Potassium has a $bcc$ structure with a nearest neighbour distance of $4.52 \ \mathring{A}$. Its atomic weight is $39$. Its density (in $kg \ m^{-3}$) will be:

The edge length of the unit cell of a crystal is $288 \ pm$. If its density is $7.2 \ g \ cm^{-3}$ and the molar mass is $52 \ g \ mol^{-1}$, determine the type of unit cell.

If the edge length of the unit cell of an element crystallizing in a $bcc$ structure is $400 \, pm$, then the density of the crystal will be ............ $\text{g/cm}^3$. (Atomic weight $= 100 \, \text{g/mol}$)

Lithium metal crystallises in a body-centred cubic crystal. If the length of the side of the unit cell of lithium is $351 \ pm,$ the atomic radius of lithium will be $............$ $pm$.

Sodium crystallises in $bcc$ structure with radius $1.86 \times 10^{-8} \ cm$. Calculate the edge length of the unit cell.

At $T \ K$,copper (atomic mass $= 63.5 \ u$) has $fcc$ unit cell structure with edge length of $x \ \mathring{A}$. What is the approximate density of $Cu$ in $g \ cm^{-3}$ at that temperature? $(N_A = 6.0 \times 10^{23} \ mol^{-1})$