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Sesquioxides characteristics

The affinity of selenium for oxygen is less than that of sulphur. The dioxide, SeQ2, is well defined. The trioxide, Se03, is much less stable than its sulphur analogue, and until recently all attempts to isolate it have been unsuccessful (see p. 331). Selenium sesquioxide, Se203, has not been definitely isolated.1 An oxide of composition Se304 has been described,2 but its existence needs confirmation. The existence of a lower oxide, SeO, postulated to explain the characteristic odour of selenium when vaporised in air, is improbable.3... [Pg.326]

In Chapter 6, K. Bunzl examines the kinetics of ion exchanger in heterogeneous systems in order to provide a better understanding of the behavior of natural ion exchangers in the soil (clay minerals, humic substances, sesquioxides). With film diffusion as the rate-controlling factor in these mixtures, several important characteristics become predictable. [Pg.454]

The id-MaOs and 5-M2Q3 stmctures are associated particularly with the 4f and 5f sesquioxides. When there is polymorphism the A, B, and C structures are characteristically those of high-, medium-, and low-temperature forms respectively. The structures of some 4f and 5f oxides are set out in Table 12.6. A striking feature of the /I-M2O3 structure, which has been confirmed by neutron diffraction, is the unusual 7-coordination of the nietal atoms (Fig. 12.7). In La203 the nearest oxygen neighbours of La are 3 at 2-38, 1 at 2-45, and 3 at 2-72 A. [Pg.452]

Table 4.10. Some lattice spacings characteristic of rhodium, ceria and rhodium sesquioxide phases. Table 4.10. Some lattice spacings characteristic of rhodium, ceria and rhodium sesquioxide phases.
Because of the inner nature of the 4f orbitals, the dififerenees of eleetron configuration between the lanthanoid elements are associated to eleetrons relatively well screened from the chemical surroundings by the outer (5s p ) shell. This implies weak crystal fields splitting effects [28], and a relatively small eovalent contribution to the bonding, particularly in the sesquioxides. Accordingly, the ionic model plays an important role in determining their chemistry [21]. Also related to these chemical characteristics, the lanthanoid compounds exhibit a rich variety of stmctures, often reflected in the occurrence of polymorphism phenomena. [Pg.11]

Vaporization characteristics of rare earth metals and rare earth sesquioxides. [Pg.241]

The formation of sesquioxides and dioxides for the actinides beyond Pu is more characteristic of the behavior of the lanthanides. The exceptional stability of the... [Pg.453]

Synonyms Arcenous Acid Arcenous Acid Anhydride Arcenous Oxide Arsenic Sesquioxide White Arsenic Chemical Formula As O, Iii) Observable Characteristics — Physical State (as normally shipped) Solid Color. White (5dor Like garlic none (iii) Riysical and Chemical Properties — Physical State at 15 "C and I atm. Solid Molecular Weight 197.8 Boiling Point at I... [Pg.430]


See other pages where Sesquioxides characteristics is mentioned: [Pg.145]    [Pg.12]    [Pg.120]    [Pg.540]    [Pg.647]    [Pg.678]    [Pg.597]    [Pg.164]    [Pg.15]    [Pg.258]    [Pg.262]    [Pg.269]    [Pg.270]    [Pg.256]    [Pg.106]    [Pg.109]    [Pg.947]    [Pg.948]    [Pg.430]    [Pg.525]    [Pg.566]    [Pg.108]    [Pg.102]    [Pg.43]    [Pg.351]    [Pg.389]    [Pg.406]   
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Sesquioxide

Sesquioxides

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