---
title: "Transition metal compounds frequently exhibit paramagnetism as a result of unpaired electrons in their valence d subshells. A chemist analyzes a crystalline salt containing isolated \\(\\text{Co}^{2+}\\) ions. Which row in the table correctly identifies the ground-state electron configuration and the number of unpaired electrons for a gaseous \\(\\text{Co}^{2+}\\) ion?"
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url: "https://nerd-notes.com/ubq/120168/"
date_modified: "2026-08-21T16:02:44+00:00"
---

# Transition metal compounds frequently exhibit paramagnetism as a result of unpaired electrons in their valence d subshells. A chemist analyzes a crystalline salt containing isolated \(\text{Co}^{2+}\) ions. Which row in the table correctly identifies the ground-state electron configuration and the number of unpaired electrons for a gaseous \(\text{Co}^{2+}\) ion?

Transition metal compounds frequently exhibit paramagnetism as a result of unpaired electrons in their valence d subshells. A chemist analyzes a crystalline salt containing isolated \(\text{Co}^{2+}\) ions. Which row in the table correctly identifies the ground-state electron configuration and the number of unpaired electrons for a gaseous \(\text{Co}^{2+}\) ion?

- **A.** | Ground-State Electron Configuration | Number of Unpaired Electrons | | :---: | :---: | | \([\text{Ar}]\,4s^2\,3d^5\) | \(5\) |
- **B.** | Ground-State Electron Configuration | Number of Unpaired Electrons | | :---: | :---: | | \([\text{Ar}]\,4s^2\,3d^5\) | \(1\) |
- **C.** | Ground-State Electron Configuration | Number of Unpaired Electrons | | :---: | :---: | | \([\text{Ar}]\,3d^7\) | \(1\) |
- **D.** | Ground-State Electron Configuration | Number of Unpaired Electrons | | :---: | :---: | | \([\text{Ar}]\,3d^7\) | \(3\) |

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120168/*