Chemistry of the atmosphere Flashcards
The relative amounts of different gases in the Earth’s atmosphere has ——————- for the past couple of hundred million years.
stayed quite consistent
The relative amounts of different gases in the Earth’s atmosphere has stayed quite consistent for the past couple of hundred million years:
- 78% nitrogen
- 21% oxygen
- Small amounts of other gases (e.g. noble gases, carbon dioxide and water vapour)
Main gases in the Earth’s atmosphere :
- water vapour
- carbon dioxide
- noble gases
- oxygen
- nitrogen
The Earth was formed roughly ————- years ago.
4.6 billion
The Earth was formed roughly 4.6 billion years ago. We don’t have much evidence from that long ago, but the common view (consensus view) among scientists is:
- Age of the volcanoes
- Reduction of carbon dioxide levels
Highly active volcanoes were littered across the Earth’s surface for the ———— of its existence.
first billion years
The frequent eruptions of these volcanoes resulted in the …
release of lots of carbon dioxide (as well as smaller amounts of gases such as water vapour, methane, ammonia and nitrogen).
Scientists think carbon dioxide dominated the early atmosphere in a similar way to …
modern-day Mars.
Scientists think —————— dominated the early atmosphere in a similar way to modern-day Mars.
carbon dioxide
Levels of atmospheric nitrogen have …
accumulated steadily.
The oceans were formed as a result of the …
water vapour condensing.
The formation of the oceans caused a …
significant reduction in carbon dioxide levels in the atmosphere.
Carbonate precipitates were produced by ——————. These precipitates were deposited as sediment.
reactions between the dissolved carbon dioxide and seawater.
Carbonate precipitates were produced by reactions between the dissolved carbon dioxide and seawater. These precipitates were deposited as …
sediment.
Name the 2 gases with the largest proportions in the modern atmosphere.
- oxygen
- nitrogen
——————————- were produced by reactions between the dissolved carbon dioxide and seawater. These were deposited as sediment.
Carbonate precipitates
Photosynthesis is the process in which …
light energy is used to produce glucose and oxygen from carbon dioxide and water.
Photosynthesis increased the atmospheric concentration of …
oxygen
Algae were the first photosynthetic organisms to evolve. This happened about ———- years ago.
2.5-2.7 billion
Photosynthesising plants then began to evolve over the next billion years. This led to an ever-increasing rate of …
oxygen accumulating in the atmosphere
More complex life forms, such as animals, began to evolve once …
a threshold concentration of oxygen was reached.
What caused the oxygen levels in the atmosphere to increase?
Photosynthesis
What is needed for photosynthesis to take place?
- Carbon dioxide
- light energy
- water
So, the photosynthetic action of algae and plants removed ————— from the atmosphere.
carbon dioxide
The formation of oceans removed large amounts of —————- from the atmosphere.
carbon dioxide
The evolution of marine animals removed ———- from the oceans as the animals used these to build their shells and skeletons.
carbonates
At least 3 factors caused atmospheric carbon dioxide to decrease:
- Photosynthesis
- Oceans
- Marine animals
Greenhouse gases cause the greenhouse effect. This helps …
keep the Earth warm enough for life.
But, the greenhouse effect can cause …
global warming if it’s too strong.
The process of the greenhouse effect is:
- The Sun emits short-wavelength radiation that enters the atmosphere and travels towards the Earth.
2 .The Earth absorbs a portion of this radiation, but longer wavelength radiation is reflected back into the atmosphere. - Greenhouse gases can’t absorb the short wavelength radiation emitted by the Sun, but they can absorb the reflected radiation.
- The gases re-radiate this as heat energy, some of which heads back to Earth.
- This increases the temperature at the Earth’s surface.
Which region on Earth do you think reflects the greatest proportion of radiation arriving from the Sun?
The white surface of Antarctica makes it the most reflective region in the world.
This is one of the reasons why it’s so ridiculously cold!
Certain human activities cause the atmospheric concentrations of greenhouse gases to increase:
- Burning fossil fuels
- Agriculture
- Deforestation
- Landfill sites
Burning fossil fuels releases carbon, in the form of carbon dioxide. This carbon dioxide had been stored away for …
millions of years previously.
