Question
Assuming Z-axis as molecular (or internuclear) axis, label the molecular orbtials formed by the following combinations of atomic orbitals: (i) 1 s + 1 s (ii) 2py – 2pv (iii) 2Pz – 2pz.
Solution
(i) Combination of 1s and 1s atomic orbitals gives rise two molecular orbital such as bonding and antibonding : 
(ii) Combination of 2py and 2py atomic orbitals gives rise to give two molecular orbitals, such as bonding and antibonding: 
(iii) The combination of 2pz and 2pz atomic orbitals gives rise to give two molecular orbitals such as bonding and antibonding molecular orbital.
