Question

The pairs of species of oxygen and their magnetic behaviours are noted below. Which of the following presents the correct description ?

• A. $O , O^{2-}_2$ - Both paramagnetic
• B. $O^-_2 , O^{2-}_2$ - Both diamagnetic
• C. $O^+ , O^{2-}_2$ - Both paramagnetic
• D. $O^+_2 , O_2$ - Both paramagnetic

Answer 1

Answer: (D)

$ O_2^+ = KK \sigma 2 s^2 \, \, \sigma^{\ast} 2s^2 \, \, \sigma 2 p_z^2 (\pi 2 p_x^2 = \pi 2 p_y^2) (\pi^{\ast} 2 p_x^1)$
$ O_2 = KK \sigma 2 s^2 \, \, \sigma^{\ast} 2s^2 \, \, \sigma 2 p_z^2 (\pi 2 p_x^2 = \pi 2 p_y^2) (\pi^{\ast} 2 p_x^1 = \pi^{\ast} 2 p_y^1)$
$O_2$ and $O_2^+$ contain unpaired electron in $\pi^{\ast} $ ABMO so paramagnetic.