What is neon's electron configuration?

Neon's full electron configuration is 1s² 2s² 2p⁶. The first energy level holds 2 electrons in the 1s orbital, and the second energy level holds 8 electrons: 2 in the 2s orbital and 6 distributed equally across the three 2p orbitals (2p₋₁, 2p₀, 2p₊₁), each holding 2 electrons.

What is the abbreviated (noble-gas) electron configuration of neon?

Neon itself is a noble gas, so its configuration cannot be abbreviated using an earlier noble gas. Neon instead defines the [Ne] core used by Period 3 elements. For example, sodium is written [Ne] 3s¹, where [Ne] represents the filled 1s² 2s² 2p⁶ core.

How many valence electrons does neon have?

Neon has 8 valence electrons — the full complement of electrons in its outermost (n = 2) shell: 2 from 2s and 6 from 2p. A complete octet is what makes neon (and other noble gases) exceptionally stable and unreactive under normal conditions.

Why is neon chemically inert?

Neon's second electron shell is completely filled (2s² 2p⁶ = 8 electrons). There are no empty or half-filled valence orbitals to accept electrons from other atoms, and the filled shell is energetically very stable. Neon therefore has essentially zero tendency to form chemical bonds.

How does Hund's rule apply to neon?

Hund's rule says electrons occupy each degenerate orbital singly with parallel spins before pairing. The three 2p orbitals (ml = −1, 0, +1) are degenerate. Electrons 5, 6, and 7 each enter one 2p orbital with spin-up; electrons 8, 9, and 10 then pair in those orbitals with spin-down.

What is the effective nuclear charge (Zeff) experienced by neon's 2p electrons?

Using Slater's rules, the 2p electrons in neon experience a Zeff ≈ 5.85 (nuclear charge Z = 10, minus shielding of ~4.15 from the inner 1s² and 2s² electrons plus partial shielding from the other 2p electrons). This high Zeff relative to smaller atoms explains neon's high ionization energy.

Neon Electron Configuration

Explore neon's 1s² 2s² 2p⁶ electron configuration, orbital box diagram, all four quantum numbers for each electron, and key atomic properties in one interactive reference.

Shell Visualization (Bohr Model)

n=1, e⁻ (spin-up)

n=1, e⁻ (spin-down)

n=2, e⁻ (8 electrons)

2 electrons in shell n = 1 and 8 electrons in shell n = 2.

Electron Configuration

1s 2

2s 2

2p 6

Shell 1 electrons

Shell 2 electrons

Total electrons

Abbreviated: [Ne] — neon defines the noble-gas core used by Period 3 elements (e.g., Na = [Ne] 3s¹).

Orbital Box Diagram

n = 1 (2 electrons)

↑ ↓

n = 2 (8 electrons)

↑ ↓

2p (mₓ = −1, 0, +1)

All five orbitals are fully paired. Hund's rule placed one spin-up electron in each 2p orbital before pairing was complete.

Quantum Numbers — All 10 Electrons

e⁻	Orbital	n	l	mₓ	mₛ
1	1s	1	0	0	+½
2	1s	1	0	0	−½
3	2s	2	0	0	+½
4	2s	2	0	0	−½
5	2p	2	1	-1	+½
6	2p	2	1	0	+½
7	2p	2	1	+1	+½
8	2p	2	1	-1	−½
9	2p	2	1	0	−½
10	2p	2	1	+1	−½

Electrons 5–7 enter the three 2p orbitals singly (Hund's rule); electrons 8–10 pair them. No two electrons share all four quantum numbers (Pauli Exclusion Principle).

Key Atomic Properties

Atomic Number (Z) 10 10 protons, 10 electrons

Atomic Mass 20.180 atomic mass units (u)

1st Ionization Energy 21.565 eV (2081 kJ/mol) — highest in Period 2

Electron Affinity ≈ 0 Does not form stable negative ions

Electronegativity — Not defined (forms no bonds)

Van der Waals Radius 154 pm

Principles Applied

1
Aufbau Principle
Electrons fill orbitals in order of increasing energy: 1s → 2s → 2p. Neon's 10 electrons fill all three subshells in this order, completely filling both the n = 1 and n = 2 principal energy levels.
2
Pauli Exclusion Principle
No two electrons share all four quantum numbers. Each orbital holds at most two electrons, and they must have opposite spins (mₛ = +½ and −½). This limits the 1s, 2s, and each 2p orbital to exactly two electrons each.
3
Hund's Rule
Before any 2p orbital is doubly occupied, each of the three degenerate 2p orbitals (mₓ = −1, 0, +1) receives one spin-up electron. Electrons 5, 6, and 7 enter separately with parallel spins. Only then do electrons 8, 9, and 10 pair up, completing the 2p⁶ subshell.

Summary

Neon (Ne) is the tenth element on the periodic table and the second lightest noble gas, with an atomic number of 10. Its 10 electrons completely fill two principal energy levels: the 1s, 2s, and three 2p orbitals, giving a full configuration of 1s² 2s² 2p⁶. This completely filled second shell makes neon exceptionally stable and chemically inert. This tool shows an animated Bohr model with two electron shells, an orbital box diagram, a quantum number table for all ten electrons, and key atomic properties.

How it works

The page loads neon's fixed electron configuration (1s² 2s² 2p⁶) automatically — no input required.
The animated Bohr model shows two electrons in shell n = 1 and eight electrons in shell n = 2 orbiting the nucleus.
The orbital box diagram displays all five filled orbitals: 1s, 2s, 2p₋₁, 2p₀, and 2p₊₁.
The quantum number table lists n, l, mₗ, and mₛ for all ten electrons.
The properties panel shows atomic number, mass, ionization energies, and other key data.
The principles section explains how the Aufbau, Pauli, and Hund rules apply to neon.

Use cases

Verify neon's electron configuration quickly for chemistry homework or exams.
Study how Hund's rule fills the three 2p orbitals before pairing any electrons.
Use neon as the noble-gas core [Ne] abbreviation for Period 3 elements like sodium.
Understand why neon is chemically inert — both the n = 1 and n = 2 shells are completely full.
Compare neon's full-shell configuration with fluorine's one-electron-short 2p⁵.
Teach the concept of shielding: inner electrons reduce the effective nuclear charge on outer electrons.
Prepare for AP Chemistry, IB Chemistry, or university-level quantum mechanics coursework.
Review ionization energy trends — neon has the highest first ionization energy of Period 2.

Frequently Asked Questions

Last updated: 2026-09-30 · Reviewed by Nham Vu