Identify the unit cell from the following that contains four particles in it.

What is the value of the radius ratio for an ionic crystal having a coordination number of $6$?

Explain the calculation of the number of atoms in a primitive cubic unit cell.

An element has a $bcc$ structure with $12.08 \times 10^{23}$ unit cells. What is the total number of atoms in these unit cells?

In a mixed oxide of two metals $X$ and $Y$,divalent $X^{2+}$ ions occupy $50\%$ of the tetrahedral voids,while trivalent $Y^{3+}$ ions occupy $50\%$ of the octahedral voids. The formula of the oxide is:

Total volume of atoms present in a face-centred cubic unit cell of a metal is ($r$ is atomic radius)