Complete the following questions in the space below True or

Complete the following questions in the space below. True or False? The true dipole moment is always greater than the calculated dipole moment for a chemical bond. The Born-Oppenheimer approximation is generally valid because nuclei move much faster than electrons due to their higher mass. Molecular orbital theory is superior to valence bond theory in explaining the behaviour of molecules in the excited state. sigma bonding molecular orbitals are symmetric around the bond axis. All three pi anti bonding molecular orbitals are degenerate. Explain the principles underlying the construction of trial wave functions in the molecular orbital method. in the valence bond method.

Solution

1 a) FALSE the calculated dipole moments are always higher than true dipole moment . the average deviation is 32 % of the experimented value

b)FALSE nuclei have very less velocity as compared to electron due to their large mass

c)TRUE unlike the valence bond theory the molecular orbital theory takes into consideration the overlap and energies of bonding and antibonding electrons residing in particular molecular orbital.