Chemistry - Solid State Question with Solution | TestHub

A tetrahedral void is formed when a sphere of the $2^{\text{nd }}$ layer is present above the triangular void of the $1^{\text{st }}$ layer.

All the triangular voids are not covered by the spheres of the $2^{\text{nd }}$ layer.

Tetrahedral voids are formed when the triangular voids in the $2^{\text{nd }}$ layer lie above the triangular voids in the $1^{\text{st }}$ layer and the triangular voids in the $1^{\text{st }}$ layer and the triangular shapes of these voids do not overlap.

Octahedral voids are formed when the triangular voids in the $2^{\text{nd }}$ layer exactly overlap with similar voids in the $1^{\text{st }}$ layer.