What is the number of unit cells present in $3.9 \ g$ of potassium if it crystallizes in $BCC$ structure?

What is the number of unit cells present in a cubic crystal lattice having $4$ atoms per unit cell and weighing $0.60 \ g$ (molar mass $60 \ g \ mol^{-1}$)?

$A$ metal crystallizes in both $fcc$ and $bcc$ lattice structures with unit cell edge lengths of $380 \ pm$ and $300 \ pm$ respectively. The ratio of their densities $(bcc/fcc)$ is:

What is the volume of $1$ mole of a crystalline solid having unit cell edge length $16 \times 10^{-8} \ cm$,if its unit cell contains $24$ molecules?

The distance between two nearest $Ag$ atoms is $2.5 \times 10^{-8} \ cm$. The density of its crystal is .......... $g/cm^3$. $(Ag = 108 \ g/mol)$

Calculate the volume of the unit cell for an element having a molar mass of $56 \ g \ mol^{-1}$ that forms $bcc$ unit cells. $\left[\rho \cdot N_{A} = 4.8 \times 10^{24} \ g \ cm^{-3} \ mol^{-1}\right]$