Hydrolysis of $XeF_4$ gives $HF$,$O_2$,$Xe$ and '$X$'. The structure of '$X$' is

Xenon reacts best with which of the following?

Assertion $(A)$: The boiling points of noble gases increase from $He$ to $Xe$.
Reason $(R)$: The interatomic van der Waals' attractive forces increase from $He$ to $Xe$.
The correct answer is:

What are the elements at the end of periods $1$ to $7$ called? Which are these elements?

Which one of the following noble gases is the least polarizable?

Why has it been difficult to study the chemistry of radon?