Learning objective
Describe how oxygen levels increased gradually as photosynthetic organisms became more widespread.
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At a glance
5
Flashcards
7
Questions
Topic
The composition and evolution of the Earth's atmosphere
Subtopic
How oxygen increased
Study support
Understand this objective
Short explanation
Describe how oxygen levels increased gradually as photosynthetic organisms became more widespread. This objective belongs to How oxygen increased within The composition and evolution of the Earth's atmosphere for AQA GCSE Chemistry 8462. A strong answer should use oxygen accurately, explain the chemistry behind the statement, and connect the idea back to the exact command in the objective. When revising, separate this point from neighbouring Chemistry ideas by naming the relevant particle, substance, process, calculation, observation, or structure before giving the final conclusion.
Key concepts
Why it matters
This objective helps connect How oxygen increased to exam-style questions, flashcards, and revision notes for The composition and evolution of the Earth's atmosphere.
Common mistakes
1 linked- Misunderstanding Oxygen Increase: Emphasize that oxygen levels increased gradually over time as photosynthetic organisms became more widespread.
Revision tools
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Flashcards5 linked cards
Flashcard 1 of 5
Practice Questions7 linked questions
Question 1 of 7
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Revision notestopic notes
Open the full topic revision notes when you are ready to review this objective in context.
Open revision notesRelated learning objectives
- Recall that the Earth's atmosphere is about 80 percent nitrogen.
The proportions of different gases in the atmosphere
- Recall that the Earth's atmosphere is about 20 percent oxygen.
The proportions of different gases in the atmosphere
- Recall that the Earth's atmosphere contains small proportions of other gases including carbon dioxide, water vapour and noble gases.
The proportions of different gases in the atmosphere
- Interpret simple data showing the proportions of gases in the atmosphere.
The proportions of different gases in the atmosphere
- Distinguish the major gases in the present atmosphere from trace atmospheric gases.
The proportions of different gases in the atmosphere