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

How many atoms of niobium are present in $2.43 \ g$ if it forms $bcc$ structure with density $9 \ g \ cm^{-3}$ and volume of unit cell $2.7 \times 10^{-23} \ cm^3$?

Copper crystallises in $fcc$ structure with a unit cell length of $361 \ pm$. What is the radius of copper atom? ............ $pm$

Calculate the molar mass of a metal having a density of $22.24 \ g \ cm^{-3}$,which crystallizes to form a unit cell containing $4$ particles. Given $a^3 = 5.6 \times 10^{-23} \ cm^3$.

The substance $CuCl$ has a $ZnS$ $(ccp)$ structure. If its density is $3.4 \ g \ cm^{-3}$, what is the edge length of the unit cell?

$KF$ has a structure similar to $NaCl$. If the density of the crystal is $2.48 \, g/cm^3$, the distance between $K^+$ and $F^-$ ions will be ............. $pm$. (Atomic masses: $K = 39 \, amu, F = 19 \, amu$)