$Xe$ crystallizes in an $fcc$ structure. If the edge length of the unit cell of $Xe$ is $620 \, pm$, then the distance between two nearest $Xe$ atoms is .............. $pm$.

$A$ compound contains $Ca, Ti$ and $O$ elements. If $Ca^{2+}$ ions are at the corners of the cube,$Ti$ ions are at the body center,and $O^{2-}$ ions are at the face centers,then the molecular formula of the compound and the oxidation state of $Ti$ are respectively ........

The volume occupied by all the particles in a $B.C.C.$ unit cell is

In a compound,$W$ atoms are at the corners of the unit cell,$O$ atoms are at the edges of the unit cell,and $Na$ atoms are at the body center. The molecular formula of the compound is:

An oxide of $A$ crystallizes with $8$ atoms at the corners of the unit cell and $18$ oxygen atoms on the edges and on the faces symmetrically. What is the formula of this oxide?

What is the mass of a $bcc$ type unit cell of sodium if the mass of one atom of sodium is $3.819 \times 10^{-23} \ g$?