Chemistry 401

Intermediate Inorganic Chemistry

University of Rhode Island

Practice Problems

Exercises and Problems are from Shriver & Atkins, 4th edition. Some textbook examples have additional questions to the linked exercise or problem.

Solids, Ionic Bonding

Exercise 3.3

Problem 3.13

Exercise 3.9

Problem 3.4

Problem 3.5

Problem 3.8

1. Confirm that in rutile (TiO2) the stoichiometry is consistent with the structure. Answers

2. The promotion of an electron from the valence band into the conduction band in pure titanium(IV) oxide by light absorption requires a wavelength of less than 350 nm. Calculate the energy gap in electronvolts between the valence and conduction bands. Answers

3. When titanium(IV) oxide is heated in hydrogen, a blue color develops, indicating light absorption in the red. Does reduction of Ti(IV) to Ti(III) correspond to n-doping or p-doping? Answers

4. Gallium arsenide is a semiconductor that is widely used for the construction of the red-light-emitting displays and is under development for advanced central processor chips in supercomputers. If gallium arsenide (GaAs) is doped with selenium (on the As site), is it n-doped or p-doped? Answers

5. Estimate the lattice energy for magnesium chloride using both the Born-Landé equation and using a Born-Haber cycle. The heat of formation for magnesium chloride is –641.3 kJ/mole and the other thermodynamic data can be found in your textbook. In the Born-Landé equation, assume a fluorite structure, n= 8, and an interion distance of 2.4 Å. Compare the two values and comment about the agreement or disagreement. Answers

6. Look up the metallic radius for the first row transition metal elements (Sc to Zn) and explain the trend in terms of metallic bonding. Answers

7. Calculate the lattice energy (in units of kJ/mol) for ZnO in the wurtzite structure using the Born-Landé equation and using a Born-Haber cycle. Compare the two answers and comment on any differences. Useful data: the Born exponent, n, = 8; the sublimation energy of zinc = 130.4 kJ/mol; and the standard heat of formation of zinc(II) oxide = –350.5 kJ/mol. Other data can be found in the textbook. Answers

8. LiI is found to have the same structure as NaCl. Given this information, estimate the lattice energy for LiI using the Born-Mayer equation and d* = 34.5 pm. Radius ratio rules suggest that the the observed LiI structure is anomalous; explain why. Answers

9. In the context of band theory, explain why Mg is a metal, despite the fact that it has a filled s2 electron configuration. Answers