(Solved): Calcium sulfide \( (\mathrm{CaS}) \) adopts the crystal structure shown below. The yellow spheres a ...

Calcium sulfide \( (\mathrm{CaS}) \) adopts the crystal structure shown below. The yellow spheres are \( \mathrm{S}^{2-} \) anions and the grey spheres are \( \mathrm{Ca}^{2+} \) cations. How many \( \mathrm{Ca}^{2+} \) ions are there per \( \mathrm{CaS} \) unit cell? \( \mathrm{Ca}^{2+} \) ions per \( \mathrm{CaS} \) unit cell: