Write electron configuration, bond order and Magnetic property of Hydrogen $\left( {{{\rm{H}}_2}} \right)$ molecule.

Electron configuration : It is formed by the combination of two hydrogen atoms ( $1 s$ ). Total number of electron in $\mathrm{H}_{2}$ molecule $=2$

In $\mathrm{H}_{2}$ molecule $\mathrm{BMO}: \sigma_{1 s}$ and $\sigma_{1 s}^{*}$

$\therefore \mathrm{e}^{-}$configuration of $\mathrm{H}_{2}$ molecule : $\left(\sigma_{1 s}\right)^{2}\left(\sigma_{1 s}^{*}\right)^{0}$

Bond order : BMO : $\sigma(1 s)=2$ electron and ABMO : $\left(\sigma_{1 s}^{*}\right)=0$ electron

$\therefore$ Bond order $=\frac{\mathrm{N}_{\mathrm{b}}-\mathrm{N}_{\mathrm{a}}}{2}=\frac{(2-0)}{2}=1$

This means two $\mathrm{H}$ atoms are bonded together by a single covalent bond.

Magnetic property : In $\mathrm{H}_{2}$ molecule, no unpaired electron is present and only electron paired present. $\therefore \mathrm{H}_{2}$ molecule is diamagnetic.