Air Quality

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Air Quality
(OCR)
W Richards The Weald School
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The Earths Atmosphere
Present day atmosphere contains 78 nitrogen, 21
oxygen, 1 noble gases and about 0.03 CO2
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Pollution
Humans pollute the Earth in a number of ways
Pollutant Harmful to... Why?
Carbon dioxide Environment
Nitrogen oxides Environment humans
Sulfur dioxide Environment
Particulates (e.g. Smoke) Environment humans
Carbon momoxide Humans
A greenhouse gas that causes global warming
Causes acid rain and makes asthma/breathing
problems worse
Causes acid rain
Makes buildings dirty and makes asthma worse
Displaces oxygen in red blood cells that can
result in death
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Measuring pollution
Low concentration
High concentration
Concentration is measured in Parts per Million
(ppm) or Parts per Billion (ppb).
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Some sample data
Location Time Carbon monoxide concentration (ppm)
London 9am 11am 1pm 3pm 5pm 6.4 6.2 5.9 3.1 6.3
The Cotswolds 9am 11am 1pm 3pm 5pm 0.2 0.2 0.1 0.2 0.1
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Elements
If a solid, liquid or gas is made up of only one
type of atom we say it is an element. For
example, consider a tripod made up of iron
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Compounds
Compounds are different to elements. They
contain different atoms. Here are some examples
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Some simple compounds
Carbon dioxide, CO2
Water, H2O
Ethyne, C2H2
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Simple chemical reactions
Water
H2O
Magnesium sulphate
MgSO4
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Burning Fuels Combustion
Lots of oxygen
Methane
Some oxygen
Little oxygen
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Other products of burning fuels
Sulphur dioxide
Nitrogen monoxide
Nitrogen dioxide
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Pollution
What happens to pollution?
Carbon dioxide causes global warming but some of
it can be removed by plants (photosynthesis) or
reactions with seawater.
Sulfur dioxide and nitrogen dioxide cause acid
rain which damages trees and buildings.
Particulates (like in smog) can make buildings
dirty and worsen breathing difficulties.
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Removing Pollution
There are many ways pollution can be reduced

• Use less electricity/central heating
• Remove toxic chemicals before or after they are
  burnt
• Use alternative energy sources, e.g. wind power

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Reducing Pollution from vehicles
A number of suggestions
1) Buy a new, smaller, cleaner car
2) Buy a hybrid car
3) Convert your car to run on biodiesel
4) Make sure your car has a catalytic converter
5) Use the train or a bus!
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Making choices about pollution
Choices concerning fighting pollution can be made
on many levels

• International
• e.g. The Kyoto protocol in 1997

• National
• e.g. Car tax system, subsidies for greener
  technology

• Local
• e.g. Recycling schemes, transport, congestion
  charges

• Personal
• e.g. Recycling, individual travel, reducing
  energy usage in the home etc