The density of $KBr$ is $2.75 \, g \, cm^{-3}$ and the unit cell edge length is $654 \, pm$. Given the atomic masses $K = 39$ and $Br = 80$, what is the crystal structure of $KBr$?

Polonium (atomic mass = $209$) crystallises in a simple cubic structure with a density of $9.32 \ g \ cm^{-3}$. Its lattice parameter (in $pm$) is closest to:

The number of atoms in $100 \ g$ of an $fcc$ crystal with density $d = 10 \ g/cm^3$ and cell edge equal to $100 \ pm$ is equal to

$A$ solid has a $bcc$ structure. If the distance of nearest approach between two atoms is $1.73 \, \mathring{A}$, the edge length of the cell is ........... $pm$.

In a cubic unit cell of an ionic compound, the eight corners are occupied by anions and cations are at the center of the cube. Calculate the volume of the unit cell if the density of the unit cell is $4 \text{ g cm}^{-3}$. [Molar mass of compound $= 168.6 \text{ g mol}^{-1}$ and $N_A = 6.022 \times 10^{23} \text{ mol}^{-1}$]

Potassium metal crystallizes in a face-centered cubic $(FCC)$ lattice. If the edge length of the unit cell is $0.574 \ nm$,what is the shortest distance between any two potassium nuclei (in $nm$)?