$NaCl$ has $4$ formula units per unit cell. If the edge length of the unit cell is $0.564 \, nm$,then the density of the crystal is ............ $\text{g/cm}^3$. $(NaCl = 58.5 \, \text{g/mol})$

$CsCl$ crystallises in a cubic structure that has $Cl^{-}$ at each corner and $Cs^{+}$ at the centre of the unit cell. If $r_{Cs^{+}} = 1.69 \ \mathring{A}$ and $r_{Cl^{-}} = 1.81 \ \mathring{A}$,what is the value of the edge length of the cube in $\mathring{A}$?

Sodium crystallizes in $bcc$ structure with radius $1.86 \times 10^{-8} \text{ cm}$. What is the edge length of unit cell of sodium?

An ionic compound $X^{+}Y^{-}$ has a $bcc$ structure. The distance between two nearest ions is $1.73 \, \mathring{A}$. What would be the edge length of the unit cell in $pm$?

$NH_4Cl$ crystallizes in a $bcc$ lattice. If the edge length of the unit cell is $387 \, pm$, the distance between oppositely charged ions is ........ $pm$.

Gold crystallizes in an $fcc$ unit cell with an edge length of $408 \text{ pm}$. What is the radius of the gold atom (in $\text{ pm}$)?