Na
Sodium
Z = 11 · Alkali Metal · 23.0 u
Nuclear Engineering Significance
Primary coolant in sodium-cooled fast reactors (SFRs) such as EBR-II and BN-600. Good heat transfer properties but chemically reactive with air and water. Thermal absorption (σ_a = 0.53 b) is acceptable for fast-spectrum designs. Na-24 activation (t₁/₂ = 15 h) produces an intermediate heat exchanger requirement.
Basic properties
- Atomic number (Z)
- 11
- Standard atomic mass
- 23.0 u
- Category
- Alkali Metal
Isotopes & cross-section data
| Isotope | Mass (A) | Half-life | ZAID | Libraries |
|---|---|---|---|---|
| Na-23 | 23 | Stable | .80c.71c.70c |