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Question 1

How do volcanes affect the shaping of the earth?

Answer 1

Volcanoes in the early earth erupted and released lots of gases. Might be how early atmosphere formed. Early atmosphere probably mostly carbon dioxide, with virtually no oxygen. Volcano activity aslo released nitrogen, which built up in atmosphere over time, as well as water vapour and small amounts of methane and ammonia.

Question 2

what happened on the early earth with oceans, algae and co2?

Answer 2

When water vapour in atmosphere condensed, forms oceans. Lots of co2 removed from early atmosphere as dissolved in oceans. Dissolved co2 went through series of reactions to form carbonate precipitate4s that formed sediments on seabed. Green plants and algae evolved and absorbed some of co2 so could carry out photosynthesis. Marine animals evovled, their shells and skeletons contained carbonates from oceans. Some of carbon these organisms took in from atmosphere and oceans became locked up in rocks and fossil fuels after died. Green plants and algae produced oxygen in photosynthesis

Question 3

How did algae impact on teh early earth?

Answer 3

Algae evolved aswell as green plants. Oxygen levels buit up in the atmosphere over time, more complex life could evolve. 200 million years ago, atmosphere reached a composition similar to today 80%nitrogen, 20%oxygen, small amounts of other gases mainly co2, noble gases and water vapour.