Question

Suggest 2 reasons why the noble gases become less ideal in their behaviour down the group from helium to xenon.

Answer 1

Reason1: electrons on farther layers become free easyer
2nd reason: volume of atoms grows (from Helium to Xeon) so instead  of boyle-mariot law equation (PV=vRT) is  more accurate to use van der walls equations that adds to the boyle-mariot equation the volume occupied by the atoms of the gas to the volume of the space between the atoms P(Vm-b)=vRT