Combined Science GCSE
Changes in atmospheric composition over geological time
What Changes in atmospheric composition over geological time means in Combined Science GCSE, as defined for AQA.
Definition of Changes in atmospheric composition over geological time
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Reference: AQA
Earth's atmosphere changed from an early mixture of carbon dioxide, water vapour, methane and ammonia to today's atmosphere of 78% nitrogen and 21% oxygen.
Topics that use Changes in atmospheric composition over geological time
- How carbon dioxide decreased (AQA GCSE)
Related terms
- Atmospheric evolution
- Biomass and carbon storage
- Carbon stores
- Causes of carbon dioxide decrease
- Causes of oxygen and nitrogen increase
- Coal
- Crude oil and natural gas
- Hydrocarbons
Using Changes in atmospheric composition over geological time in the exam
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