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Chemistry · Paper 2 · Foundation + Higher · C9

Air today and the early atmosphere

Key ideas1 of 3

What is in the air?

Dry air is about 78% nitrogen, 21% oxygen and 1% other gases, mainly argon. Remember roughly four-fifths nitrogen and one-fifth oxygen. Water vapour varies and is not included in dry-air percentages.

Dry-air bar chart: largest section 78%, second section 21%, remaining section 1%. Nitrogen 78%, oxygen 21%, other gases 1%.

Next: Oxygen increased; carbon dioxide decreased →
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Daily 5 · Exam practice · Revision sheet ↓

Foundation + Higher · C9. All C9 lessons are shared by Foundation and Higher Tier.

AQA Combined Science Trilogy 8464 · 5.9.1.1–5.9.1.2. Original notes, questions and diagrams. Models are simplified; illustrative data are labelled.