Earth and Atmosphere Flashcards
What percentage of the atmosphere today is made up of
nitrogen?
78%
What percentage of the atmosphere today is made up of
oxygen?
21%
What percentage of the atmosphere today is made up of
argon?
0.9%
What percentage of the atmosphere today is made up of
carbon dioxide?
0.037%
How long ago did cyanobacteria evolve?
2.7 billion years ago
What was so special about
cyanobacteria?
they were the first creature to photosynthesise
What is the equation for
photosynthesis?
carbon dioxide + water -> oxygen + glucose
6CO2 + 6H2O -> 6O2 + C6H12O6
Where is most of the carbon from the original carbon dioxided now locked up in?
- coal
- natural gas
- sedimentary rock
- oil
What are the causes of
carbon dioxide
as a pollutant in the air?
combustion
respiration
What are the causes of
sulfur dioxide
as a pollutant in the air?
burning of coal
(burning the sulfur impurities)
What are the causes of
carbon particulates (soot)
as a pollutant in the air?
burning wood and fossil fuels
What are the causes of
carbon monoxide
as a pollutant in the air?
incomplete combustion
What are the causes of
nitrogen dioxide
as a pollutant in the air?
internal high temperature combustion engines
(e.g. cars)
What effects on the environment does the air pollutant carbon dioxide have?
it reflects radiation back into the earth’s atmosphere - contributing to global warming
(and the greenhouse effect)
What effects on the environment does the air pollutant sulfur dioxide have?
It binds with water vapour in clouds to produce acid rain. This acid rain destroys forests, erodes limestone buildings and kills aquatic life.