Among the following species, the diamagnetic molecule is

Number of paramagnetic oxides among the following given oxides is ..... .

$\mathrm{Li}_{2} \mathrm{O}, \mathrm{CaO}, \mathrm{Na}_{2} \mathrm{O}_{2}, \mathrm{KO}_{2}, \mathrm{MgO}$ and $\mathrm{K}_{2} \mathrm{O}$

Which of the following $M.O$ has two nodal Plane's

During change of $O_2$ to $O_2^-$ ion, the electron adds on which one of the following orbitals?

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

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

Number of lone pair (s) of electrons on central atom and the shape of $BrF _{3}$ molecule respectively, are ..... .