evolution of the atmosphere

Question 1

when was the earth formed

Answer 1

4.6 billion years ago

Question 2

what was the earth like for the first billion years

Answer 2

a molten ball of rock with many volcanoes releasing gases

Question 3

what planets are looked at to gather this information

Answer 3

venus and mars

Question 4

what did volcanoes release

Answer 4

carbon dioxide water vapour and nitrogen

Question 5

what happened to the water vapour

Answer 5

condensed and fell as rain

Question 6

what did the early atmosphere consist of

Answer 6

mainly carbon dioxide and some water vapour and nitrogen. Traces of methane ammonia and oxygen.

Question 7

when did life begin

Answer 7

3.4 billion years ago

Question 8

what evolved around 2.7 billion years ago

Answer 8

bacteria and algae they could now photosynthesise

Question 9

what did photosynthesis mean

Answer 9

oxygen in the atmosphere slowly increased and more organisms evolved

Question 10

what is the formula for photosynthesis

Answer 10

6CO2 + 6H2O –> C6H12O6 + 6O2