---
title: "The valence electron configurations for three consecutive Period 3 elements are provided in the table below.  | Element | Atomic number | Valence electron configuration | |—|—|—| | \\(\\text{Mg}\\) | 12 | \\(3s^2\\) | | \\(\\text{Al}\\) | 13 | \\(3s^2 3p^1\\) | | \\(\\text{Si}\\) | 14 | \\(3s^2 3p^2\\) |  Which of the following correctly ranks the three elements in order of increasing first ionization energy?"
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url: "https://nerd-notes.com/ubq/119191/"
date_modified: "2026-08-19T12:39:16+00:00"
---

# The valence electron configurations for three consecutive Period 3 elements are provided in the table below.

| Element | Atomic number | Valence electron configuration |
|—|—|—|
| \(\text{Mg}\) | 12 | \(3s^2\) |
| \(\text{Al}\) | 13 | \(3s^2 3p^1\) |
| \(\text{Si}\) | 14 | \(3s^2 3p^2\) |

Which of the following correctly ranks the three elements in order of increasing first ionization energy?

The valence electron configurations for three consecutive Period 3 elements are provided in the table below.

| Element | Atomic number | Valence electron configuration |
|---|---|---|
| \(\text{Mg}\) | 12 | \(3s^2\) |
| \(\text{Al}\) | 13 | \(3s^2 3p^1\) |
| \(\text{Si}\) | 14 | \(3s^2 3p^2\) |

Which of the following correctly ranks the three elements in order of increasing first ionization energy?

- **A.** \(\text{Mg} < \text{Al} < \text{Si}\)
- **B.** \(\text{Mg} < \text{Si} < \text{Al}\)
- **C.** \(\text{Al} < \text{Mg} < \text{Si}\)
- **D.** \(\text{Al} < \text{Si} < \text{Mg}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119191/*