Topic 9 - Chemistry of the Atmosphere

Question 1

What percentage of the early atmosphere was CO2 and what did it decrease to?

Answer 1

70% in the early atmosphere to 0.04% today

Question 2

What was produced by volcanoes in the early atmosphere?

Answer 2

Ammonia, methane and CO2

Question 3

What percentage was ammonia, methane and water at in the early atmosphere?

Answer 3

10%

Question 4

Give the balanced equation for ammonia reacting with oxygen

Answer 4

4NH3 + 3O2 –> 2N2 + 6H2O

Question 5

How was oxygen first produced in the atmosphere?

Answer 5

Algae started to photosynthesise using the CO2 already present

Question 6

Why did the amount of ammonia reduce in the atmosphere?

Answer 6

It reacted with oxygen to produce nitrogen and water and was no longer produced by volcanoes

Question 7

What percentage of the atmosphere today is nitrogen?

Answer 7

78%

Question 8

Give the balanced equation for methane reacting with oxygen

Answer 8

CH4 + 2O2 –> CO2 + 2H20

Question 9

How long did it rain for when the water vapour in the atmosphere condensed?

Answer 9

20 million years

Question 10

What percentage of the atmosphere today is oxygen?

Answer 10

21%

Question 11

Give four reasons why the amount of CO2 in the atmosphere decreased

Answer 11

1. Dissolved into oceans
2. Used by plants in photosynthesis
3. Trapped in fossil fuels
4. Trapped in hydrocarbons

Question 12

Name the five main atmospheric pollutants

Answer 12

1. Carbon dioxide
2. Carbon monoxide
3. Sulphur dioxide
4. Nitrogen oxides
5. Carbon particulates

Question 13

How is carbon dioxide produced and what problems does it cause?

Answer 13

Produced by complete combustion of hydrocarbons or fossil fuels and it contributes to the enhanced greenhouse effect

Question 14

How is carbon monoxide produced and what problems does it cause?

Answer 14

It is produced by incomplete combustion of hydrocarbons and it causes serious health repercussions for humans, it binds to haemoglobin in a person’s bloodstream and does not unbind causing respiratory distress

Question 15

How is sulphur dioxide produced and what problems does it cause?

Answer 15

Caused by sulphur impurities in fossil fuels which are burnt, it can bind with water and oxygen in the atmosphere to form acid rain

Question 16

What repercussions does acid rain have?

Answer 16

It destroys crops and has a bad effect on humans health

Question 17

How are nitrogen oxides produced and what problems do they cause?

Answer 17

They are produced in car engines when nitrogen and oxygen react in the high temperatures of a car engine and they also form acid rain in the atmosphere

Question 18

How are carbon particulates produced and what problems do they cause?

Answer 18

Produced at the same time as carbon monoxide and they cause global dimming and also lung cancer amongst other health problems in humans

Question 19

Give five ways in which we can reduce the production of atmospheric pollutants

Answer 19

1. Plant more trees
2. Use electric cars
3. Remove sulphur impurities
4. Reduce use of fossil fuels
5. Reduce incomplete combustion

Question 20

What is the average carbon footprint of a person in the UK?

Answer 20

10,000 kg per year

Question 21

What is the international average carbon footprint in the UK?

Answer 21

4,000 kg per year

Question 22

Give four ways we can reduce our carbon footprint?

Answer 22

1. Insulation and smart metres to save energy
2. Switch to electric cars
3. Use sustainable methods of transport
4. Buying local produce