C11 The Earth's Atmosphere

Question 1

How did the earth’s atmosphere develop?

Answer 1

The atmosphere was mostly hydrogen and helium
Volcanoes produced co2, nitrogen and water vapour
Atmosphere similar to that of Venus today
Little or no oxygen

Question 2

How did the oceans develop

Answer 2

It may have rained for 40,000 years to create the oceans

Question 3

When did life evolve and how

Answer 3

3.4 billion years ago
Many theories as to how
2.7 billion years ago as simple plants and bacteria evolved oxygen was formed

Question 4

What is another theory about water arriving ?

Answer 4

Water could have come from space from comets containing lots of ice

Question 5

As plants increased what happened

Answer 5

More oxygen in the atmosphere

Animal life began to evolve that could not make their own food and relied on plants for food and oxygen to respire

Question 6

What are the main gases in the atmosphere

Answer 6

Nitrogen
Oxygen
Carbon dioxide
Argon
Water and other trace gases

Question 7

What is the role of nitrogen

Answer 7

78%
Always been in the air
Removed by nitrifying bacteria
No common test

Question 8

What is the role of oxygen

Answer 8

21%
Added by plants as product of photosynthesis
Removed by animals as product of respiration
Test - re lights a glowing splint

Question 9

What is the role of carbon dioxide

Answer 9

0.04%
Added as a product of animals respiring and industry
Removed by plants in photosynthesis and ocean uptake
Test by limewater - turns cloudy

Question 10

What is the role of argon

Answer 10

1%

Always in the air - product of radioactive decay

Question 11

What is the role of water and other trace gases

Answer 11

Varying small amounts
Added - water by evaporation
Removed by precipitation (rain)
Test - anhydrous copper sulphate turns from white to blue

Question 12

How does the carbon cycle work

Answer 12

Sunlight and co2 used in photosynthesis 
Dead organisms and waste products decay
Produce fossils and fossil fuels
Root and plant respiration take carbon from soil
Animal respiration releases co2
Auto and factory emissions release co2

Question 13

What about ammonia and methane?

Answer 13

Found in earth’s early atmosphere
Not in current atmosphere because
Ammonia- NH3(g)+ H2O(l) -> NH4OH (aq) ammonium hydroxide
Methane- CH4(g)-> CH4(aq) solution

Question 14

What are the main pollutants

Answer 14

Carbon dioxide
Sulphur dioxide
Nitrogen oxide 
Carbon monoxide 
Carbon particles

Question 15

Carbon dioxide- how it forms- problems it causes- solution

Answer 15

Formed by complete combustion of fossil fuels
Problem to the environment of global warming but no health problems as we breathe it out
Solutions- use vehicles less, more public transport, use biofuels

Question 16

Sulphur dioxide
How formed
Problems caused
Solution

Answer 16

Burning sulphur impurities in fuels
Problem to health:poisonous gas
Problem to environment: acid rain
Solution of flue gas desulphurisation in power stations

Question 17

Nitrogen oxides
How formed
Problems caused
Solutions

Answer 17

Burning nitrogen in high temperature in cars
Problem to health: can trigger asthma
Problem to environment: acid rain
Solution is catalytic converters

Question 18

Carbon monoxide
How formed
Problem
Solution

Answer 18

Incomplete combustion of fuels
Health problem; poisonous and reduces oxygen in blood
Environment problem:none
Solution; catalytic converters

Question 19

Carbon particles (Soot)
Caused
Problems
Solution

Answer 19

Incomplete combustion of fuels
Problems of health: lung damage possibly cancer
Problems of environment: global dimming
Solution: filters (especially in diesel cars)