---
title: "A student dissolves a sample of cobalt(II) chloride, \\(\\text{CoCl}_2\\text{(s)}\\), in distilled water to prepare an aqueous solution. Which of the following is the ground-state electron configuration of the \\(\\text{Co}^{2+}\\) ion present in the solution?"
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url: "https://nerd-notes.com/ubq/119180/"
date_modified: "2026-08-19T12:39:01+00:00"
---

# A student dissolves a sample of cobalt(II) chloride, \(\text{CoCl}_2\text{(s)}\), in distilled water to prepare an aqueous solution. Which of the following is the ground-state electron configuration of the \(\text{Co}^{2+}\) ion present in the solution?

A student dissolves a sample of cobalt(II) chloride, \(\text{CoCl}_2\text{(s)}\), in distilled water to prepare an aqueous solution. Which of the following is the ground-state electron configuration of the \(\text{Co}^{2+}\) ion present in the solution?

- **A.** \([\text{Ar}]\,3d^7\)
- **B.** \([\text{Ar}]\,4s^2\,3d^5\)
- **C.** \([\text{Ar}]\,4s^1\,3d^6\)
- **D.** \([\text{Ar}]\,4s^2\,3d^7\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119180/*