The number of radial nodes present in $3p$ orbital is

The electronic configurations of four elements are given in brackets:
$L(1s^2, 2s^2\ 2p^1);$ $M(1s^2, 2s^2\ 2p^5)$
$Q(1s^2, 2s^2\ 2p^6, 3s^1);$ $R(1s^2, 2s^2\ 2p^2)$
The element that would most readily form a diatomic molecule is:

What is the difference between the $2s$ orbital of hydrogen and the $2s$ orbital of other multi-electron atoms?

What is the maximum number of electrons that can be accommodated in a shell with principal quantum number $n = 4$?

What is the number of electrons in a $Na$ atom for which $l + m = 0$?

Write the values of $n, l, m_{l}, m_{s}$ for $4f$.