a
\(\sigma 1 \mathrm{s}^{2}, \sigma^{*} 1 \mathrm{s}^{2}, \sigma 2 \mathrm{s}^{2}, \sigma^{*} 2 \mathrm{s}^{2}, \sigma 2 \mathrm{p}_{2}^{2}, \pi 2 \mathrm{p}_{\mathrm{x}}^{2} \approx \pi 2 \mathrm{p}_{\mathrm{x}}^{2}, \pi^{*} 2 \mathrm{p}_{\mathrm{x}}^{2} \approx \mathrm{\pi}^{*} 2 \mathrm{p}_{\mathrm{y}}^{2}\)

Bond order \(=\frac{N_{b}-N_{a}}{2}\) (where \(N_{b}=\) number of electrons in bonding molecular orbital

\(\mathrm{N}_{\mathrm{a}}=\) number of electrons in anti \(-\) bonding molecular orbital)

\(O_{2}^{2-}(8+8+2=18)\)

\(\mathrm{BO}=\frac{\mathrm{N}_{\mathrm{b}}-\mathrm{N}_{\mathrm{a}}}{2}=\frac{10-8}{2}=1\)

\(\mathrm{B}_{2}(5+5=10)=\sigma 1 \mathrm{s}^{2}, \sigma^{*} 1 \mathrm{s}^{2}, \sigma 2 \mathrm{s}^{2}, \sigma^{*} 2 \mathrm{s}^{2}, \pi 2 \mathrm{p}_{\mathrm{x}}^{1} \approx \pi 2 \mathrm{p}_{\mathrm{y}}^{1}\)

\(B O=\frac{6-4}{2}\)

similarly, order of;

\(O_{2}^{+}=2.5, \mathrm{NO}^{+}=3\)

\(\mathrm{NO}=2.5, \mathrm{CO}=3\)

\(\mathrm{N}_{2}=3\) and \(\mathrm{O}_{2}=2\)

\(\sigma 1 \mathrm{s}^{2}, \sigma^{*} 1 \mathrm{s}^{2}, \sigma 2 \mathrm{s}^{2}, \sigma^{*} 2 \mathrm{s}^{2}, \sigma 2 \mathrm{p}_{2}^{2}, \pi 2 \mathrm{p}_{\mathrm{x}}^{2} \approx \pi 2 \mathrm{p}_{\mathrm{y}}^{2}, \pi^{*} 2 \mathrm{p}_{\mathrm{x}}^{2} \approx \pi^{*} 2 \mathrm{p}_{\mathrm{y}}^{2}\)

Bond order \(=\frac{N_{\mathrm{b}}-\mathrm{N}_{a}}{2}\)

(where \(N_{b}=\) number of electrons in bonding molecular orbital

\(\mathrm{N}_{a}=\) number of electrons in anti - bonding molecular orbital \(O_{2}^{2-}(8+8+2=18)\)

\(\mathrm{BO}=\frac{\mathrm{N}_{\mathrm{b}}-\mathrm{N}_{\mathrm{a}}}{2}=\frac{10-\mathrm{g}}{2}=1\)

\(\mathrm{B}_{2}(5+5=10)=\sigma 1 \mathrm{s}^{2}, \sigma^{*} 1 \mathrm{s}^{2}, \sigma 2 \mathrm{s}^{2}, \sigma^{*} 2 \mathrm{s}^{2}, \pi 2 \mathrm{p}_{\mathrm{x}}^{1} \approx \pi 2 \mathrm{p}_{\mathrm{y}}^{1}\)

\(B O=\frac{6-4}{2}\)

similarty, order of:

\(O_{2}^{+}=2.5, \mathrm{NO}^{+}=3\)

\(\mathrm{NO}=2.5, \mathrm{CO}=3\)

\(\mathrm{N}_{2}=3\) and \(\mathrm{O}_{2}=2\)