1. Noble gases being monoatomic have no interatomic forces except weak dispersion forces and therefore, they are liquefied at very low temperatures. Hence, they have low boiling points.
2. XeF2 and XeF2 are formed by the direct reaction of elements under the specific conditions.
They are readly hydrolysed even by traces of water,
e.g. 2XeF2(s) + 2H2O(l) → 2Xe(g) + 4HF(aq) + O2(g)