What is the two-dimensional coordination number of a molecule in a square close-packed layer?

In a face-centered cubic lattice,a unit cell face is shared equally by how many unit cells?

Which of the following exhibits an $8:8$ coordination type packing?

The edge length of the unit cell of $NaCl$ crystal lattice is $552 \, pm$. If the ionic radius of the sodium ion is $95 \, pm$, what is the ionic radius of the chloride ion in $pm$?

In which of the following crystals are alternate tetrahedral voids occupied?

In an ${A^{+}}{B^{-}}$ ionic compound, the radii of ${A^{+}}$ and ${B^{-}}$ ions are $180 \ pm$ and $187 \ pm$ respectively. The crystal structure of this compound will be: