Calculate the volume occupied by a particle in $fcc$ unit cell if the volume of the unit cell is $1.6 \times 10^{-23} \ cm^3$.

Write a note on interstitial sites or voids.

The number of octahedral and tetrahedral holes respectively present in a hexagonal close packed $(hcp)$ crystal of $X$ atoms are

The anions $(A)$ of a $C_{p}A_{q}$ molecule form an $fcc$ lattice. Cations $(C)$ are positioned at the body center and half of the edge centers. The formula of the molecule is:

$A$ metal crystallises in an $FCC$ lattice with $ABCABC...$ packing. If the distance between the nearest neighbours is '$a$',then the distance between the centres of the nearest triangular voids of two consecutive layers is:

$A$ solid has an $hcp$ lattice. Atoms of $Z$ (anions) form the $hcp$ lattice. Atoms of $X$ (cations) occupy all the octahedral voids in the lattice. Atoms of $Y$ (cations) occupy half of the tetrahedral voids. What is the molecular formula of the solid?