An element with density $2.8 \ g \ cm^{-3}$ forms an $fcc$ unit cell having an edge length of $4 \times 10^{-8} \ cm$. Calculate the molar mass of the element.

An element crystallises in an $fcc$ unit cell with a cell edge length of $3.608 \times 10^{-8} \text{ cm}$. The density of the element is $8.92 \text{ g cm}^{-3}$. Calculate the atomic mass of the element $(N_A = 6.022 \times 10^{23} \text{ mol}^{-1})$. (in $\text{ g/mol}$)

Sodium metal crystallizes in $B.C.C.$ lattice with an edge length of $4.29 \ \mathring{A}$. The radius of the sodium atom is:

The density of $\beta-Fe$ is $7.6 \ g \ cm^{-3}$. It crystallizes in a cubic lattice with $a = 290 \ pm$. What is the value of $Z$? $(Fe = 56 \ g \ mol^{-1}; N_{A} = 6.022 \times 10^{23} \ mol^{-1})$

$Xe$ crystallizes in an $FCC$ structure. The edge length of its unit cell is $620 \, pm$. The radius of $Xe$ is $=$ ...... $pm$.

Bragg's law is given by the equation