Question

question 12 (2 points)
the radius ratio range for cubic coordination is...
0.155 - 0.225 (tiny cation to large anion)
0.225 - 0.414 (small cation to large anion)
0.732 - 1.0 (similar but smaller cation to anion)
1.0 (same size cations and anions)
1.0 - 1.4 (bigger cation than anion)

Explanation:

In ionic crystals, the radius - ratio rule helps determine the coordination number. For cubic coordination (coordination number = 8), the radius ratio ($\frac{r_{cation}}{r_{anion}}$) range is 0.732 - 1.0. This is based on geometric considerations of ion - packing in the crystal lattice.

Answer:

C. 0.732 - 1.0 (similar but smaller cation to anion)