The sum of bond order of $O_2^{+}$,$O_2^{-}$,$O_2$ and $O_2^{2+}$ is equal to

Arrange the molecules $B_2, He_2, N_2$ and $C_2$ in the increasing order of their bond order values.

The common features among the species $CN^{-}$,$CO$ and $NO^{+}$ are

Which of the following combinations leads to the $HOMO$ of the $N_2$ molecule?

In a homonuclear diatomic molecule,which of the following sets of orbitals is degenerate?

Consider the following statements.
$I$. In the conversion of $O_2$ to $O_2^{2+}$,bond order decreases.
$II$. In the conversion of $O_2$ to $O_2^{2+}$,magnetic property is not changed.
$III$. In the conversion of $O_2$ to $O_2^{2+}$,bond length decreases.
$IV$. $O_2^{2-}$ and $B_2$ have same bond order.
Identify the correct statements.