//c/1/./1// Flashcards
(13 cards)
- What is the atmosphere (air) that surrounds the Earth mainly made up of?
- Nitrogen (N)
- Oxygen (O)
- Argon (Ar)
- water vapour (H2O)
- carbon dioxide (CO2)
- What is air?
Air is a mixture of different gases consisting of small molecules with large spaces between them
- What are the approximate relative proportions of the main gases in the atmosphere?
78% nitrogen
21% oxygen
1% argon
- What can be released into the air that can affect air quality?
Other gases or particulates may be released into the atmosphere by human activity or by natural processes (e.g. volcanoes), and that these can affect air quality
- How was the earth’s early atmosphere formed?
The Earth’s early atmosphere was probably formed by volcanic activity and consisted mainly of carbon dioxide and water vapour
- What happened when the earth cooled?
Water vapour condensed to form the oceans when the Earth cooled
- What did the evolution of photosynthesising organisms do to the atmosphere?
photosynthesis takes up carbon dioxide (which was plentiful in the early atmosphere), and gives off oxygen
- How was carbon dioxide removed from the atmosphere?
-by dissolving in oceans
Lots of the early CO2 did this
-by forming sedimentary rocks
The carbon became ‘locked up’ in sedimentary rocks
-by the formation of fossil fuels
This came from plants that contained carbon that become buried in sedimentary rocks
- What can be added to the atmosphere by human activity that can change the composition of the atmosphere?
- carbon monoxide
- nitrogen oxides
(Mon/di) - sulfur dioxide
- extra carbon dioxide
- small particles of solids (e.g. carbon)
- What are pollutants?
substances that are harmful to humans
- Where do pollutants come from?
Burning fuels in power stations and vehicles
- What is a pollutant that is directly harmful to humans?
-carbon monoxide: reduces the amount of oxygen the blood can carry= flu like symptoms= death
- What is a pollutant that is directly harmful to the environment so can indirectly cause harm to humans?
- sulphur dioxide: acid rain= pollutes rivers= kills fish= humans can’t eat the fish
- carbon dioxide: climate change= rising sea levels etc.
