Exam 9: The Chemical Bond

What is the separation between the highest occupied and lowest unoccupied molecular orbitals of benzene?

Hückel theory predicts that the energies of the  orbitals of 1,3-butadiene, C₄H₆, are E₁=α+1.62α E₂=α+1.62α E₃=α-1.62α E₄=α-1.62α Predict the wavelength of the lowest energy transition in the electronic spectrum of butadiene, given that  = -3.8 eV.

Which of the following describes the electronic configuration of the electronic ground state of the F₂ molecule?

Use molecular orbital theory to determine whether the Ne₂⁺ ion is likely to be bound, and if so, to predict its bond order.

What is the symmetry of the bonding molecular orbital formed by a linear combination of the p_x or p_y atomic orbitals in a homonuclear diatomic molecule?

Which of the following represents the best description of the bonding in an octahedral molecule such as sulfur hexafluoride, SF₆, using valence-bond theory.

Using the Hückel method, the energies of the  orbitals of the allyl radical, C₃H₄, are calculated to be ,α and α±√2 β Calculate the energy of the delocalised  system relative to the energy of electrons in isolated p orbitals.

Which of the following spin functions represents a valid spin wavefunction for two paired electrons?

How many molecular orbitals can be built from the valence atomic orbitals of molecular bromine, Br₂?

The bonding within xenon tetrafluoride, XeF₄, is best described, using valence-bond and valence-shell electron-pair repulsion theory, as resulting from formation of sp³d² hybrid orbitals on the xenon atom, four of which form  bonds to fluorine atoms. Which of the following structures is consistent with this model?