Gallium crystallizes in a primitive cubic unit cell. the length of an edge of this cube is 362 pm. what is the radius of a gallium atom?

In a primitive cubic unit cell, there is one atom per unit cell. And 1/4 of the atom can be found in the corners of the cell. Therefore, one length of the cubic unit cell constitutes 2 radii. The radius of an atom of Gallium would be 362 pm / 2 = 181 pm. 

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