The coordination number of an atom in a body-centered cubic $(BCC)$ structure is:
[Assume that the lattice is made up of atoms.]

Potassium fluoride $(KF)$ has an $NaCl$ type structure. What is the distance between $K^{+}$ and $F^{-}$ ions if the unit cell edge length is $a \ cm$?

$A$ compound is formed by elements $A$ and $B$. Element $A$ occupies the corners of the cube,and element $B$ occupies the face centers. What is the formula of the compound?

What is the radius ratio $r^+/r^-$ for $NaCl$?

In a crystal of substance $A_xB_y$,$A$ atoms are present at each corner of the face-centered cubic $(FCC)$ unit cell,and $B$ atoms are present at each face center. What is the correct formula of the substance $A_xB_y$?

What is the coordination number of sodium ions in the case of sodium chloride structure?