Home PYQs UPPSC UPPSC MCQs Prelims 2005 (GS Paper I)

Question

Which one of the following Noble Gases is not present in air?

  1. Helium
  2. Argon
  3. Radon
  4. Neon

Answer:

Option C: Radon

Detailed Solution:

The correct answer is “Radon”.

Radon is the noble gas that is not present in the Earth's atmosphere. Radon is radioactive and is produced by the decay of radium-226, which is found in uranium ores.