C9: Chemistry of the Atmosphere

How was the early atmosphere formed
Surface of Earth covered in volcanoes that erupted and released lots of gases
Early atmosphere was probably mostly _________________- with virtually no oxygen. Quite like atmosphere of Mars and Venus today.
Carbon dioxide
Volcanic activity also released ___________, which built up in the atmosphere over time, as well as ______________________ and and small amount of ________ and __________
Water vapor
When the water vapor in the atmosphere condensed it formed the________-
Lots of carbon dioxide was removed from the early atmosphere as it dissolved in ____________. The dissolved carbon dioxide then went through a series of reactions to form _________ that formed sediments on the seabed
the ocean
Carbonate precipitates
Green plants and algae evolved and absorbed some of the CO2 so that they could carry out ______________
Later marine animals evolved. Their shells and skeletons contained _________ from the ocean.
Some of the carbon these organisms took in from the atmosphere and oceans became locked up in ___________ after the organisms died
Rocks and fossil fuels
How do plants, plankton, and marine animals keep carbon dioxide levels in atmosphere reduced?
When they die, they fall to the seabed and get buried by layers of sediment. Over millions of years, they become compressed and form sedimentary rocks, oil and gas - trapping the carbon within them.
Things like coal, crude oil, and natural gas are called
Fossil fuels
Crude oil and natural gas are formed from deposits of _________. These fossil fuels form reservoirs under the seabed when they get trapped in rocks.
Coal is a sedimentary rock made from thick ___________
Plant deposits
Limestone is also a sedimentary rock, mostly made of...
Calcium carbonate deposits from the shells and skeletons of marine organisms
Green plants and algae produce oxygen by ....
How could more complex life (like animals evolve)
Oxygen levels built up in the atmosphere over time
200 million years ago atmosphere reached a composition similar today being
80% nitrogen 0% oxygen and small amounts of other gases being less than 1% of the atmosphere (mainly CO2, noble gases, and water vapor)
______ evolved first about 2.7 billion years ago. Then over the next billion years or so, green plants also evolved.
Greenhouse gases don't absorb the incoming short wavelength radiation form the sun, but they do absorb the long wavelength radiation that gets reflected back off the Earth. They then re radiate it in all directions including back towards the Earth. The long wave radiation is thermal radiation so it results in....
Warming of the surface of the Earth. This is the greenhouse effect.
Human activity that effects amount of greenhouse gases in atmosphere
Burning fossil fuels
Creating waste
Increasing carbon dioxide is linked to...
Climate Change
An increase in global temperature could lead to ....
Polar ice caps melting causing a rise in sea levels, increased flooding in coastal areas and coastal erosion
Changes in rainfall patterns may cause...
Some regions to get too much or too little water. This along with changes in temperature may affect the ability of certain regions to produce food. Frequency and severity of storms may also increase.
Changes in temperature and the amount of water available in a habitat may affect wild species, leading to differences in their ________________
Carbon footprints
Measure of amount of CO2 and other greenhouse gases released over full life cycle of something (can be anything e.g. school bus, olympics, toastie maker)
Measuring carbon footprint of something can be...
really hard (or even impossible)
Anything that reduces the amount of greenhouse gases given out by a process will also reduce its...
Carbon footprint
Ways of reducing carbon footprints
Using renewable energy sources/nuclear energy over fossil fuels
More efficient processes
Gov. could tax companies/individuals based on amt of greenhouse gases they emit
Gov. can put cap on emissions of all greenhouse gases that companies make, then sell licences for emissions up to that cap
Technology that captures CO2 before released into atmospheres and stores deep underground in cracks in the rock such as oil wells
Why are goverments worried about making changes for environment
Making these changes will impact on the economic growth of communities which could be bad for people's well being. Important for countries still developing.
Incomplete combustion
If there's not enough oxygen, some of the fuel doesn't burn
SOlid particles of soot (carbon) and unburnt fuel are released and Carbon Monoxide can be produced as well as CO2
If particles are inhaled...
Can get stuck in lungs and cause damage. This can lead to respiratory problems.
Why are particles bad for environment
They, or the clouds they help produce, reflect sunlight back into space. This means less light reaches the Earth- causing global dimming
Why is carbon monoxide so harmful
By binding to hemoglobin in your body that normally carries O2, less oxygen is transported round your body. A lack of oxygen can lead to fainting, a coma, or even death. Carbon monoxide is very hard to detect as it has no color or smell.
_______________ is released during combustion
Sulfur dioxide
What are nitrogen oxides created from?
A reaction between the nitrogen and oxygen in the air, caused by the heat heat of the burning.
What happens when nitrogen oxides mix with clouds
They form dilute sulfuric acid or dilute nitric acid (this falls as acid rain)
What does acid rain do?
Kills plants and damages buildings and statues. It also makes metal corrode.
What does sulfur dioxide and nitrogen oxide cause in humans?
Respiratory problems