Calculate the number of unit cells in $1 \, g$ of $NaCl$ crystal,which crystallizes in an $fcc$ structure. (Molar mass of $NaCl = 58.5 \, g/mol$)

Calculate the number of unit cells in $1 \ cm^3$ of an element if the unit cell edge length is $2.0 \times 10^{-8} \ cm$.

An element occurs in the body-centred cubic $(BCC)$ structure with an edge length of $288 \ pm$. The density of the element is $7.2 \ g \ cm^{-3}$. The number of atoms present in $208 \ g$ of the element is nearly:

$CsCl$ 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 $\mathring{A}$?

$Au$ crystallizes in an $fcc$ lattice. If the edge length of the unit cell is $4.07 \ \mathring{A}$,then the distance between two nearest $Au$ atoms is ............... $\mathring{A}$.

Which method is used to determine the edge length of a unit cell?