If the edge length of a unit cell of $Li$ is $351 \, pm$, what is the radius of $Li$ (in $pm$)?

What is the number of atoms in $1000 \ g$ of an $FCC$ crystal? Given density $= 10 \ g \ cm^{-3}$ and edge length $= 200 \ pm$.

$KCl$ has the same structure as $NaCl$. If ${r_{Na^+}}/{r_{Cl^-}} = 0.55$ and ${r_{Na^+}}/{r_{K^+}} = 0.74$,then the ratio of the edge lengths of $KCl$ and $NaCl$ is:

Calculate the number of unit cells in $1 \, g$ of sodium metal that crystallizes in a $bcc$ structure. $(Na = 23 \, amu)$

An element has a density of $6.8 \ g \ cm^{-3}$ and crystallizes in a $bcc$ structure with a unit cell edge length of $290 \ pm$. The number of atoms in $200 \ g$ of the element is:

Calculate the number of atoms in $1 \ g$ of a metal if it forms an $fcc$ crystal structure,given that $\varrho \times a^3 = 1.728 \times 10^{-22} \ g$.