1. Certain atomic orbitals on two atoms were combined to form the following MOs. Name the atomic orbitals used and the MOs formed, and which MO has higher energy: and 2. How many electrons does it take to fill each of the following? (a) A sigma bonding MO (b) A pi antibonding MO (c) The MOs formed from combination of the 1s orbitals of two atoms?

The molecules N2 and CO are isoelectronic but their properties are quite different. Although as a first approximation we often use the same MO diagram for both, suggest how the MOs in N2 and CO might be different.

Use valence bond theory to explain the bonding in F2, HF, and CIBr. Sketch the overlap of the atomic orbitals involved in the bonds.

Strike-anywhere matches contain a layer of KClO3 and a layer of P4S3. The heat produced by the friction of striking the match causes these two compounds to react vigorously, which sets fire to the wooden stem of the match. KCIO3 contains the ClO3 ion. P4S3 is an unusual molecule with the skeletal structure. (a) Write Lewis structures for P4S3 and the ClO3 ion. (b) Describe the geometry about the P atoms, the S atom, and the Cl atom in these species. (c) Assign a hybridization to the P atoms, the S atom, and the Cl atom in these species. (d) Determine the oxidation states and formal charge of the atoms in P4S3 and the ClO3 ion.

The following is part of a molecular orbital energy-level diagram for MOs constructed from 1 s atomic orbitals. a) What labels do we use for the two MO s shown? b)For which of the following molecules or ions could this be the energy-level diagram: H2, He2, H2+,He2+, or H2-? C) What is the bond order of the molecule or ion? d) If an electron is added to the system,into which of the MOs will it be added?

How many electrons does it take to fill (a) the MOs formed from combination of the 2p orbitals of two atoms; (b) a s* 2p MO; (c) the MOs formed from combination of the 2s orbitals of two atoms?

E314 Inorganic Chemistry Key Questions 1. From the combination of the following orbitals in the orientations shown, sketch the bonding and anti- bonding molecular orbitals that should result. Indicate whether the MO's are o or . It is possible that the combination could be non-bonding. a) . b) P c) d) O

Use the template below to construct a MO diagram for the CN* molecule and use it to answer the following questions. In the completed diagram for CN*, the number of electrons in bonding orbitals is: in antibonding orbitals is: What is the bond order? If a fraction is needed, use a decimal number. CN* is Molecular orbitals Atomic orbitals (Atom A) Atomic orbitals (Atom B) 2p Encrgy

The atomic orbital, AO, contributions of penta-1,3-dienyl cation (shown to the right) are drawn in random order below. Using the A-E labels: (a) match the AO contributor to the MO energy diagram levels, (b) next to the MO diagram levels, identify each π MO as either bonding, nonbonding, or antibonding, (c) populate the T electrons in the appropriate MO energy levels, and (d) label the HOMO and the LUMO. 8 8 8 8 A (11 o* MOs) |||| (11 g Mos) B с D E

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