Nitrogen SPDF Electron Configuration Explained
Nitrogen has atomic number 7, meaning it has 7 electrons to arrange across its orbitals. Its ground-state electron configuration is:
Full notation: `1s² 2s² 2p³`
Shorthand notation: `[He] 2s² 2p³`
This configuration places Nitrogen in the P-block of the periodic table — Period 2, Group 15. The last subshell filled (the p subshell) determines its block.
SPDF notation tells you exactly: which subshell each electron occupies, how many electrons are in it, and the energy level of each group. This is far more detail than the simpler Bohr model, which only shows shell totals.
Aufbau Filling Sequence for Nitrogen
The Aufbau (building-up) principle states electrons fill the lowest available energy subshell first. For Nitrogen (Z=7), the filling stops at the 2p³ subshell.
Standard Aufbau sequence:
1s → 2s → 2p → 3s → 3p → 4s → 3d → 4p → 5s → 4d → 5p → 6s → 4f → 5d → 6p → 7s → 5f → 6d → 7p
After filling, Nitrogen's configuration ends at 1s² 2s² 2p³, with 5 valence electrons in its outermost subshell.
Orbital Diagram of Nitrogen (s, p, d, f)
The orbital diagram of Nitrogen expands the configuration 1s² 2s² 2p³ into individual orbital boxes:
- Each s subshell holds max 2 electrons (1 orbital)
- Each p subshell holds max 6 electrons (3 orbitals)
- Each d subshell holds max 10 electrons (5 orbitals)
- Each f subshell holds max 14 electrons (7 orbitals)
Hund's Rule dictates that within any subshell, electrons fill each orbital singly (spin up ↑) before pairing. This avoids electron–electron repulsion. Nitrogen's P-block placement confirms its last orbitals are p type.
The interactive diagram above shows Nitrogen's complete subshell breakdown with orbital boxes for every energy level.
How to Write Nitrogen's Electron Configuration
Follow these steps to write Nitrogen's electron configuration from scratch:
Step 1: Identify the atomic number: Z = 7 — this is the total number of electrons to place.
Step 2: Follow the Aufbau sequence, filling the lowest energy subshells first:
> 1s → 2s → 2p → 3s → 3p → 4s → 3d → 4p → ...
Step 3: Apply Hund's Rule inside each subshell — one electron per orbital before pairing begins.
Step 4: Apply the Pauli Exclusion Principle — each orbital holds at most 2 electrons with opposite spins.
Step 5: After filling all 7 electrons, your result should match:
> 1s² 2s² 2p³
Shorthand: Replace the preceding noble gas core with its symbol:
> [He] 2s² 2p³
Why Nitrogen Matters (Real-World Insight)
🔬 Element Comparison
Nitrogen vs Oxygen — Key Differences
Although Nitrogen (Z=7) and Oxygen (Z=8) are adjacent on the periodic table, they behave very differently. Nitrogen has 5 valence electrons vs Oxygen's 6. Their electronegativity gap is 0.40 — a critical factor in predicting bond polarity when the two interact.
Valence Electrons & P-Block Position
Nitrogen has 5 valence electrons — the electrons in its highest occupied principal energy level.
As a P-block element, Nitrogen's valence electrons reside in p orbitals. These are the only electrons involved in chemical bonding.
| Block | Type | Max Valence e⁻ |
|---|---|---|
| s-block | Groups 1–2 | 1–2 |
| p-block | Groups 13–18 | 3–8 |
| d-block | Groups 3–12 | up to 10 |
| f-block | Lanthanides/Actinides | up to 14 |
Nitrogen sits in this table as a p-block element with 5 valence electrons.
→ See Nitrogen's valence electrons in the Bohr model for the shell-based view.
→ Electronegativity of Nitrogen — how strongly it attracts these electrons.
Frequently Asked Questions
Q. How many electrons does Nitrogen have?
Nitrogen has 7 electrons, matching its atomic number. In a neutral atom, these are balanced by 7 protons in the nucleus.
Q. What is the shell structure of Nitrogen?
The electron shell distribution for Nitrogen is 2, 5. This shows how all 7 electrons are arranged across 2 principal energy levels.
Q. How many valence electrons does Nitrogen have?
Nitrogen has 5 valence electrons in its outermost shell. These are responsible for its chemical bonding and placement in Group 15.
Q. What is the SPDF configuration of Nitrogen?
The full configuration is 1s² 2s² 2p³. This describes the exact subshell occupancy following the Aufbau principle.
Q. What block is Nitrogen in?
Nitrogen is in the P-block because its highest-energy electrons occupy p orbitals.

