Atmosphere Flashcards
(25 cards)
Define Atmosphere
A layer of gases surrounding the Earth that is retained by gravity
Layers of the Atmosphere
Troposphere, Stratosphere, Mesosphere, Thermosphere
Percentage of Each Gas in the Atmosphere
Nitrogen (78%)
Oxygen (21%)
Argon (0.9%)
Carbon Dioxide (0.04%)
Other (0.06%)
Composition of Earths Atmosphere
- No atmosphere, molten surface, very hot
- Atmosphere = composed of H & He, no oxygen
- Earth began to cool, volcanic activity released carbon dioxide, water vapor, methane, and nitrogen into the atmosphere.
- Water is brought to Earth through comets, water condenses into oceans.
- Carbon dioxide levels decrease as it dissolves into the oceans.
- The first bacteria evolves, oxygen appears in the atmosphere for the first time
- Primitive plant species appear on Earth, oxygen levels rise as carbon dioxide levels decrease in the atmosphere due to photosynthesis
- as fossil fuels and sedimentary rocks form some carbon gets locked in them.
How do you test for carbon dioxide?
If limewater turns from colourless to cloudy, carbon dioxide is present. Or you can apply a glowing splint and the splint goes out.
How do you test for oxygen?
Apply a lit splint, if it relights oxygen is present.
How do you test for water vapor?
Cobalt Chloride Paper turns from blue to pink.
What is the formula for complete combustion?
fuel + 02 –> CO2 + H2O
What is the source and effect of carbon monoxide?
source - fuels are burnt in limited oxygen
effect - carbon monoxide poisoning ( carbon monoxide replaces oxygen in the blood)
What is the source and effect of carbon dioxide?
source - released when fossil fuels are burnt
effect - enhanced greenhouse effect
What is the source and effect of methane?
source - intensive cow farming + rice paddy fields
effect - enhanced greenhouse effect
What is the source and effect of sulfur dioxide?
source - released when fossil fuels are burnt
effect - acid rain
What is the source and effect of nitrogen oxide?
source - released by car engines
effect - smog
What is the source and effect of nitrogen dioxide?
source - released by car engines
effect - smog + acid rain
What is the source and effect of particulates?
source - released when fossil fuels are burnt + present in petrol and paint
effect - nerve damage
What are some problems caused by the enhanced greenhouse effect?
- Ice caps melting - sea levels rise, flooding of coastal lines, loss of habitat for polar animals
- Deserts expanding - e.g. the Sahara desert has expanded by 10% since 1920
- Extreme weather - damage to crops, property, and habitats
What is the pH of normal rain water?
5.5
What is the pH of acid rain?
4 or higher
What is acid rain?
Acid rain is the man-made increase in acidity brought about by pollution of the atmosphere, mainly through the burning of fossil fuels.
What are some problems caused by acid rain?
Trees dying - leaves = damaged –> no photosynthesis
Aquatic life die - lakes and rivers become too acidic
Crops cannot grow - soil becomes too acidic
Buildings and statues made of sandstone or carbonate rocks erode
Corrosion of metal occurs faster
What is the natural greenhouse effect?
A natural process that warms the Earth and keeps it within habitable temperatures. Without it, Earth would have an average temperature of -19 degrees.
What is the enhanced greenhouse effect?
An enhanced version of the greenhouse effect where excessive heat is trapped around the Earth thus is increasing its temperature.
Define hydrocarbon
A compound made only of hydrogen and carbon.
Name 3 fossil fuels
Coal, oil, natural gas