Which noble gas has the lowest boiling point?

Explain the variations in the following properties of group $18$ elements:
$(i)$ Atomic radii
$(ii)$ Ionisation enthalpy
$(iii)$ Electron gain enthalpy

Which of the following pairs of inert gases is used in flash bulbs?

Which one of the following does not exist?
$(i)$ $XeOF_{4}$
$(ii)$ $NeF_{2}$
$(iii)$ $XeF_{2}$
$(iv)$ $XeF_{6}$

Which of the following noble gases has the lowest polarizability?

Liquid $X$ is used in a bubble chamber to detect neutral mesons and gamma photons. Then, $X$ is