we find the number of moles with the formula
pV=nRT
27C=300k
3.2*30=n*0.082*300
n=96/24.6=3.9 moles
we have the mass ant the number of moles so we can calculate the molar mass
283.3/3.9=72.64g/moles
that means X's mass is 72.64/2=36.3 so the element is Kr(Kriptonium)