$A$ cubic unit cell contains manganese ions at the corners and fluoride ions at the centres of each edge. The coordination number of the manganese ion is-

The number of equidistant oppositely charged ions in a sodium chloride crystal is

What is the total number of atoms in a $BCC$ crystal lattice having $1.8 \times 10^{20}$ unit cells?

In a face-centered cubic $(FCC)$ lattice,$A$ atoms are present at the corners and $B$ atoms are present at the face centers. If one $B$ atom is removed from one of the face centers,what will be the molecular formula of the compound?

If the radius ratio is in the range of $0.414 - 0.732,$ then the coordination number will be

The radius of a calcium ion is $94 \text{ pm}$ and of the oxide ion is $146 \text{ pm}$. The possible crystal structure of calcium oxide will be