Aluminium crystallises in a face-centred cubic structure, its atomic radius is $125 \text{ pm}$. What is the edge length of the unit cell (in $\text{pm}$)?

An element crystallizes in an $fcc$ structure with an edge length of $200 \, pm$. If $200 \, g$ of this element contains $24 \times 10^{23}$ atoms,calculate its density in $g \, cm^{-3}$.

$KCl$ has the same structure as $NaCl$. If ${r_{Na^+}}/{r_{Cl^-}} = 0.55$ and ${r_{Na^+}}/{r_{K^+}} = 0.74$,then the ratio of the edge lengths of $KCl$ and $NaCl$ is:

The density of the unit cell of $Li$ is $0.539 \ g/cm^3$ and the edge length of the unit cell is $3.5 \ \mathring{A}$. How many $Li$ atoms are present in a unit cell of lithium? (Atomic mass of $Li = 6.94 \ g/mol$)

Suppose the mass of a single $Ag$-atom is $m$. $Ag$ metal crystallises in $fcc$ lattice with unit cell of length $a$. The density of $Ag$ metal in terms of $a$ and $m$ is

$A$ metal $(M)$ crystallizes in an $fcc$ lattice with an edge length of $4.242 \mathring{A}$. What is the radius of the $M$ atom (in $\mathring{A}$)?