The calculated bond order of superoxide ion $(O_{2}^{-})$ is

The wave functions of $1s$-orbitals of two hydrogen atoms are $\psi_A$ and $\psi_B$. $\psi_A$ and $\psi_B$ are linearly combined to form two molecular orbitals ($\sigma$ and $\sigma^*$). Which of the following statements are correct?
$I$. $\sigma^*$ is equal to $(\psi_A - \psi_B)$.
$II$. In $\sigma$-orbital,one nodal plane is present in between two nuclei.
$III$. The energy of $\sigma$-orbital is lower than the energy of $\sigma^*$-orbital.

Which of the following diatomic molecular species has only $\pi$ bonds according to Molecular Orbital Theory?

The linear combination of atomic orbitals to form molecular orbitals takes place only when the combining atomic orbitals:
$A$. have the same energy
$B$. have the minimum overlap
$C$. have same symmetry about the molecular axis
$D$. have different symmetry about the molecular axis
Choose the most appropriate from the options given below:

Find the odd-electron molecules from the following:
$(i) C_2, (ii) H_2, (iii) SCl_2, (iv) NO, (v) NO_2$

In which of the following molecules do the $\pi 2p_x$ and $\pi 2p_y$ orbitals fill after the $\sigma 2p_z$ molecular orbital?