Potassium bromide crystallizes in the rock salt structure. It has a density of 2.75 g/cm³. What is the edge length of the unit cell? In the rock salt structure, the bromide ions form an fcc unit cell, and the potassium ions occupy the octahedral holes. A)220 pm B)330 pm C)440 pm D)550 pm E)660 pm

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Quizplus · Accepted Answer

The rock salt structure has 4 formula units per unit cell. Using the density formula and the molar mass of KBr, the edge length can be calculated. The calculated edge length is approximately 660 pm.

Potassium Bromide Crystallizes in the Rock Salt Structure