Proportions of Gases in the Atmosphere
Chemistry: AQA GCSE Higher, topic 9.1.1
Importance of Atmospheric Gases
The Earth's atmosphere contains numerous gases, each of which has an effect on the success of our planet's organisms.
Nitrogen
- Nitrogen is a key component of proteins, which are essential for growth.
- Whilst it is abundant in the atmosphere, the producers found at the base of food chains are not able to exploit this source. Instead, they must absorb nitrogen in the form of soluble nitrates from the soil.
Oxygen
- Oxygen is a reactant in respiration - a chemical reaction that takes place in all living cells.
- As humans, we breathe oxygen into our lungs. From here, it diffuses into our blood and is carried to all the cells in our body.
Carbon dioxide and water vapour
- Carbon dioxide and water vapour are greenhouse gases.
- Greenhouse gases absorb and then re-radiate heat energy that is reflected off the Earth's surface. This is known as the greenhouse effect.
- If the greenhouse effect is too strong, it can lead to global warming.
Test yourself on Proportions of Gases in the Atmosphere
Name the 2 gases with the largest proportions in the atmosphere
Approximately what percentage of the Earth's atmosphere is made up of nitrogen? (Round to the nearest 10%.)
Which chemical reaction, occurring in all living cells, uses oxygen as a reactant?
Oxygen diffuses from the lungs into the blood and is carried to all the cells in the body. Why do all the cells in the body need a supply of oxygen?
Carbon dioxide and water vapour are greenhouse gases that absorb and re-radiate heat energy reflected off the Earth's surface. Why would an increase in atmospheric carbon dioxide be likely to strengthen the greenhouse effect?