Write the increasing order of energy for $2p, 3p, 4p, 5p$ orbitals.

The maximum number of permissible rotational orientations of the $2s$ electron of lithium atom in ground state is

What is an atomic orbital?

An ion with a charge of $-2$ has the electronic configuration $1s^2, 2s^2, 2p^6$. Identify the ion.

If the number of radial nodes in an $s$-orbital is $(n - 1)$,and the question asks for the orbital where the number of nodes is $(n - 1)$,which orbital corresponds to the given expression $(n - 1)$?

Explain the Aufbau principle with an example.