Question

A unit cell has one atom at each corner of cube and two atoms at one of its body diagonal

Answer 1

There are four body diagonals in a cube. As there are two atoms on each diagonal, there are a total of 4 x 2 = 8 atoms on the diagonals. These 8 atoms are within the body of the cubic unit cell and are not shared by other units.

Answer 2

There are four body diagonals in a cube. As there are two atoms on each diagonal, there are a total of 4 x 2 = 8 atoms on the diagonals. These 8 atoms are within the body of the cubic unit cell and are not shared by other units.