---
title: "The table below provides the ionic charges and estimated ionic radii for four hypothetical ions that form the gaseous ion pairs \\(\\text{MX}\\) and \\(\\text{QZ}\\).  | Ion | Charge | Ionic radius (\\(\\text{pm}\\)) | | :— | :—: | :—: | | \\(\\text{M}^+\\) | \\(+1\\) | \\(160\\) | | \\(\\text{X}^-\\) | \\(-1\\) | \\(140\\) | | \\(\\text{Q}^{2+}\\) | \\(+2\\) | \\(80\\) | | \\(\\text{Z}^{2-}\\) | \\(-2\\) | \\(120\\) |  A simplified model treats the electrostatic attractive force, \\(F\\), between an isolated cation and an isolated anion as being governed by Coulomb’s law, where \\(F \\propto \\dfrac{|q_1 q_2|}{d^2}\\) and \\(d = r_{\\text{cation}} + r_{\\text{anion}}\\). Based on the information in the table, what is the value of the ratio \\(\\dfrac{F_{\\text{MX}}}{F_{\\text{QZ}}}\\)?"
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url: "https://nerd-notes.com/ubq/123465/"
date_modified: "2026-09-28T11:59:51+00:00"
---

# The table below provides the ionic charges and estimated ionic radii for four hypothetical ions that form the gaseous ion pairs \(\text{MX}\) and \(\text{QZ}\).

| Ion | Charge | Ionic radius (\(\text{pm}\)) |
| :— | :—: | :—: |
| \(\text{M}^+\) | \(+1\) | \(160\) |
| \(\text{X}^-\) | \(-1\) | \(140\) |
| \(\text{Q}^{2+}\) | \(+2\) | \(80\) |
| \(\text{Z}^{2-}\) | \(-2\) | \(120\) |

A simplified model treats the electrostatic attractive force, \(F\), between an isolated cation and an isolated anion as being governed by Coulomb’s law, where \(F \propto \dfrac{|q_1 q_2|}{d^2}\) and \(d = r_{\text{cation}} + r_{\text{anion}}\). Based on the information in the table, what is the value of the ratio \(\dfrac{F_{\text{MX}}}{F_{\text{QZ}}}\)?

The table below provides the ionic charges and estimated ionic radii for four hypothetical ions that form the gaseous ion pairs \(\text{MX}\) and \(\text{QZ}\).

| Ion | Charge | Ionic radius (\(\text{pm}\)) |
| :--- | :---: | :---: |
| \(\text{M}^+\) | \(+1\) | \(160\) |
| \(\text{X}^-\) | \(-1\) | \(140\) |
| \(\text{Q}^{2+}\) | \(+2\) | \(80\) |
| \(\text{Z}^{2-}\) | \(-2\) | \(120\) |

A simplified model treats the electrostatic attractive force, \(F\), between an isolated cation and an isolated anion as being governed by Coulomb's law, where \(F \propto \dfrac{|q_1 q_2|}{d^2}\) and \(d = r_{\text{cation}} + r_{\text{anion}}\). Based on the information in the table, what is the value of the ratio \(\dfrac{F_{\text{MX}}}{F_{\text{QZ}}}\)?

- **A.** \(\dfrac{1}{9}\)
- **B.** \(\dfrac{1}{6}\)
- **C.** \(\dfrac{4}{9}\)
- **D.** \(\dfrac{9}{16}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123465/*