9.9 The existence of compounds of the noble gases was once a great surprise and stimulated a great deal of theoret- ical work. Sketch the molecular orbital energy level diagram for XeF and deduce its ground-state electron configurations. Is XeF likely to have a shorter or longer bond than XeF*?

“Inert” xenon actually forms several compounds, especially with the highly electronegative elements oxygen and fluorine.The simple fluorides XeF₂, XeF₄, and XeF₆ are all formed by di-rect reaction of the elements. As you might expect from the sizeof the xenon atom, the Xe-F bond is not a strong one. Calcu-late the Xe-F bond energy in XeF₆, given that the heat of for-mation is 402 kJ/mol.

Carbon monoxide, CO, is isoelectronic to N2. (a) Draw aLewis structure for CO that satisfies the octet rule. (b) Assumethat the diagram in Figure 9.46 can be used to describethe MOs of CO. What is the predicted bond order forCO? Is this answer in accord with the Lewis structure youdrew in part (a)? (c) Experimentally, it is found that thehighest energy electrons in CO reside in a σ-type MO. Isthat observation consistent with Figure 9.46? If not, whatmodification needs to be made to the diagram? How doesthis modification relate to Figure 9.43? (d) Would you expectthe π2p MOs of CO to have equal atomic orbital contributionsfrom the C and O atoms? If not, which atom wouldhave the greater contribution?

Use MO theory to explain the following: O2P * 2p, 2pх 2ру TT 2p 2р, 2рx 2ру 2р, 2рх 2ру 2р, 2рх 2ру O 2P O 2P TT 2p O2s 02s 2s 2s 2s 2s O2s O2s i. The ionization energy of fluorine (F) is ~1700 kJ/mol, while the ionization energy of difluorine (F2) is ~1500 kJ/mol. + iii. The longest wavelength of light that can be absorbed by N2 is ~80 nm, while the longest wavelength of light that can be absorbed by F2 is ~100 nm. (No calculations are required for this). ii. Bez cannot exist, while both Be,* and Be,¯ can exist.