---
title: "A student is asked to analyze the relative melting points of three binary ionic solids: \\(\\text{MgO}\\), \\(\\text{NaF}\\), and \\(\\text{NaCl}\\). Which of the following correctly ranks the melting points of these solids from highest to lowest and provides the correct justification?"
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url: "https://nerd-notes.com/ubq/119161/"
date_modified: "2026-08-19T12:32:31+00:00"
---

# A student is asked to analyze the relative melting points of three binary ionic solids: \(\text{MgO}\), \(\text{NaF}\), and \(\text{NaCl}\). Which of the following correctly ranks the melting points of these solids from highest to lowest and provides the correct justification?

A student is asked to analyze the relative melting points of three binary ionic solids: \(\text{MgO}\), \(\text{NaF}\), and \(\text{NaCl}\). Which of the following correctly ranks the melting points of these solids from highest to lowest and provides the correct justification?

- **A.** \(\text{NaCl} > \text{NaF} > \text{MgO}\), because larger ions create stronger lattice energies, and lower ion charges result in weaker repulsive forces within the crystal lattice.
- **B.** \(\text{MgO} > \text{NaCl} > \text{NaF}\), because \(\text{Cl}^-\)
- **C.** \(\text{MgO} > \text{NaF} > \text{NaCl}\), because \(\text{MgO}\) has higher ionic charges (\(+2/-2\)) than \(\text{NaF}\) and \(\text{NaCl}\) (\(+1/-1\)), and \(\text{F}^-\) has a smaller ionic radius than \(\text{Cl}^-\), resulting in a shorter internuclear distance.
- **D.** \(\text{MgO} > \text{NaF} > \text{NaCl}\), because the internuclear distance in \(\text{MgO}\) is shorter than in \(\text{NaF}\), which has a greater effect on lattice energy than the charges of the constituent ions.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119161/*