The Evolution of the Atmosphere
This lesson covers:
- The formation of the early atmosphere by volcanic activity
- How the atmosphere changed with the formation of the oceans
- How living organism made the atmosphere more suitable for life
Roughly how old is the planet Earth?
Around 2.7 billion years old
Around 13.7 billion years old
Around 4.6 billion years old
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Which gas makes up around 80% (78.09% to be exact) of the Earth's atmosphere?
Carbon dioxide
Nitrogen
Oxygen
Argon
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Which gas makes up around 20% (20.95% to be exact) of the Earth's atmosphere?
Nitrogen
Carbon dioxide
Argon
Oxygen
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Which of the gases below contribute less than 1% to the Earths atmosphere?
(Select all that apply)
Carbon dioxide
Oxygen
Argon
Nitrogen
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In the first billion years, the gases that formed Earth's early atmosphere came mainly from which source?
Burning of fossil fuels
Volcanic activity
Photosynthesis by plants and algae
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During the first billion years, which two of the following gases were released from volcanoes?
Oxygen
Water vapour
Carbon dioxide
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Cooling of the Earth
dissolved / cool / warm / sediments / condense / oceans / carbonates
- Around a billion years after it formed, the earth began to . This allowed water vapour to into liquid water and form the .
- When the oceans formed, carbon dioxide in the water, and were precipitated, producing .
- Steps 1 & 2 dramatically reduced the amounts of water vapour and carbon dioxide in the atmosphere.
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Starting 2.7 billion years ago, which process started to increase the amount of oxygen in the atmosphere, and further decreased the amount of carbon dioxide?
Photosynthesis by plants and algae
Volcanic activity
Burning of fossil fuels
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Complete the word equation for photosynthesis:
carbon dioxide + ➔ oxygen +
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As photosynthetic organisms such as plants and algae died, the carbon they contained became trapped in rocks, and fuels.
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