Explanation:
It is known that for a body centered cubic unit cell there are 2 atoms per unit cell.
This means that volume occupied by 2 atoms is equal to volume of the unit cell.
So, according to the volume density
![5 \times 10^{26} atoms = 1 [tex]m^{3}](https://tex.z-dn.net/?f=5%20%5Ctimes%2010%5E%7B26%7D%20atoms%20%3D%201%20%5Btex%5Dm%5E%7B3%7D)
2 atoms = 
= 
Formula for volume of a cube is
. Therefore,
Volume of the cube = 
As lattice constant (a) = 
= 
Therefore, the value of lattice constant is
.
And, for bcc unit cell the value of radius is as follows.
r = 
Hence, effective radius of the atom is calculated as follows.
r = 
= 
= 
Hence, the value of effective radius of the atom is
.