The number of species from the following which are paramagnetic and with bond order equal to one is___________

$\mathrm{H}_2, \mathrm{He}_2^{+}, \mathrm{O}_2^{+}, \mathrm{N}_2^{2-}, \mathrm{O}_2^{2-}, \mathrm{F}_2, \mathrm{Ne}_2^{+}, \mathrm{B}_2$

"Isoelectronic molecules and ions have identical bond orders." Explain by examples.

The correct order of the $O-O$ bond length in $O_2$ , $H_2O_2$ and $O_3$ is

Select the $CORRECT$ statement if internuclear axis is $y-$ axis

Bond energies in $NO,\,N{O^ + }$ and $N{O^ – }$ are such as