---
title: "In an investigation of first-row transition metal compounds, a student determines the electron configurations of several common metal cations. Which of the following cations has the ground-state electron configuration \\([\\text{Ar}]\\,3d^5\\)?"
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url: "https://nerd-notes.com/ubq/119605/"
date_modified: "2026-08-21T08:11:44+00:00"
---

# In an investigation of first-row transition metal compounds, a student determines the electron configurations of several common metal cations. Which of the following cations has the ground-state electron configuration \([\text{Ar}]\,3d^5\)?

In an investigation of first-row transition metal compounds, a student determines the electron configurations of several common metal cations. Which of the following cations has the ground-state electron configuration \([\text{Ar}]\,3d^5\)?

- **A.** \(\text{Fe}^{3+}\)
- **B.** \(\text{Fe}^{2+}\)
- **C.** \(\text{Mn}^{3+}\)
- **D.** \(\text{Cr}^{3+}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119605/*