The coordination number of an atom in a hexagonal close-packed $(hcp)$ structure is ...........

Explain the crystal structure of sodium chloride $(NaCl)$.

The structure of $ZnS$ is

Which of the following metals has a $ccp$ crystal structure?

The coordination number of a metal crystallizing in a hexagonal close-packed $(hcp)$ structure is:

$CsBr$ crystal has $bcc$ structure. It has an edge length of $4.3 \ \mathring{A}$. The shortest interionic distance between $Cs^{+}$ and $Br^{-}$ ions is ................ $\mathring{A}$.