| Quantity | Value | Units | Value | Units |
| Atomic number | 12 | |||
| Atomic mass | 24.3050(6) | g mole-1 | ||
| Density | 1.74 | g cm-3 | ||
| Minimum ionization | 1.674 | MeV g-1cm2 | 2.913 | MeV cm-1 |
| Nuclear collision length | 68.2 | g cm-2 | 39.20 | cm |
| Nuclear interaction length | 104.1 | g cm-2 | 59.84 | cm |
| Pion collision length | 94.2 | g cm-2 | 54.13 | cm |
| Pion interaction length | 133.7 | g cm-2 | 76.81 | cm |
| Radiation length | 25.03 | g cm-2 | 14.39 | cm |
| Critical energy | 46.55 | MeV (for e-) | 45.25 | MeV (for e+) |
| Molière radius | 11.40 | g cm-2 | 6.553 | cm |
Plasma energy ![]() |
26.71 | eV | ||
| Muon critical energy | 659. | GeV |