Hexafluoride physical properties

Molybdenum hexafluoride [7783-77-9] MoF, is a volatile liquid at room temperature. It is very moisture sensitive, hydrolysing immediately upon contact with water to produce HF and molybdenum oxyfluorides. MoF should therefore be handled in a closed system or in a vacuum line located in a chemical hood. The crystals possess a body-centered cubic stmcture that changes to orthorhombic below —96° C (1,2). The known physical properties are Hsted in Table 1. 

Molybdenum hexafluoride. 3,1412 Molybdenum-iron-sulfur complexes, 4,241 Molybdenum oxide amino acid formation prebiotic systems, 6, 872 Molybdenum storage protein microorganisms, 6, 681 Molybdenum telluride, 3, 1431 Molybdenum tetraalkoxides physical properties, 2, 347 Molybdenum tribromide, 3,1330 Molybdenum trichloride, 3,1330 Molybdenum trifluoride, 3, 1330 Molybdenum trihalides, 3, 1330 bond lengths, 3, 1330 magnetic moments, 3,1330 preparation, 3,1330 properties, 3, 1330 structure, 3,1330 Molybdenum triiodide, 3,1330 Molybdenum trioxide complexes, 3, 1379 Molybdenum triselenide, 3, 143)... 

Chemical and physical properties of the hexafluorides recently have been reviewed by Weinstock (321), who also accounted for the structures of these volatile compounds in the solid state. The vibrational properties of hexafluoride molecules have been summarized by Weinstock and Gooiman (325). 

The physical properties of tungsten hexafluoride are given in Table 5 [54-57], Tungsten hexafluoride is a colorless gas at room temperature and is ten times as heavy as air. It condenses into a pale yellow liquid at 17.5 C and forms a white solid below 2.3°C [54]. The vapor pressure is given by the following equations [56] ... 

Physical properties of sulfur hexafluoride are listed in Table I. These include various values of the critical constants. Several excellent studies of the critical phenomena have been made to learn whether the predictions of Harrison and Mayer (125) are correct. They suggested in 1938 that there could be a range of temperature above the observed critical point (disappearance of meniscus) in which the slope of pressure versus volume isotherms is zero. Their arguments have been criticized by Zimin (334) in... 

Concurrent with the injection of iron is the injection of the inert chemical tracer sulfur hexafluoride (SFg). By presaturating a tank of sea water with SFg and employing an expandable displacement bladder, a constant molar injection ratio of Fe SFg can be achieved (Figure 6). In this way, both conservative and nonconservative removal of iron can be quantified. Sulfur hexafluoride traces the physical properties of the enriched patch the relatively rapid shipboard detection of SFg can be used to track and... 

The transuranium elements such as neptunium, plutonium or americium form hexafluoride compounds at their highest valency state with physical properties close to those of UF6 but these compounds are not stable when the fluorine partial pressme decreases. Under such conditions they are converted into a lower valency state and remain as a soUd product. This means that the main fraction of these impurities can be collected as ash or dust if there is still a small proportion remaining in the liquid UFe, it can be removed by a special filter before the container is filled. The specified upper limit for residual transuranium activity in the reprocessed uranium amounts to 2.5Bq/gU, with Pu, Pu and Np as the guide isotopes. 

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