earth’s atmosphere

Question 1

what processes removed CO2 from the atmosphere?

Answer 1

• dissolving
• photosynthesis
• fossilisation
• sedimentation

Question 2

where did the nitrogen come from?

Answer 2

the ammonia (NH3) reacted with oxygen to form H2O and N2

Question 3

early atmosphere properties:

Answer 3

• hot
• lots of volcanic activity
• CO2 90%
• has ammonia, methane, little water
• NO OXYGEN

Question 4

today’s atmosphere properties:

Answer 4

78% nitrogen
20% oxygen
0.04% CO2
H2O

Question 5

how did the oceans form?

Answer 5

the planet cooled, H2O condensed

Question 6

explain how CO2 left the atmosphere

Answer 6

• dissolves into oceans
• used in photosynthesis of photosynthetic microbes underwater, produce oxygen
• plants above water too
• locked up in fossil fuels, used making seashells
• can make sedimentary rock