In a $NaCl$ crystal, the distance between $Na^{+}$ and $Cl^{-}$ ions is $a \ pm$. What is the edge length of the unit cell?

In a $ccp$ lattice of $X$ and $Y$,$X$ atoms are present at the corners while $Y$ atoms are at face centers. What would be the formula of the compound if one of the $X$ atoms from a corner is replaced by a $Z$ atom?

In an end-centered unit cell,the body diagonal contains two additional atoms. What is the total number of atoms present in the unit cell?

An element occurring in the $bcc$ structure has $12.08 \times 10^{23}$ unit cells. The total number of atoms of the element in these cells will be:

$A$ solid $AB$ has a $NaCl$ structure. $B$ atoms are at the corners and all face-centered positions of the unit cell,while $A$ atoms occupy all the $O.H.V.$ (Octahedral Voids). If all the atoms from the face-centered positions along one axis are removed,what will be the resulting stoichiometry of the solid?

If the coordination number of an element in its crystal lattice is $8$,what will be its packing structure?