Chemistry - Solid State Question with Solution | TestHub

$\begin{array}{rl}& \text{ Number of atoms }=\frac{\text{ Mass }}{\text{ Atomicmass }}\times {\mathrm{N}}_{\mathrm{A}}=\frac{3.9}{39}\times {\mathrm{N}}_{\mathrm{A}}=0.1{\mathrm{N}}_{\mathrm{A}}\\ & \text{ In BCC unit cell, }\mathrm{n}=2\\ & \therefore \text{ Number of unit cells }=\frac{0.1{\mathrm{N}}_{\mathrm{A}}}{2}=\frac{{\mathrm{N}}_{\mathrm{A}}}{20}\end{array}$