Shells & Subshells

Quantum numbers and Pauli

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Electrons have quantum numbers n, ℓ, mℓ and spin.
• Pauli exclusion: at most 2 electrons per orbital.
• Subshells hold 2 (s), 6 (p), 10 (d), 14 (f); shell $n$ holds $2n^2$.

Steps

1. An address for each electron
2. Shell capacity
3. Orbital shapes
4. Counting orbitals
5. Hund’s rule
6. Without Pauli