---
title: "The successive ionization energies for gaseous sodium atoms are shown in the table below.  | Ionization | Process | Ionization energy \\(\\left(\\text{kJ/mol}\\right)\\) | | :— | :— | :— | | First \\(\\left(IE_1\\right)\\) | \\(\\text{Na(g)} \\rightarrow \\text{Na}^+\\text{(g)} + e^-\\) | \\(496\\) | | Second \\(\\left(IE_2\\right)\\) | \\(\\text{Na}^+\\text{(g)} \\rightarrow \\text{Na}^{2+}\\text{(g)} + e^-\\) | \\(4562\\) | | Third \\(\\left(IE_3\\right)\\) | \\(\\text{Na}^{2+}\\text{(g)} \\rightarrow \\text{Na}^{3+}\\text{(g)} + e^-\\) | \\(6910\\) |  Which of the following statements best accounts for why the second ionization energy of \\(\\text{Na}\\) is nearly ten times greater than its first ionization energy?"
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url: "https://nerd-notes.com/ubq/119607/"
date_modified: "2026-08-21T16:01:02+00:00"
---

# The successive ionization energies for gaseous sodium atoms are shown in the table below.

| Ionization | Process | Ionization energy \(\left(\text{kJ/mol}\right)\) |
| :— | :— | :— |
| First \(\left(IE_1\right)\) | \(\text{Na(g)} \rightarrow \text{Na}^+\text{(g)} + e^-\) | \(496\) |
| Second \(\left(IE_2\right)\) | \(\text{Na}^+\text{(g)} \rightarrow \text{Na}^{2+}\text{(g)} + e^-\) | \(4562\) |
| Third \(\left(IE_3\right)\) | \(\text{Na}^{2+}\text{(g)} \rightarrow \text{Na}^{3+}\text{(g)} + e^-\) | \(6910\) |

Which of the following statements best accounts for why the second ionization energy of \(\text{Na}\) is nearly ten times greater than its first ionization energy?

The successive ionization energies for gaseous sodium atoms are shown in the table below.

| Ionization | Process | Ionization energy \(\left(\text{kJ/mol}\right)\) |
| :--- | :--- | :--- |
| First \(\left(IE_1\right)\) | \(\text{Na(g)} \rightarrow \text{Na}^+\text{(g)} + e^-\) | \(496\) |
| Second \(\left(IE_2\right)\) | \(\text{Na}^+\text{(g)} \rightarrow \text{Na}^{2+}\text{(g)} + e^-\) | \(4562\) |
| Third \(\left(IE_3\right)\) | \(\text{Na}^{2+}\text{(g)} \rightarrow \text{Na}^{3+}\text{(g)} + e^-\) | \(6910\) |

Which of the following statements best accounts for why the second ionization energy of \(\text{Na}\) is nearly ten times greater than its first ionization energy?

- **A.** The second electron is removed from an ion with a greater nuclear charge, because the loss of the first electron increases the number of protons in the nucleus that attract the remaining electrons.
- **B.** The second electron is removed from the \(n = 2\) core energy level rather than the \(n = 3\) valence level, experiencing significantly less shielding from inner electrons and a smaller average distance from the nucleus.
- **C.** The second electron experiences increased electron-electron repulsions within the smaller \(\text{Na}^+\) ion, requiring a large input of energy to overcome the repulsive forces among core electrons.
- **D.** The second electron is removed from the \(3s\) subshell of \(\text{Na}^+\), where it experiences identical shielding by the \(10\) core electrons but a slightly reduced ionic radius.

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