$Cu$ metal crystallizes in an $fcc$ or $ccp$ lattice. If the edge length of its unit cell is $361 \ pm$, what is the radius of the $Cu$ atom (in $pm$)?

What is the number of atoms present per unit cell of aluminium having edge length $4 \ \mathring{A}$? (Given: density of $Al = 2.7 \ g \ cm^{-3}$,atomic mass of $Al = 27 \ g \ mol^{-1}$)

Calculate the number of unit cells in $10 \, g$ of $CsCl$ which crystallizes in a $bcc$ structure. $(CsCl = 168.5 \, amu)$

Calculate the number of unit cells in $0.5 \text{ g}$ of a metal if the product of the volume and density of the unit cell is $6.65 \times 10^{-23} \text{ g}$.

An element (molar mass $180 \ g \ mol^{-1}$) has a $BCC$ crystal structure with a density of $18 \ g \ cm^{-3}$. What is the edge length of the unit cell?

Niobium crystallizes in a $bcc$ structure. If its density is $8.55 \, g/cm^3$, calculate the atomic radius of niobium. [Atomic mass of $Nb = 93 \, u$] (in $pm$)