Question

What is the rarest gas on Earth?

Answer 1

Noble Gases:

• The elements Helium $\left(\mathrm{He}\right)$, Neon $\left(\mathrm{Ne}\right)$, Argon $\left(\mathrm{Ar}\right)$, Krypton $\left(\mathrm{Kr}\right)$, Xenon $\left(\mathrm{Xe}\right)$, and Radon $\left(\mathrm{Rn}\right)$ constitute the zero group $\left(18\right)$ of the periodic table.
• These are called noble gases because of their low chemical reactivity.
• These are also called rare gases or aerogens because they occur in the atmosphere in very small amounts. Their atmospheric abundance in dry air $~$$1\%$ by volume of which argon is the main constituent.

Hence, the noble gases are the rarest gases on Earth.