- Sublimation temperature: 56.5 degrees C
- Melting point: 64.1 degrees C
- Molecular mass (UF₆): 349 amu
- Molecular mass (UF₆): 352 amu
- Appearance at room temperature: White crystalline solid
- State above 56 degrees C: Gas
Hazards of UF₆:
- Toxic — both uranium and fluorine compounds are toxic
- Highly corrosive to most metals
- Extremely reactive with water — reacts to form uranyl fluoride (UO₂F₂) and hydrofluoric acid (HF), which is extremely dangerous
- Low specific radioactivity means that chemical hazards far outweigh the radiological hazard
Safety Note: At low enrichments (less than 3% U-235), criticality is not possible without a moderator. Moisture ingress must be rigorously prevented, but large containers (up to 2.5 tonnes) can be used. At high enrichments, strict process controls to prevent criticality must be exercised.