$KCl$ 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:

Copper crystallizes in an $fcc$ lattice with a unit cell edge length of $361 \ pm$. What is the radius of the copper atom in $pm$?

The edge length of the unit cell of a metal $(M_w = 24 \ g \ mol^{-1})$ having a cubic structure is $4.53 \ \mathring{A}$. If the density of the metal is $1.74 \ g \ cm^{-3}$, the radius of the metal atom is ............... $pm$ $(N_A = 6 \times 10^{23} \ mol^{-1})$

$A$ metal has a $fcc$ lattice. The edge length of the unit cell is $404 \, pm$. The density of the metal is $2.72 \, g \, cm^{-3}$. The molar mass of the metal is :- ............ $g \, mol^{-1}$ ( $N_A$ Avogadro constant $= 6.02 \times 10^{23} \, mol^{-1}$ )

Calculate the radius of a metal atom if it forms a $bcc$ unit cell having an edge length of $530 \ pm$. (in $pm$)

$A$ metal $(X)$ of atomic weight $M \ g \ mol^{-1}$ crystallizes in a $bcc$ lattice. Its density is $d \ g \ cm^{-3}$. What is the equation for the unit cell edge length $(a)$? ($N=$ Avogadro number)