Calculate the molar mass of an element having a density of $8.6 \ g \ cm^{-3}$ if it forms a $bcc$ structure $[a^3 \times N_{A} = 22.0 \ cm^3 \ mol^{-1}]$.

Copper crystallises in $fcc$ with a unit cell edge length of $361 \ pm$. What is the radius of the copper atom in $pm$?

The unit cell of copper corresponds to a face-centered cubic $(FCC)$ lattice with an edge length of $3.596 \, \mathring{A}$. The calculated density of copper in $kg / m^{3}$ is ....... .
[Molar mass of $Cu = 63.54 \, g/mol$; Avogadro Number $= 6.022 \times 10^{23} \, mol^{-1}$]

Sodium metal crystallizes in a body-centred cubic $(bcc)$ lattice with a unit cell edge of $4.29 \ \mathring{A}$. The radius of the sodium atom is approximately ............. $\mathring{A}$.

Ammonium chloride crystallizes in a body-centered cubic lattice with an edge length of the unit cell of $390 \ pm$. If the size of the chloride ion is $180 \ pm$,the size of the ammonium ion would be ........... $pm$.

The radius of $K^{+}$ is $133 \ pm$ and that of $Cl^{-}$ is $181 \ pm$. The volume of the unit cell of $KCl$ expressed in $10^{-22} \ cm^{3}$ is