Gary Horner Solutions for Chapter: Models, Exercise 5: Creative thinking skills

Magnesium oxide is made up of ${\mathrm{Mg}}^{2+}$ ions and ${\mathrm{O}}^{2–}$ ions. How does the amount of charge present on the ions in an ionic compound affect the melting and boiling points? Explain your reasoning.

The strength of an ionic bond is also dependent on the distance between the two ionic centres. How are the melting and boiling points are affected by the ionic radius of the interacting ions? Sodium chloride has a melting point of $801 °\mathrm{C}$ and a boiling point of $1,413°\mathrm{C}$. Caesium has a larger ionic radius than sodium, and iodine has a larger ionic radius than chlorine. How do the melting and boiling points of sodium chloride and caesium iodide compare? Explain your reasoning.