Given: Edge length of unit cell (a)
= 287 pm = 287 × 10−10 cm
= 2.87 x 10–8 cm
Density of iron (d) = 7.87 g/cm3
NA = 6.023 x 1023 atoms mol−1
Atomic mass of iron (M) = 55.845
To find: Number of iron atoms (z) = ?
Formula: i. V = a3
z = 2 atoms per unit cell.
Hence it is Face centred cubic structure (BCC)