1. Development Of The Atmosphere

Question 1

State a way in which carbon dioxide is removed from the atmosphere.

Answer 1

Evolution of photosynthesising bacteria and aglae

Question 2

Name two polluting gases in our atmosphere

Answer 2

Methane
Carbon Dioxide

Question 3

What 2 processes maintain the relatively stable levels of gases in our atmosphere

Answer 3

Respiration
Photosynthesis

Question 4

The earths earliest atmosphere was formed by

Answer 4

Volcanic activity

Question 5

State the four main gases present in the atmosphere today, and their percentages

Answer 5

Nitrogen=78%
Oxygen=21%
Argon=0.9%
Carbon dioxide=0.04%

Question 6

Name 2 events that have led to major changes in the composition of the earths atmosphere

Answer 6

Volcanic activity
Earths cooling (causes condensation of water vapour)

Question 7

Which force keeps the earth’s atmosphere in place

Answer 7

Gravity

Question 8

Describe why water vapour levels decreased in the atmosphere

Answer 8

The earth cooled down therefore the water vapour condensed into the sea

Question 9

Describe why levels of nitrogen increased in the atmosphere

Answer 9

During the volcanic eruptions nitrogen was released, but nitrogen is a very Unreactive gas, therefore its concentration gradually builds up

Question 10

Describe why oxygen levels increased in the atmosphere

Answer 10

The evolution of photosynthesising bacteria and algae

Question 11

What are the two experiments to determine the level of oxygen in the atmosphere

Answer 11

Copper in gas syringes
Red phosphorus

Question 12

Describe red phosphorus the experiment

Question 13

Describe the experiment of copper in gas syringes

Answer 13

Two syringes on both sides of a tube with copper in the middle with a Bunsen burner under it and the glass