Composition of dry air (1 mark)

GCSE · Combined Science · OCR · C6.3 — Interpreting and interacting with Earth systems: the atmosphere — its composition and evolution; greenhouse gases and pollutants

Question

Question: Which gas makes up approximately 78% of the Earth's modern atmosphere?

A) Oxygen
B) Carbon dioxide
C) Nitrogen
D) Argon

Mark scheme (1 mark):

C — Nitrogen (1).
No mark for any other answer; common error: selecting oxygen (21%).

1 mark · take your time before peeking.

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Generated by TopMyGrade AI · cross-check official sources before relying on the mark-scheme phrasing.