Question

An element A(Atomic weight = 100) having bcc structure has unit cell edge length 400 pm. Calculate the density of A and number of unit cells and number of atoms in 10 gm of A.

Answer 1

BCC structure 

Effective number of atoms = 2

= 1.927 x 10^–6 cm³

Volume of one unit = (4 x 10^–10)³ 

 = 64 x 10^–30 cm³

Number of unit cells

Number of atoms = 6.023 x 10²² atoms