Question

answer the following: *
the orbital diagram for a ground state oxygen atom is
a. 1s: ↑↓, 2s: ↑↓, 2p: ↑, ↑, ↑
b. 1s: ↑↓, 2s: ↑↓, 2p: ↑↓, ↑↓, _
c. 1s: ↑↓, 2s: ↑↓, 2p: ↑↓, ↑, _
d. 1s: ↑↓, 2s: ↑↓, 2p: ↑↓, ↑, ↑
e. 1s: ↑↓, 2s: ↑↓, 2p: ↑↓, ↑↓, ↑
○ a
○ b
○ c
○ d
○ e

Explanation:

• Oxygen has an atomic number of 8. So, its electron configuration is \(1s^{2}2s^{2}2p^{4}\).
• According to Hund's rule, electrons in the same sub - shell (here \(2p\) sub - shell) first occupy degenerate orbitals singly with parallel spins before pairing up.
• In the \(2p\) sub - shell (which has 3 degenerate orbitals), for \(2p^{4}\) configuration, two orbitals will have paired electrons (\(\uparrow\downarrow\)) and one orbital will have two unpaired electrons (\(\uparrow\)).
• The \(1s\) and \(2s\) orbitals are completely filled (\(\uparrow\downarrow\) in each).

Answer:

D.