Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Chemistry of the Atmosphere > Flashcards

Chemistry of the Atmosphere Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

What are the proportions of gases in the air?

A

80% Nitrogen
20% Oxygen
small proportion of other gases: Carbon dioxide, water vapour, noble gases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why is evidence for the early atmosphere and its formation limited?

A

Due to the time scale of 4.6 billions years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a theory of the formation of the early atmosphere?

A

During first billion years of Earth’s existence
- intense volcanic activity, released gases forming the early atmosphere
- released water vapour-> condensing into oceans
- volcanoes produced nitrogen: gradually built up in atmosphere, also small proportions of methane and ammonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What was the Earth’s atmosphere like during the beginning of the period of the atmosphere forming?

A

Earth’s atmosphere similar to current Mars or Venus atmosphere (mainly CO2, little oxygen)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

During the formation of the atmosphere, what happened when oceans formed?

A
  • Carbon dioxide dissolved into the water
  • ## Carbonates precipitated-> produced sediments, reducing amount of CO2 in atmosphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the photosynthesis equation?

A

6CO2 + 6H2O -> C6H12O6 + 6O2

produced by algea and plants during the formation of the early atmosphere-> increasing oxygen, decreasing carbon dioxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How did the percentage of oxygen in the atmosphere gradually increase?

A
  • first produced oxygen around 2.7 billion years ago-> began appearing in atmosphere
  • over next billion years: plants evolved, % of oxygen increased
  • eventually enabled animals to evolve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How did levels of Carbon dioxide decrease in the early atmosphere?

A
  • algea and plants due to photosynthesis
  • formation of sedimentary rocks and fossil fuels that contain carbon
  • dissolved into oceans-> reacted to form carbon precipitates that formed sediments on the seabed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are Greenhouse Gases and what do they do?

A

Maintain temperatures in the atmosphere on Earth to support life

  • Water vapour, Carbon dioxide, Methane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How are fossil fuels formed?

A

Crude oil and natural gas- deposits of plankton, form thick reservoirs under the seabed

Coal- sedimentary rock made from thick plant deposits

Limestone- sedimentary rock, calcium carbonate deposits from shells and skeletons of marine organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does plants, plankton and marine animals dying lock carbon away?

A
  • the organisms die and sink to the seabed
  • then get buried under layers of sediment
  • become compressed and form sedimentary rocks, oil and gas over millions of years
  • trapping carbon within- reducing CO2 levels in the atmosphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the evidence from volcanoes for the evolution of the early atmosphere?

A
  • Gases released by volcanoes today are similar to volcanoes that erupted billions of years ago
  • gives evidence as to what gases were present in the early atmosphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the evidence from other planets for the evolution of the early atmosphere?

A
  • Atmosphere of planets where there is no life (Mars, Venus etc)
  • Can be used to predict what atmosphere might have been like before life evolved.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the evidence from rocks for the evolution of the early atmosphere?

A
  • Certain rocks called ‘Red beds’ contain lots of iron oxide.
  • Can only form when there is enough oxygen in the atmosphere to react with iron
  • Age of red beds can be used to predict at which point oxygen levels reached a particular level in the atmosphere.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the evidence from living things for the evolution of the early atmosphere?

A
  • Some simple organisms (ie early bacteria), DONT rely on reactions involving oxygen to release energy
  • Use other gases (ie carbon dioxide)
  • Fossils of bacteria have been found which are older than fossils of creatures that depend on oxygen
  • Implies life first evolved without need for oxygen, so not much in the early atmosphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the Greenhouse effect?

A
  • The sun emits short wavelength radiation, which passes through the earth’s atmosphere, and isn’t absorbed by greenhouse gases
  • Short wavelength radiation reaches the Earth’s surface, is absorbed, then reemitted as long wavelength radiation
  • This radiation is absorbed by greenhouse gases in the atmosphere
  • Then the gases re-radiate in all directions, including towards earth
  • Longwave radiation= thermal radiation-> results in the warming of the surface of the earth (the greenhouse effect)
17
Q

How is more carbon being added to the environment and less being removed?

A
  • human population is rapidly increases-> becoming more industrialised
  • burning more fossil fuels-> releasing carbon
  • cutting down forests-> no longer absorbing carbon for photosynthesis
18
Q

How has the global population increases led to the increase of carbon in the atmosphere?

A
  • more food needs to be produced-> methane levels rising (ie cows, paddy fields for rice)
  • more waste-> more landfill, which can break down and release more CO2 and METHANE
19
Q

What do most scientists agree on about the effect of extra greenhouse gases in the atmosphere?

A
  • extra greenhouse gases in the atmosphere due to human activity
  • cause an increase in temperature-> will lead to climate change

this evidence has been peer reviewed, so is reliable

20
Q

Why is it hard to understand the earth’s climate? What has this led to?

A
  • complex and many variables
  • hard to make a model that isn’t over simplified
  • speculation on climate change and its impact-> speculation happens in the media (biased or misinformed storied)
21
Q

What are some consequences of climate change?

A
  • Increase in global temperature-> polar ice cap and glaciers melting, causing a rise in sea levels, increasing flooding in coastal areas and coastal erosion
  • Changes in rainfall patterns (timing, amount, distribution)-> may cause some regions to get too much or too little water
    Along with changes temp-> can affect regions ability to produce foods
  • Increase in frequency and severity of storms
  • Changes in temperature and amount of water available in a habitat-> affects wild species, leading to differences in distribution
22
Q

Why is it important that scientists communicate new evidence to a wide range of people?

A
  • climate change can affect everyone on the planet
  • people can be informed, then they can decide how to act in response to climate change
23
Q

What do climate change policy makers need to consider?

A

How many people might be affected-> some changes affect fewer people than others (living inland= unlikely to be affected by coastal erosion) OR can affect masses (area important for global food production, if crops dont grow-> millions of people affected)

What impact the change could have->
- Short term= severe blizzards disrupt transport links BUT snow melts
- Long term= rising sea levels could permanently flood towns or cities close to the sea

24
Q

What are Carbon Footprints?

A

measure of the amount of carbon dioxide and other greenhouse gases released over a full life cycle.

25
Q

Why is measuring a carbon footprint difficult?

A

Many different factors to consider

  • however can make a rough calculation
26
Q

What are methods to reduce carbon footprints?

A
  • use renewable energy sources or nuclear sources (instead of burning fossil fuels)
  • develop more efficient processes that use less energy (less fossil fuels need to be burnt)
    Processes that produce less waste= less greenhouse gas emissions (less decomposing into methane gas)
27
Q

How can the government encourage people to reduce emissions?

A
  • tax companies or individuals based on amount of greenhouse gases emitted
  • place cap on amount of greenhouse gases a company could make + sell licenses for emissions up to the cap
  • Bills businesses pay for electricity, natural gas and coal are taxed-> encourages to use more energy efficient processes
  • Some businesses have to pay tax on amount of waste sent to landfill (UK)
28
Q

How can technology be used to reduce carbon footprints?

A
  • technology that captures CO2 produced by burning fossil fuels BEFORE its released into the atmosphere
  • then can be stored deep underground in cracks in rock (old oil wells etc)
    = CARBON CAPTURE AND STORAGE
29
Q

What are issues with reducing carbon footprints?

A
  • Governments, using caps and taxed on emissions could reduce economic growth of communities (especially for developing countries)
  • Hard to make international agreements to reduce carbon emissions
  • Reducing carbon footprints= costly, less profits for businesses
  • People making changes (walking and cycling instead of car) is hard to enforce.
    Lack of knowledge on the subject or interest means they won’t change
30
Q
A

Chemistry (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions