Summary:
- The coordination number is the number of ions that immediately surround an ion of the opposite charge within a crystal lattice.
- Because the formula unit of sodium chloride displays a 1:1 ratio between the ions, the coordination numbers must be the same.
- In a cesium chloride crystal, the Cs+ ion occupies the center, while the chloride ions occupy each corner of the cube.
- CsCl and NaCl do not adopt identical crystal packing arrangements because the C's+ ion is considerably larger than the Na+ ion.
- The color of a compound is affected by the specific materials coordinated to that central ion.