Chemistry - C9 Notes

The Evolution of the Atmosphere

• During the first billion years of Earth's history, scientists think that the atmosphere was made from gases from volcanoes
• Five gases from the early atmosphere are carbon dioxide, nitrogen, water vapour, methane and ammonia
• Levels of carbon dioxide were reduced by plants and algae carrying out photosynthesis
• Today, the atmosphere is made of 80% nitrogen, 20% oxygen, carbon dioxide, noble gases and water vapour

Pollution and Climate Change

• Three greenhouse gases are carbon dioxide, methane, and water vapour
• The greenhouse effect works…