Question

Number of atom per unit cell in B.C.C.

• A. 9
• B. 4
• C. 2
• D. 1

Answer 1

Answer: (C)

2

Answer 2

The correct option is (C) : 2

In BCC, the cube's body centre and corners are occupied by lattice atoms. A cube contains 8 corners, each of which contributes $\frac{1}{8}$ of the total. The effective number of atoms per cube = $\frac{1}{8}$×8 = 1. Additionally, each cube will contain one body centre, and a body centre will have a contribution of 1. Therefore, the actual number of atoms in a cube is 1. So, the BCC has a total of 1+1=2 atoms.