Question

Niobium (Nb) has an atomic radios of 0.1430 nm and a density of 8.57 g/cm^3. Determine whether it has an FCC or a BCC crystal structure.

Answer 1

In order to determine whether Nb has an FCC or a BCC crystal structure, we need to compute its density for each of the crystal structures. For FCC, n = 4, its atomic weight is 92.91 g/mol.Thus, for FCC density = 9.33 g/cm³. From this result, it is clear that this value of density is not that provided in the problem statement, so the crystal structure for Nb is not FCC. So, for BCC n = 2. Thus, for BCC density = 8.57 g/cm³. This is the value provided in the above problem. Therefore, Nb has a BCC crystal structure.