issb general knowledge MCQ #5

Which gas is most abundant in Earth's atmosphere?

issb general knowledge MCQ #5

  1. Question 1

    Q1. Which gas is most abundant in Earth's atmosphere?

    • A) Oxygen
    • B) Carbon dioxide
    • C) Nitrogen
    • D) Hydrogen

    Answer: Nitrogen

    Explanation: Nitrogen ≈ 78%, Oxygen ≈ 21%. Students often wrongly pick oxygen because we breathe it — nitrogen dominates by volume.