Question

What are the coordination numbers of each of the ions present in the cubic close-packed structure of $N{a}_{2}O$ at ordinary temperature and pressure?

Answer 1

Given CCP structure $N{a}_{2}O$

Which each anion $O^{2-}$ is surrounded by $8N{a}^{+}$ ions and each cation $N{a}^{+}$ is surrounded by $4O^{2-}$ ions. Coordination numbers of $N{a}^{+}$ and $O^{2-}$ are $4$ and $8$ respectively.