Chemistry 401

Intermediate Inorganic Chemistry

University of Rhode Island

Fall 1999

Exam 2

1. For each of the following species write the lowest energy Lewis structure, indicate the formal charge and oxidation number of each atom, show the geometric structure and estimate the bond angles, indicate the σ hybridization about the central atom, and give the point group. a) XeO3, b) XeOF2, c) SeF4.

2. Consider the molecular orbital diagram for NO, given below. This was constructed using only 2p orbitals as the basis set. Label the type of orbital (σ, π, δ, bonding, antibonding) at each energy level, show the orbital occupation, and find the bond order. Compare this to a Valence Bond Theory explanation of the bonding. What are the bond orders for NO+ and NO; would you expect these ions to be stable? Why or why not?

3. Mg is a metal, yet has a filled s orbital. Explain, in terms of band theory and appropriate atomic properties, why Mg can attain a partially filled band to give it metallic properties.

 

 

Answers