Question

Observe the following molecules / ions
$H_2,N_2,O_2,N_2^{+},O_2^{+},O_2^{-},F_2.$ Identify correct
statement.

• A. $H_2,N_2,O_2,F_2$ show diamagnetic property
• B. $O_2,O_2^{+},O_2^{-},N_2^{+}$ show paramagnetic property
• C. $N_2,F_2,O_2^{+},O_2^{-}$ show diamagnetic property
• D. $H_2,N_2^{+},O_2^{+},O_2^{-}$ show paramagnetic property

Answer 1

Answer: (B)

$H_2-(\sigma ls{)}^2$

$H_2$ does not have any unpaired electron hence diamagnetic in nature.

$N_2\to KK(\sigma 2s{)}^2{\left({\sigma }^{\ast }2s\right)}^2{\left(\pi 2p_x\right)}^2{\left(\pi 2p_y\right)}^2{\left(\sigma p_z\right)}^2$

$N_2$ does not have any unpaired electron hence diamagnetic in nature.

$O_2\to K{K}^1(\sigma 2s{)}^2{\left({\sigma }^{\star }2s\right)}^2{\left(\sigma 2p_z\right)}^2{\left(\pi 2p_x\right)}^2{\left(\pi 2p_y\right)}^2$

${\left({\pi }^{\ast }2p_x\right)}^1{\left({\pi }^{\star }2p_y\right)}^1$

$O_2$ have two unpaired electrons hence

paramagnetic in nature.

$N_2^{+}\to K{K}^1(\sigma 2s{)}^2{\left({\sigma }^{\ast }2s\right)}^2{\left(\pi 2p_x\right)}^2{\left(\pi 2p_y\right)}^2{\left(\pi 2p_z\right)}^1$

$N_2$ have one unpaired electron, so it paramagnetic in nature.

$O_2^{+}\to K{K}^{\prime }(\sigma 2s{)}^2{\left({\sigma }^{\ast }2s\right)}^2{\left(\sigma 2p_z\right)}^2{\left(\pi 2p_x\right)}^2{\left(\pi 2p_y\right)}^2$

${\left({\pi }_2^{\ast }{p}_x\right)}^1{\left({\pi }^{\ast }2p_y\right)}^0$

$O_2^{+}$ has unpaired electron, so it is paramagnetic in nature.

$O_2^{-}\to K{K}^{\prime }(\sigma 2s{)}^2{\left({\sigma }^{\ast }2s\right)}^2{\left(\sigma 2p_z\right)}^2{\left(\pi 2p_x\right)}^2{\left(\pi 2p_y\right)}^2$

${\left({\pi }^{\ast }2p_x\right)}^2{\left({\pi }^{\ast }2p_y\right)}^1$

$F_2\to K{K}^{\prime }(\sigma 2s{)}^2{\left({\sigma }^{\ast }2s\right)}^2{\left(\sigma 2p_z\right)}^2{\left(\pi 2p_x\right)}^2{\left(\pi 2p_y\right)}^2$

${\left({\pi }^{\ast }2p_x\right)}^2{\left({\pi }^{\ast }2p_y\right)}^2$

$F_2$ does not have unpaired electron, hence diamagnetic in nature. Hence, the molecules, $N_2^{+},O_2,O_2^{+},O_2^{-}$ and $H_2,N_2,F_2$

are paramagnetic and diamagnetic respectively due to presence of unpaired and paired electrons.