Question

What is the total volume of the particles present in a body centered unit cell?

• A. $8\pi r^3$
• B. $\frac{8}{3}\pi r^3$
• C. $\frac{16}{3}\pi r^3$
• D. $\frac{32}{3}\pi r^3$

Answer 1

The correct option is B $\frac{8}{3}\pi r^3$

Since particles are assumed to be spheres, volume of one sphere is $\frac{4}{3}\pi r^3$, total volume of all particles in BCC = $2\times \frac{4}{3}\pi r^3=\frac{8}{3}\pi r^3$ since a BCC has 2 particles per unit cell.