In a metal oxide,$O^{2-}$ ions are arranged in $hcp$ lattice while metal ions occupy $2/3$ of the octahedral voids. The simplest formula of the oxide is:

In a cubic close-packed $(ccp)$ structure,if there are $N$ spheres,what is the number of octahedral voids?

What is the total contribution of all corner particles in a $bcc$ unit cell?

In a compound $AB_2O_4$,the oxide ions form a cubic close-packed $(CCP)$ lattice. The molar ratio of trivalent cations to bivalent cations is $2:1$. If all the bivalent ions occupy octahedral voids and trivalent ions occupy both tetrahedral and octahedral voids in equal numbers,then the fraction of octahedral voids that remain unoccupied is:

Calculate the total volume occupied by all particles in an $fcc$ unit cell if the volume of the unit cell is $6.4 \times 10^{-23} \ cm^3$.

In an $A_{x} B_{y}$ crystal structure,$A$ atoms occupy all octahedral as well as all tetrahedral voids,and $B$ atoms are at the $FCC$ lattice points. What is the formula of the compound $A_{x} B_{y}$?