How many unit cells are present in a cube-shaped ideal crystal of $NaCl$ of mass $1.00 \ g$? [Atomic masses: $Na = 23, Cl = 35.5$]

Which is the volume of unit cell of a metal (atomic mass $25 \ g \ mol^{-1}$) having $BCC$ structure and density $3 \ g \ cm^{-3}$?

Gold (edge length $0.144 \ nm$) crystallizes in a face-centered cubic unit cell. What is the radius $(r)$ of the gold atom in $pm$?

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 $\text{ g/mol}$)

In the Bragg's equation for diffraction of $X$-rays, $n$ represents:

How can you determine the atomic mass of an unknown metal if you know its density and the dimension of its unit cell? Explain.