A portion of a two-dimensional slab of NaCl (s) is shown here (see Figure 8.3) in which

Question:

A portion of a two-dimensional "slab" of NaCl (s) is shown here (see Figure 8.3) in which the ions are numbered.
(a) Of the following types of interactions (identified by color), which are attractive and which are repulsive: "purple-purple," "purple-green," "green-green"? Explain.
(b) Consider the "green-green" interactions between ions 1 and 3, ions 1 and 5, and ions 3 and 5.Which one or more of these three will result in the interaction of largest magnitude? Which one or more will result in the interaction of the smallest magnitude? (c) Consider the "green-green" interactions between ions 1 and 5 and the "green-purple" interactions between ions 1 and 2. Which of these will have the greater magnitude?
(d) Does your answer to part (c) help explain why NaCl is a stable ionic solid?