Question

How do you find the coordination number of sodium chloride $\left(\mathrm{NaCl}\right)$?

Answer 1

Sodium chloride:

1. The number of atoms surrounding an atom in its crystal lattice structure is known as the coordination number of that atom.
2. We have$\mathrm{NaCl}$, an ionic solid with a stoichiometric ratio of$1:1$, which means that one sodium ion must combine with one chloride ion.
3. This indicates that this cation and anion are in the same number and have the same number of ions linked to them.
4. Because the unit cell of $\mathrm{NaCl}$ is FCC i.e. face-centered, an ion is present at each of the lattice's four corners and six faces.
5. This indicates that one Na+ or Cl ion will be surrounded by six ions from above, below, ahead, behind, to the right, and to the left. In$\mathrm{NaCl}$, ${\mathrm{Na}}^{+}$ is surrounded by $6$$\mathrm{Cl}$ ions, whereas $\mathrm{Cl}$ is surrounded by $6$${\mathrm{Na}}^{+}$ ions.

Therefore, the coordination number of sodium chloride is $6$.