How many Br^- ions are around each K⁺ ion in KBr,which has a cubic unit cell with Br^- ions on each corner and each face? A)1 B)4 C)6 D)8

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Quizplus · Accepted Answer

Each Br^- ion on a corner is shared by 8 adjacent unit cells, and each ion on a face is shared by 2 adjacent unit cells. Therefore, the total number of Br^- ions in the unit cell is: 8 corners × 1/8 ion per corner + 6 faces × 1/2 ion per face = 4 ions Since KBr has a 1:1 ratio of K+ to Br-, there must be 4 K+ ions in the unit cell as well. Each K+ ion is surrounded by 6 Br- ions, and each Br- ion is surrounded by 6 K+ ions, so the coordination number of K+ and Br- ions is both 6. Therefore, there are 6 Br^- ions around each K⁺ ion in KBr.

How Many Br- Ions Are Around Each K+ Ion in KBr,which

How Many Br^- Ions Are Around Each K⁺ Ion in KBr,which