The number of electrons in each energy level of an atom depends on the level's principal quantum number (n). Each level can hold a maximum number of electrons calculated by the formula: 2n².
Electron Capacity by Energy Level
Here's a table summarizing the electron capacity for the first four energy levels, based on the provided reference (Questions and Answers):
| Energy Level (Principal Quantum Number) | Shell Letter | Electron Capacity |
|---|---|---|
| 1 | K | 2 |
| 2 | L | 8 |
| 3 | M | 18 |
| 4 | N | 32 |
- Level 1 (n=1, K shell): Holds a maximum of 2 electrons.
- Level 2 (n=2, L shell): Holds a maximum of 8 electrons.
- Level 3 (n=3, M shell): Holds a maximum of 18 electrons.
- Level 4 (n=4, N shell): Holds a maximum of 32 electrons.
This pattern continues for higher energy levels, although these higher levels are rarely completely filled in most atoms. Remember that each orbital can hold a maximum of two electrons (Electron shell - Wikipedia, 5.12: Energy Level - Chemistry LibreTexts).
