# Is radon a solid, liquid, or gas at room temperature?

The normal boiling point of radon is $- 61$ ""^@C, so it is barely a gas at $R T$.
While radon is an inert gas, it is an unstable nuclide with the half life of its common isotope, ""^222Rn, under 4 days.
As chemists, we are more interested in its boiling point/melting point etc. At $0$ ""^@C the gas has a density of just under $10 \cdot g \cdot {L}^{-} 1$, which is very dense indeed.