Chapter 8.2, Problem 3CP

Lattice energies are graphed for three series of compounds in which the ion charges are $\text{+2, -2; +2, -1; and +1, -1}$. The ions in each series of compounds are separated by different distances. Identify the series.

$\begin{array}{l}\text{a)}\hfill \\ \text{red +2, -2; blue +1, -1; green +2, -1}\hfill \\ \text{b)}\hfill \\ \text{red +2, -2; blue +2, -1; green +1, -1}\hfill \\ \text{c)}\hfill \\ \text{red +2, -1: blue +2, -2; green +1, -1}\hfill \\ \text{d)}\hfill \\ \text{red +1, -1; blue +2, -1; green +2, -2}\hfill \\ \text{e)}\hfill \\ \text{red +2, -1; blue +1, -1; green +2, -2}\hfill \end{array}$