Farm animals release ——— during digestion.
methane
As the global population continues to rise, the scale of agriculture is ————. This means that more methane is being released into the atmosphere by livestock.
increasing
As the global population continues to rise, the scale of agriculture is increasing. This means that …
more methane is being released into the atmosphere by livestock.
As we cut down more and more trees, the global rate of photosynthesis will …
decrease
Given that carbon dioxide is a reactant in the equation for photosynthesis, this means that less carbon dioxide will be …
removed from the atmosphere by this process.
The number and size of landfill sites is …
increasing
Landfill sites release ———— , which is a greenhouse gas.
methane
Why is it important to maintain satisfactory levels of greenhouse gases on earth?
- Without greenhouse gases, temperatures would be too low to support life.
- However, high concentrations of greenhouse gases cause temperatures to rise too high, which also threatens life on Earth.
Although the temperature at the Earth’s surface naturally ———- , the recent increase in temperature is connected to increasing atmospheric greenhouse gas concentrations.
changes
The current scientific consensus is that increased greenhouse gas emissions caused by changes to human activity will lead to …
global climate change.
The current scientific consensus is that increased greenhouse gas emissions caused by changes to human activity will lead to …
Global climate change
The current scientific consensus is that increased greenhouse gas emissions caused by changes to human activity will lead to global climate change.
This consensus is based upon …
peer-reviewed evidence.
The global climate system is very complicated. This makes it difficult to create …
accurate models.
The global climate system is very complicated. This makes it difficult to create accurate models.
Because of this, people speculate about climate change based on …
simpler models and inadequate (not enough or not reliable) information.
Some people may have reasons to play down the contribution of greenhouse gas emissions to climate change.
If these biased opinions are published in the media, ———- can spread.
misinformation
What reasons might people have to play down the contribution of greenhouse gas emissions to climate change?
- A common bias is that an individual is involved in an industry which relies on, for example, burning fossil fuels.
- Burning fossil fuels is central to this individual’s profession but it is also known to release lots of carbon dioxide, which is a greenhouse gas.
- Therefore, it is in the individual’s interest to play down the negative effects of greenhouse gases in order to avoid more regulation of the relevant industry.
The melting of polar ice caps would cause:
- Sea levels to rise, leading to flooding and erosion of our coastlines.
- Some species to be less successful hunters (e.g. the polar bear).
Increasing the average global temperature is a significant reason for global climate change. The potential consequences are severe and wide-ranging:
- Melting of polar ice caps
- Meteorological events
- Changes in water availability
- Changes in precipitation
- Food shortages
Due to increasing the average global temperature, extreme meteorological events, such as …
storms, heatwaves and droughts, could increase in frequency and intensity.
Due to increasing the average global temperature, changes in water availability could affect how …
species are distributed.
Due to increasing the average global temperature, he quantity, the timing and distribution of precipitation could change. This would result in …
some regions receiving much less or much more rainfall than they previously did.
Due to increasing the average global temperature, a combination of some or all of these factors could hinder a region’s ability to …
produce food. This could lead to potential famines.
Possible consequences of global warming:
- Melting of polar ice caps
- Increased extreme meteorological events
- Changing water availability
- Changes in precipitation
- Food shortages
How could global climate change affect extreme meteorological events?
- Increased frequency
- Increased severity
The melting of polar ice caps would cause a rise in sea levels, leading to the flooding and erosion of ——— regions.
coastal
You can reduce your carbon footprint by:
- Maximise the efficiency of your energy use.
- Minimise your waste.
- Using renewable energy sources as an alternative to burning fossil fuels.
A carbon footprint is a measure of the total amount of …
greenhouse gases emitted as a result of a particular service, product or event.
Governments can reduce carbon footprints by imposing:
- Emission-based taxes.
- Emission caps.
- Emissions licenses up to a certain cap (these must be bought).
Carbon capture and storage refers to the …
capture of carbon dioxide produced by burning fossil fuels before it passes into the atmosphere.
Carbon capture and storage refers to the capture of carbon dioxide produced by burning fossil fuels before it passes into the atmosphere.
Stores of this captured carbon are then kept…
deep underground.
We can counteract emissions by planting trees, which will remove ——- dioxide from the atmosphere through the process of photosynthesis.
carbon
Carbon-neutral products don’t change the …
atmospheric carbon dioxide concentration.
The following are ways that we can minimise carbon footprints:
- carbon footprint
- Carbon capture and storage
- Carbon off-setting
- Carbon-neutral products
Many governments worry that making the required changes may …
restrict the economic development of their country.
