Title: Uranium Hexafluoride
CAS Registry Number: 7783-81-5
Molecular Formula: F6U
Molecular Weight: 352.02
Percent Composition: F 32.38%, U 67.62%
Line Formula: UF6
Literature References: Prepd by the action of fluorine on uranium metal or carbide; on uranium pentachloride; on uranium tetrafluoride; on triuranium octaoxide in the presence of carbon. It appears that all uranium compds when heated with fluorine to a sufficiently high temp give UF6: National Nuclear Energy Series VIII-5, J. J. Katz, E. Rabinowitch, The Chemistry of Uranium, part I (New York, 1951) pp 396-449.
Properties: Volatile, white monoclinic cryst solid. d420.7 5.09. d70 (liq) 3.595. mp 64.8°. Sublimes at 56.5°. Critical temp 230.2°, crit pressure 45.5 atm: Oliver et al., J. Am. Chem. Soc. 75, 2827 (1953). Reacts vigorously with water, forming mainly UO2F2 and HF. Sol in liq chlorine and bromine. Dissolves in nitrobenzene to give a dark red soln fuming in air. Sol in carbon tetrachloride, chloroform, and sym-tetrachloroethane, Cl2CHCHCl2, which forms the most stable soln, extensive reaction occurring only after several days at room temp. Sol in fluorocarbons (C6F12 or C7F16) without reaction. Best handled in copper apparatus.
Melting point: mp 64.8°
Density: d420.7 5.09; d70 (liq) 3.595 |