Question

The paramagnetism of $O_2^{+}$ is due to the presence of an odd electron in the MO

• A. ${\sigma }^{\ast }2s$
• B. $\pi 2p_y$
• C. ${\pi }^{\ast }2p_x$
• D. ${\sigma }^{\ast }2p_x$
• E. $\pi 2p_x$

Answer 1

Answer: (B)

The electronic configuration of oxygen molecule ion is as
$O_2^{+}:KK\sigma 2s^2,{\sigma }^{\ast }2s^2,\sigma 2p_z^2,\pi 2p_x^2\approx \pi 2p_y^2,{\pi }^{\ast }2p_x^1$
Due to the presence of an odd electron in the ${\pi }^{\ast }2p_x$ molecular orbital, $O_2^{+}$ is paramagnetic.