Question

which of the following is the correct orbital diagram for oxygen?

Explanation:

Oxygen has 8 electrons. The electron - configuration is $1s^{2}2s^{2}2p^{4}$. According to Hund's rule, electrons in the 2p sub - shell first occupy each of the three 2p orbitals singly with parallel spins before pairing up. The 1s and 2s orbitals are filled with 2 electrons each (paired with opposite spins).

Answer:

a