The structure of $TlCl$ is similar to $CsCl$. What is the coordination number of $Tl^{+}$?

In an $NaCl$ crystal,how many $Cl^{-}$ ions surround each $Na^{+}$ ion?

$Na$ and $Mg$ crystallise in $b.c.c.$ and $f.c.c.$ type crystals respectively. The number of atoms of $Na$ and $Mg$ present in the unit cell of their respective crystals is:

The vacant space in the $bcc$ unit cell is .............. $\%$

The structure of $MgO$ is similar to that of $NaCl$. What is the coordination number of $Mg^{2+}$?

What is the coordination number of a sphere in a simple cubic lattice?