Question

In $NaCl$ structure, $N{a}^{+}$ ions are present at:

• A. All tetrahedral voids
• B. All octahedral voids
• C. Corners as well as face centres of the cube
• D. Corners of the cube

Answer 1

The correct option is B All octahedral voids

In $NaCl,C{l}^{-}$ ions forms fcc structure lattice. $C{l}^{-}$ present at the corners and face centres of the cube.
Here, $N{a}^{+}$ ions occupies all the octahedral voids. The octahedral voids are present at the edge centres and body centre of the unit cell.
The coordination number of $NaCl$ is $6:6$