5. In a close-packed array containing N spheres, there are N octahedral holes and 2N tetrahedral holes. Use this information to answer the following: a) The structure of solid Al203 consists of an hcp array of oxide ions with the Al3+ ions in octahedral holes. What fraction of the octahedral holes contains Al3+ ions? b) The mineral spinel has the formula MgAl2O4. The structure is based on a ccp array of oxide ions with the Mg²+ ions in tetrahedral holes and the Al3+ ions in octahedral holes. What fraction of each type of hole is occupied by the respective ion?

5. In a close-packed array containing N spheres, there are N octahedral holes and 2N tetrahedral holes. Use this information to answer the following: a) The structure of solid Al203 consists of an hcp array of oxide ions with the Al3+ ions in octahedral holes. What fraction of the octahedral holes contains Al3+ ions? b) The mineral spinel has the formula MgAl2O4. The structure is based on a ccp array of oxide ions with the Mg²+ ions in tetrahedral holes and the Al3+ ions in octahedral holes. What fraction of each type of hole is occupied by the respective ion?

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter10: Liquids And Solids

Section: Chapter Questions

Problem 88E: A compound of cadmium, tin, and phosphorus is used in the fabrication of some semiconductors. It...

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