What is the total number of unit cells shared by each corner particle of a $bcc$ unit cell?

The edge length of a face-centered cubic unit cell of an ionic substance is $508 \ pm$. If the radius of the cation is $110 \ pm$, what is the radius of the anion in $pm$?

$A^{+}B^{-}$ shows rock salt type arrangement. Edge length of unit cell is $6 \ \mathring{A}$. If radius of $A^{+}$ is $1 \ \mathring{A}$,then the incorrect option is:

The coordination number of the sphere in cubic close packed $(ccp)$ structure is

Coordination numbers of $Zn^{2+}$ and $S^{2-}$ in the crystal structure of wurtzite are

In sodium chloride crystal,the number of next nearest neighbours of each $Na^{+}$ ion is