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Lux-Flood acid

In the above reactions both MgO and CaO are the oxide ion donor and hence act as bases, whereas Si02 and S03 are the oxide-ion acceptor and hence act as acids. Ultimately, the Lux-Flood acid and base react to form magnesium silicate (MgSi03) and calcium sulphate (CaS04) salts respectively. [Pg.98]

Lux-Flood acid-base properties of dissolved oxides. [Pg.411]

In silicate melts and other nonprotonated solvents, the Bronsted-Lowry equation is not applicable and is conveniently replaced by the Lux-Flood acid-base definition (Lux, 1939 Flood and Forland, 1947), according to which free oxygen 0 replaces A basic oxide is one capable of furnishing oxygen ions, and an acidic oxide is one that associates oxygen ions ... [Pg.418]

As described in chapter 6, the main factors determining the solubility of a given element in a silicate melt are the Lux-Flood acidity of its oxide and the relative proportions of the cations of different field strengths (cation charge over squared sum of cation plus ligand radii ZIA ) or charge densities (cation charge over ionic radius Z/r). [Pg.674]

In these melts, the concept of acidity of Lux-Flood [343] (L-F) is applied. A Lux-Flood acid is defined as an oxide ion acceptor leading to the formation of the conjugate base ... [Pg.547]

In oxide melts the solvent system corresponds to the Lux-Flood acid/base... [Pg.157]

Lux-Flood acidities of oxides are important in reactions taking place in silicate melts, for example in glass manufacture. The values correlate well with other aspects of acid-base behaviour, for example that manifested in aqueous chemistry (see Topics B2 and F7). Acidity of EO generally... [Pg.158]

Since the process of complexation between the melt anion and different cations of close radii proceeds to practically equal degrees, one may assume that for a set of oxides dissolved in the same ionic solvent the solubility value should be dependent on the degree of acidic cation-anion interaction which is the Lux-Flood acid-base equilibrium. In this case, the constant of the... [Pg.229]

Ionic melts as media for Lux-Flood acid-base reactions may be divided into two types on the base of constitutional (i.e., being a part of main components of the melt) oxygen ions oxygen-less and oxygen-containing ones. Let us consider some features of acid-base interactions in the mentioned melts. ... [Pg.618]

Stability range of most melts, including chlorides. This occurs in nitrates themselves, of course, as a limiting reaction (but see below). Such electrochemical behavior might be rationalized in terms of the Lux-Flood acid-base formalization for many years the reduction of nitrate ions was written ... [Pg.614]

Apart from nitrate ions, the direct reduction of carbonate, phosphate, and silicate anions have all been reported. Some controversy surrounds the electroreduction of sulfate ions water may be implicated in this process. Inman and Wrench could only induce cathodic electroactivity of sulfate ions dissolved in a chloride melt by release of SO3, the conjugate acid, with a stronger Lux-Flood acid, metaphosphate, P03. While the alkali metal and alkaline earth sulfates, carbonates, and nitrates are clearly ionic, borate, phosphate, and silicate melts are highly polymerized. In such systems, the mobile cations move freely about the anion lattice network, which comprises a temperature- and compositional-dependent equilibrium between ion fragments of variable chain length. Inman and Franks observed kinetically limited electroreduction processes in a phosphate melt, as might be expected if only the smallest fragments of the dynamic polymer equilibrium are electroactive. [Pg.614]

In non-protonic solvents like molten oxides and silicates, such a definition is clearly unsuitable, and in the case of molten oxides or oxy-acids the Lux-Flood acid-base definition is frequently used. In this, oxide-ion, 02, takes the place of protons in the Bronsted-Lowry scheme. Thus, a basic oxide is a substance capable of fiurnishing pxide ions, and an acidic oxide is one which reacts with 02 ... [Pg.306]

The constituent components of these melts are not susceptible to Lux-Flood acid-base dissociation, therefore, there are no acid in solvent, whereas the solvent base is adduct of oxide ions to constituent cations of the melt. [Pg.518]

The higher the degree of interaction the more complete the oxide ion fixation in complexes that shifts Lux-Flood acid-base reactions to the side corresponding to destruction of the basic products. This can be found out experimentally by changing the calculated values of equilibrium constants of the acid-base reactions in a given ionic solvent as compared to the corresponding value in the reference (standard) melt. The results concerning the information on the relative acidic properties of ionic solvents will be considered below. [Pg.519]

HOMOGENEOUS ACID-BASE REACTIONS IN MOLTEN SALTS 9.2.3.1 Methods of estimations of Lux-Flood acidity in molten salts... [Pg.533]

See other pages where Lux-Flood acid is mentioned: [Pg.228]    [Pg.231]    [Pg.172]    [Pg.172]    [Pg.536]    [Pg.172]    [Pg.172]    [Pg.172]    [Pg.172]    [Pg.525]    [Pg.5]    [Pg.11]    [Pg.320]    [Pg.320]    [Pg.618]    [Pg.619]    [Pg.619]    [Pg.273]    [Pg.222]    [Pg.320]    [Pg.320]    [Pg.455]    [Pg.89]    [Pg.90]    [Pg.508]    [Pg.509]    [Pg.513]    [Pg.515]    [Pg.525]    [Pg.535]    [Pg.537]   
See also in sourсe #XX -- [ Pg.550 ]



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