The element niobium has bcc packing with a body-centered cubic unit cell. The volume of the unit cell is 3.59 x 10-26 L. Calculate the density (g/cm3) of the element

Answer 1

In each cell the number of atoms is:
1 center
1/8 of each corner, or 1/8 *8 total atoms=1 atom

density=mass of 2 atoms Noibium/volume