Question

The number of spheres contained (i) in one body centred cubic unit cell and (ii) in one face centred cubic unit cell, is

Answer 1

The simplest crystal structures are those in which there is only a single atom at each lattice point. In the bcc structures the spheres fill 68 % of the volume. The number of atoms in a unit cell is two (8 × 1/8 + 1 = 2). There are 23 metals that have the bcc lattice.