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Edexcel IGCSE Chemistry · Spec 2.14

Percentage of Oxygen in Air

The experiment used to find the percentage of oxygen in air.

Chemistry revision video

Percentage of Oxygen in Air

Spec 2.14

What you need to know

  • Describe an experiment to find the percentage of oxygen in air
  • Explain the results
  • Calculate the percentage of oxygen

Active recall

Quick check

Answer each question before opening the answer.

How can you show that air is about 20% oxygen?

Pass a fixed volume of air over heated copper (or burn something) so the oxygen is used up, and measure the decrease in volume.

What result would you expect?

The volume of air decreases by about one fifth (20%).

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