An element (atomic mass $= 100 \ g/mol$) having $bcc$ structure has a unit cell edge of $400 \ pm$. The density of the element is ................. $g/cm^3$.

$X$-ray diffraction studies show that copper crystallises in an $fcc$ unit cell with cell edge of $3.608 \times 10^{-8} \ cm$. In a separate experiment,copper is determined to have a density of $8.92 \ g / cm^{3}$,calculate the atomic mass of copper.

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

The edge length of $fcc$ type unit cell of copper having atomic radius $127.6 \ pm$ is equal to (in $pm$)

Calculate the edge length of $fcc$ unit cell if the radius of the metal atom is $139 \ pm$.

Copper crystallises into a $fcc$ lattice with edge length $3.61 \times 10^{-8} \, cm$. Show that the calculated density is in agreement with its measured value of $8.92 \, g \, cm^{-3}$.