Niobium crystallizes in a body-centered cubic unit cell.If the radius of a niobium atom is 0.145 nm,what is the length of an edge of the unit cell?

Question

Quizplus · Accepted Answer

For a body-centered cubic unit cell, the edge length, a, can be calculated as:
a = 4r/√3
where r is the radius of the atom. 
Substituting the given values, 
a = 4(0.145 nm)/√3
a = 0.335 nm, which is closest to choice C.

Niobium Crystallizes in a Body-Centered Cubic Unit Cell