chemistry of the atmosphere Flashcards
composition of the atmosphere
nitrogen - 78% oxygen - 21% argon - 0.9% carbon dioxide - 0.04% other - 0.06%
test for hydrogen
use a lit splint, and it burns with a squeaky pop. 2 H2 + O2 -> 2 H2O
test for carbon dioxide
when bubbled through limewater, the limewater turns cloudy.
Ca(OH)2 + Co2 -> CaCO3 + H2O
test for oxygen
a glowing splint relights
test for chlorine
damp blue litmus paper is bleached (turned white) with Cl.
how was our early atmosphere produced?
intense volcanic activity high CO2 water vapour methane ammonia
NO OXYGEN
how long was the atmosphere unchanged for?
200 million years
how did co2 levels decrease?
- decreased volcanic activity
- dissolution in sea water
- evolution of algae and sea plants (photosynthesis)
- trapping of co2 in fossil fuels
- formation of carbonate & sedimentary rocks
what did co2 levels decreasing do?
increased oxygen levels
- photosynthesis
- formation of life!
what increases co2 levels?
- volcanic activity
- respiration of animals
- burning of fossil fuels
- organisms decaying
- animal digestions
main greenhouse gases
carbon dioxide - co2
methane - ch4
water vapor - h2o
how do greenhouse gases cause global warming?
- uv passes through the atmosphere to reach surface
- long, ir reduction from earth absorbed by greenhouse gases and reemitted into the atmosphere (tonic my g)
- this increases temperature
effects of climate change
- erratic weather
- unpredictable natural disasters
- distribution of wildlife
- ice caps melt
- demand / higher cost of food production
what is carbon footprint?
total amount of co2 and ghg emitted over the full life cycle of a product, service or event
how to reduce carbon footprint (7)
- carbon off setting, eg. plants and trees
- carbon storage and capture
- reduce reuse recycle (lifestyle change)
- alternative transport
- local buying reduces transport
- alternative agricultural practice
- renewable energy sources
