Electron Configuration Calculator
Determine the distribution of electrons in atomic orbitals for any element
Select an Element
Atomic Number:
6
Element:
Carbon
Symbol:
C
Common Elements
Electron Configuration
1s² 2s² 2p²
[He] 2s² 2p²
Orbital Filling Diagram
Step-by-Step Process
Aufbau Principle – Orbital Filling Order
Memory Aid:
1s → 2s → 2p → 3s → 3p → 4s → 3d → 4p → 5s → 4d → 5p → 6s → 4f → 5d → 6p → 7s → 5f → 6d → 7p
“Smart Physicists Can Find Gold Particles”
Electron Configuration Rules
- Aufbau Principle: Electrons fill orbitals from lowest to highest energy
- Pauli Exclusion Principle: Each orbital holds max 2 electrons with opposite spins
- Hund’s Rule: Electrons fill degenerate orbitals singly before pairing up
Orbital Capacities
- s orbitals: 1 orbital × 2 electrons = 2 electrons
- p orbitals: 3 orbitals × 2 electrons = 6 electrons
- d orbitals: 5 orbitals × 2 electrons = 10 electrons
- f orbitals: 7 orbitals × 2 electrons = 14 electrons
Notation Guide
- 1s²: Principal quantum number (1), orbital type (s), electron count (2)
- [He]: Noble gas core notation for 1s²
- ↑↓: Paired electrons in an orbital
- ↑ : Unpaired electron in an orbital
Common Electron Configurations
Hydrogen (H) – 1 electron
1s¹
Simplest configuration with one electron in 1s orbital
Carbon (C) – 6 electrons
1s² 2s² 2p²
Hund’s rule: two unpaired electrons in 2p orbitals
Neon (Ne) – 10 electrons
1s² 2s² 2p⁶
Noble gas with completely filled first and second shells
Copper (Cu) – 29 electrons
[Ar] 4s¹ 3d¹⁰
Exception: half-filled/filled d-subshell stability