis. Carbon dioxide + water -> glucose + oxygen
Algae evolved first then green plants
As oxygen built up, new life forms could evolve
200 mil years later it’s us 80% nitrogen , 20% oxygen and little of other gases like CO2, noble gases and water vapour
What are greenhouse gases
Gases like CO2, methane and water vapour act like an insulating layer in the earths atmosphere to allow earth to be warm enough
What do green house gases do
They absorb long wavelength radiation that’s reflected off earth and re-radiate it in all directions and back to earth - thermal radiation which warms earth ‘greenhouse effect’
What affects the amount of greenhouse gases
Deforestation - fewer trees = less CO2 removed from atmosphere
Burning fossil fuels - locked up carbon release as CO2
Agriculture - more farm animals produce methane through digestive system
Decomposition of waste - more CO2 and methane released
How is increasing CO2 linked to climate change
Earths temperature increasing due to extra CO2 from human activity
Consequences of climate change
Increase in temperature - polar ice caps melt and increase sea levels - flooding on low level lands and coastal eroding
Loss of habitat
Change in rainfall patterns - cause regions to get too much or too little water
Temperature change - harder to produce food
Change in temperature and water - affect wild species, affecting distribution
What are carbon footprints
Measure amount of CO2 and methane are released over the full life cycle of something
Difficult as there’s many factors to consider - making - disposal - sourcing
Ways of reducing carbon footprints
Renewable resources or nuclear energy instead of fossil fuels
More efficient processes could conserve energy and cut waste (waste produced methane(
Governments put cap on emissions on green house gases
Governments tax companies/individuals based on greenhouse gases they emit
Tech that captures CO2 before its released and outs back into ground
Why are carbon footprint gases difficult to reduce
Lots of work to be done to tech
Government worried change will impact economic growth - bad for wellbeing and development
Hard to make international agreements - don’t want to sacrifice economic developments
Hard to change lifestyles
What do fossil fuels contain and how does this affect combustion
Contain hydrocarbons - carbon and hydrogen oxidised during combustion - CO2 AND water vapour released
Solid particles of soot (carbon) and unborn fuel are released and carbon monoxide and CO2 produced
What problems do particulates cause
If inhaled, stuck in lungs and cause damage
Respiratory problems
Bad for environment