Many governments worry that making the required changes may restrict the economic development of their country.
This attitude is most common in …
developing countries.
Scientists don’t agree on the causes and consequences of climate change.
This is preventing scientists from …
making significant advances.
Countries have different opinions about the right course of action.
This spreads uncertainty. Countries aren’t sure what other countries would do when presented with a potential international agreement.
Therefore, countries …
hesitate to sign anything.
People in developed countries might not want to change their lifestyles.
Some societies don’t make progress as their people are …
not educated on the importance of changing lifestyles.
Name the following barriers to reducing carbon footprints.
- Scientific disagreements
- Resistance to lifestyle changes
- Insufficient education
- economic development
What do we call products that don’t change the atmospheric carbon dioxide concentration?
Carbon-neutral products
Governments can reduce carbon footprints by imposing…
- emission-based taxes
- emission caps
- licenses for emissions up to a certain cap
Burning fossil fuels is a major cause of air pollution. Burning fossil fuels produces lots of …
carbon dioxide, as well as smaller quantities of other pollutants.
When fossil fuels are burned in a confined space, the high temperatures can cause …
nitrogen and oxygen to react.
When fossil fuels are burned in a confined space, the high temperatures can cause nitrogen and oxygen to react.
This leads to the formation of …
Toxic nitrogen oxides.
Incomplete combustion produces two problematic by-products:
- Carbon monoxide - a toxic gas.
- Particulates - small solid particles containing carbon and unburnt fuel.
Incomplete combustion happens when fuels are …
burned in insufficient oxygen
——— is an impurity that is present in all fossil fuels.
Sulfur
Sulfur is an impurity that is present in all fossil fuels.
Sulfur oxidises when burned. This produces the …
toxic gas sulfur dioxide.
What happens when fuels are burned in insufficient oxygen?
Incomplete combustion
Carbon monoxide binds to ———— in the blood.
haemoglobin
Carbon monoxide binds to haemoglobin in the blood.
This restricts the blood’s ability to transport ———- throughout the body.
oxygen
Carbon monoxide is …
odourless and colourless.
Carbon monoxide is odourless and colourless.
This means that …
it is difficult to detect in the air.
If exposed to too much carbon monoxide, symptoms can range from …
fainting to fatality.
Inhaling particulates can cause …
respiratory issues.
Particulates reflect incoming radiation out into …
space
Inhaling particulates can cause respiratory issues.
Particulates reflect incoming radiation out into space.
This leads to global dimming, which …
decreases the levels of sunlight available for photosynthesis. This can have knock-on effects for rainfall patterns.
Inhaling sulfur dioxide can cause …
respiratory issues.
Sulfur dioxide can react with water to form …
sulfuric acid.
Sulfuric acid is a major part of acid rain, which can cause:
- The corrosion of steel.
- The weathering of buildings, monuments and statues.
- The death of insects, plants, and aquatic organisms.
Inhaling nitrogen oxides can cause …
respiratory issues.
Nitrogen oxides can react with water to form …
nitric acid
Like sulfuric acid, nitric acid is a key component in …
acid rain.
Global dimming happens because ————- reflect incoming radiation into space.
particulates
Atmospheric pollutants from fossil fuels:
- nitrogen oxides
- carbon dioxide
- sulphur dioxide
- carbon monoxide
- particulates
What are atmospheric pollutants produced in the combustion engine of a car?
- nitrogen oxide
- carbon dioxide
Fossil fuels are formed from organic material that has been …
buried and compressed.
When fossil fuels are burned, a ——- reaction occurs
combustion
When fossil fuels are burned, a combustion reaction occurs. In this reaction, the organic molecules formed by —————- react with oxygen.
photosynthesis
When fossil fuels are burned, a combustion reaction occurs. In this reaction, the organic molecules formed by photosynthesis react with…
oxygen.
When fossil fuels are burned, a combustion reaction occurs. In this reaction, the organic molecules formed by photosynthesis react with oxygen. One of the products of this reaction is …
carbon dioxide.
Greenhouse gases allow 1. wavelength radiation from the sun to pass through Earth’s atmosphere but they absorb ——- wavelength radiation which bounces back.
- short
- long
What was the main gas produced by the frequent eruptions of these volcanoes?
Carbon dioxide