| Proton | Neutron | Nuclear Spin | Energy State | |
|---|---|---|---|---|
| 30Ar | 18 | 12 | 0 | |
| 31Ar | 18 | 13 | 5/2 | |
| 32Ar | 18 | 14 | 0 | |
| 33Ar | 18 | 15 | 1/2 | |
| 34Ar | 18 | 16 | 0 | |
| 35Ar | 18 | 17 | 3/2 | |
| 36Ar | 18 | 18 | 0 | Stable |
| 37Ar | 18 | 19 | 3/2 | |
| 38Ar | 18 | 20 | 0 | Stable |
| 39Ar | 18 | 21 | -7/2 | |
| 40Ar | 18 | 22 | 0 | Stable |
| 41Ar | 18 | 23 | -7/2 | |
| 42Ar | 18 | 24 | 0 | |
| 43Ar | 18 | 25 | -5/2 | |
| 44Ar | 18 | 26 | 0 | |
| 45Ar | 18 | 27 | -5/2 | |
| 46Ar | 18 | 28 | 0 | |
| 47Ar | 18 | 29 | -3/2 | |
| 48Ar | 18 | 30 | 0 | |
| 49Ar | 18 | 31 | -3/2 | |
| 50Ar | 18 | 32 | 0 | |
| 51Ar | 18 | 33 | -3/2 | |
| 52Ar | 18 | 34 | 0 | |
| 53Ar | 18 | 35 | -5/2 |