Question

The pairs of species of oxygen and their magnetic behaviours are not noted below . Which of the following presents the correct description ?

• A. $O^{+},O_2^{2-}$ - Both paramagnetic
• B. $O_2^{+},O_2$ - Both paramagnetic
• C. $O_2^{-},O_2^{2-}$ - Both Diamagnetic
• D. $O,O_2^{2-}$ - Both paramagnetic

Answer 1

Answer: (B)

$O_2^{+},O_2$ - Both paramagnetic

$O_2$ is paramagnetic because it contains $2$ unpaired electrons in antibonding molecular orbitals. In, $O_2^{+}$, one electron is removed from antibonding molecular orbitals. But one electron is present. This causes paramagnetic in $O_2^{+}$. Hence, both $O_2^{+}$ and $O_2$ are paramagnetic .