C1 - Air quality Flashcards
Dry air contains
21% -
Oxygen O2
Dry air contains
1% - And small amounts of other gasses
Argon (Ar)
oxygen gas + most metal =
Solid metal oxides
Dry air contains
78% -
Nitrogen (N2)
When was the earths atmosphere formed?
4 billion yrs ago
How was the atmosphere formed?
- Gasses came from the volcanoes
- As the atmosphere cooled the gasses condensed forming the sea.
- 3 billion yrs later bacteria evolved (photosynthesis) removing the CO2 from the atmosphere.
How are fossil fuels made?
Dead plants and animals are buried. As they get buried deeper under more dead animals and plants the pressure grows fossil fuels are eventually made.
How was sedimentary rock formed?
Carbon dioxide dissolve in the sea reacts with the salt = calcium carbonate. This forms sediment, which gets buried and cemented. Forming sedimentary rock.
Examples of fossil fuels
Gas, oil, coal
What are pollutants?
Gasses that are harmful to your health.
e.g. Carbon dioxide/ monoxide, nitrogen oxides, sulphur dioxide
Examples of polutants
e.g. Carbon dioxide/ monoxide, nitrogen oxides, sulphur dioxide
What are particulates?
Particles released from burning fuel that float in the air. E.g. Carbon (soot)
What makes acid rain?
Sulphur dioxide + nitrogen = acid rain
Sulphur dioxide in the air can trigger…
Asthma
What does ppm/ ppb stand for?
Parts per million/ billion
Only contains Carbon + hydrogen atoms:
Hydrocarbons
Give examples of hydrocarbons
Petrol
Diesel
Fuel oil
Hydrocarbons + oxygen =
Carbon dioxide + water (+energy)
+ O2 =
Oxidisation
- O2
Reduction
O2 reaction =
Combustion
What happen to atoms in a reaction?
They can rearrange but not change.
In a reaction atoms of non- metal elements join to form to make
Molecules
What happen to elements in a reaction?
They rearrange = new compound
Reactants are rearranged to new products with different properties.
- It is an indirect polutant
- When burned it produces a colourless gas
- can be found in coal
What is it?
Sulphur
How is carbon monoxide formed?
When a fuel is burned but there is not enough O2 available. - at a very high temperature.
What pollutants do car engines let out?
Nitrogen oxide
Carbon dioxide …
NO and NO2 are both found in the atmosphere, which one makes acid rain?
NO
What is Wet scrubbing
What is it called when sulphur dioxide is removed from power station waste, using the alkaline slurry, gypsum ( calcium +water)
Or sea water ( natural alkaline)
What is flue gas desulphurisation?
Removing sulphur dioxide from waste gasses.
Does gas or coal produce more carbon dioxide?
Coal
What do catalytic converters do?
Allow pollutant gasses to react with each other. CO+ NO = N+CO2
Which is less harmful.
What is it called when sulphur dioxide is removed from power station waste, using the alkaline slurry, gypsum ( calcium +water)
Or sea water ( natural alkaline)
Wet scrubbing
What was it that gave scientists evidence to say the early atmosphere was mostly made up of co2?
Recent rock composition discoveries.
What did scientist 60 yrs ago think the early atmosphere was made up of?
Ammonia and methane.
How is CO2 measured? What are other pollutant gasses measured in?
In parts per million (ppm)
1ppm = there is 1 gram of pollutant substance in 1million grams of air.
Other pollutants are measured in parts per billion (ppb)
Give an example of pollutants which affect us directly and indirectly
Directly= carbon monoxide poisoning Indirectly= acid rain harms the enviro. But affects our crops.
What are some pros of using pure oxygen to react with a fuel?
Burns rapidly.
Burns at a higher temperature.
What happens to the mass in a chemical reaction?
Stays the same because the atoms are just rearranging.
Give 5 the properties of sulphur:
- yellow solid
- colourless gas
- insoluble
- sulphur dioxide dissolved in rain = acid rain
- coal contains the most sulphur
Why do air quality measurements vary?
Results vary due to the conditions and varying weather.
E.g. Dry, hot, calm days = pollutants are trapped in the city.
What is incomplete combustion?
A reaction with insufficient oxygen.
Carbon monoxide and particles are formed during incomplete combustion. It is toxic.
What was it that gave scientists evidence to say the early atmosphere was mostly made up of co2?
Recent rock composition discoveries.
What did scientist 60 yrs ago think the early atmosphere was made up of?
Ammonia and methane.
