GCSE Chemistry, 4.9- Atmosphere

State 5 gases that is produced from volcanoes.

[5 marks]

Carbon dioxide, water vapour, nitrogen, methane and ammonia.

There are increase in oxygen level and decrease in carbon dioxide from Earth’s early atmosphere to Earth’s atmosphere in 2021

Explain the process of the change of Earth’s atmosphere. [6 marks]

• Volcanic activity release carbon dioxide and water vapour.

• Water vapour condensed to form ocean.

• Some carbon dioxide dissolved in oceans which cause carbonate to produce sediment.

• Carbon locked up in sedimentary rock.

• Algae evolved.

• Algae release oxygen and absorb carbon dioxide by photosynthesis.

Describe the process the formation of coal.

[4 marks]

• Remains of tree cannot decompose in wetland.

• Does not meet the condition for in order to decompose by bacteria.

• Cover with sediment and compressed.

• High temperature and high pressure create coal.

Describe the process the formation of crude oil.

[4 marks]

• Remains of plankton cannot decompose in sea bed.

• Does not meet the condition for in order to decompose by bacteria.

• Cover with sediment and compressed.

• High temperature and high pressure convert them into crude oil.

Explain the greenhouse effect. [4 marks]

• Most short wavelength radiation absorbed by surface of the earth.

• Some short wavelength reflected back due to not interact strongly with gas molecule.

• Earth radiates long wavelength radiation which some of them interact with greenhouses gas.

• Energy trapped and increase temperature.