Which of the following species contain only $\pi \,-\,$ bond but exhibit paramagnetic nature ?
$C_2$
$B_2$
${O_2}^{-1}$
$N_2$
During change of $O^2$ to $O_2^-$ ion, the electron adds on which one of the following orbitals?
$\sigma _{2s}^*$ orbital is similar to ....... orbital
The correct order of bond dissociation energy among $N_2, O_2, O_2^-$ is shown in which of the following arrangements?
The bond order of $O_2^ + $ is the same as in
Which of the following has unpaired electron $(s)$ ?