Question

Which of the following statements about the MO theory of chemical bonding is not true.And How is the stability of a molecule affected by removing an electron from a bonding orbital?

		MOs froms from two atomic orbitals always occur as bonding and antibonding pairs.
		MOs are localised between pairs of atoms.
		MOs are most effective when the energies of the atomic orbitals are similar.
		MOs are most effective when the spatial overlap of atomic orbitals is large.

Answer 1

True: MOs froms from two atomic orbitals always occur as bonding and antibonding pairs.

False: MOs are localised between pairs of atoms. Because in polyatomic molecules in different resonating structures MO can delocalise.

True: MOs are most effective when the energies of the atomic orbitals are similar.

True: MOs are most effective when the spatial overlap of atomic orbitals is large.

Answer: B

If an electron is removed from a bonding Orbital, number of bonding electrons decreases which result in the decrease in Bond Order. Hence stabilty decreases.