An element has a body-centered cubic $(bcc)$ structure with a cell edge of $288 \ pm$. The atomic radius is $...... \ pm$.

$A$ copper complex crystallising in a $CCP$ lattice with a cell edge of $0.4518 \ nm$ has been revealed by employing $X$-ray diffraction studies. The density of the copper complex is found to be $7.62 \ g \ cm^{-3}$. The molar mass of the copper complex is $..... \ g \ mol^{-1}$. (Nearest integer)
[Given : $N_{A} = 6.022 \times 10^{23} \ mol^{-1}$]

$KF$ 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: $K = 39 \, amu, F = 19 \, amu$)

Find the radius of a metal atom in a $bcc$ unit cell having an edge length of $450 \ pm$. (in $pm$)

If the edge length of a cubic unit cell in a $bcc$ structure is $400 \, pm$, then the atomic radius of the metal will be ........... $pm$.

Aluminium crystallises in a cubic close-packed structure. Its metallic radius is $125 \ pm$.
$(i)$ What is the length of the side of the unit cell?
$(ii)$ How many unit cells are there in $1.00 \ cm^3$ of aluminium?