Salt univalent

The relative toxicities of thallium compounds depend on their solubHities and valence states. Soluble univalent thallium compounds, eg, thaHous sulfate, acetate, and carbonate, are especiaHy toxic. They are rapidly and completely absorbed from the gastrointestinal tract, skin peritoneal cavity, and sites of subcutaneous and intramuscular injection. Tb allium is also rapidly absorbed from the mucous membranes of the respiratory tract, mouth, and lungs foHowing inhalation of soluble thallium salts. Insoluble compounds, eg, thaHous sulfide and iodide, are poorly absorbed by any route and are less toxic. 

Complex salts of thorium fluorides have been generated by interaction of ThF with fluoride salts of aLkaU or other univalent cations under molten salt conditions. The general forms of these complexes are [ThF ] [15891 -02-8] ThFJ [1730048-0] and [ThF ] [56141-64-1], where typical countercations are LC, Na", K", Cs", NH" 4, and N2H" 3. Additional information on thorium fluorides can be found in the Hterature (81). 

Membrane Efficiency The permselectivity of an ion-exchange membrane is the ratio of the transport of electric charge through the membrane by specific ions to the total transport of electrons. Membranes are not strictly semipermeable, for coions are not completely excluded, particularly at higher feed concentrations. For example, the Donnan eqmlibrium for a univalent salt in dilute solution is ... 

Despite the above similarities, many differences between the members of this triad are also to be noted. Reduction of a trivalent compound, which yields a divalent compound in the case of cobalt, rarely does so for the heavier elements where the metal, univalent compounds, or hydrido complexes are the more usual products. Rhodium forms the quite stable, yellow [Rh(H20)6] " ion when hydrous Rh203 is dissolved in mineral acid, and it occurs in the solid state in salts such as the perchlorate, sulfate and alums. [Ir(H20)6] + is less readily obtained but has been shown to occur in solutions of in cone HCIO4. 

Polysulfides have been prepared with many different types of cations, both monoatomic Hke alkah metal ions and polyatomic Hke ammonium or substituted ammonium or phosphonium ions. In this chapter only those salts will be discussed in detail which contain univalent main-group cations although a large number of transition metal polysulfido complexes have been prepared [7-9]. 

Stigter, D, Electrophoresis of Highly Charged Colloidal Cylinders in Univalent Salt Solutions. 2. Random Orientation in External Field and Application to Polyelectrolytes, Journal of Physical Chemistry 82, 1424, 1978. 

Stigter, D, Kinetic Charge of Colloidal Electrolytes from Conductance and Electrophoresis. Detergent Micelles, Poly(methacrylates), and DNA in Univalent Salt Solutions, Journal of Physical Chemistry 83, 1670, 1979. 

The retarding effect of electrolytes in the application of basic dyes to acrylic fibres increases with increasing concentration of salt up to a certain level. Increasing the concentration beyond this point has no further effect on exhaustion with certain univalent anions, whilst with multivalent types there is an increase in dye sorption (Figure 12.2)... 

NiS4C4(CF3)4] is very readily reduced to the univalent anion, whose salts are insoluble in n-pentane but moderately to extremely soluble in most other organic solvents including aromatic hydrocarbons and carbon tetrachloride. To avoid reduction, all solvents and apparatus must be dry. Benzene and n-pentane stored over molecular sieves have been found to be adequately dry for use in the above procedure. 

From Section 19-1, we learned that if the concentrations of the weak acid or base and its salt are 0.05 Mor greater, and the salt contains a univalent cation, then... 

The presence of salts of univalent and bivalent cations increases, by several-fold, the activity of pectinesterases from higher plants, which is minimal in the absence of salts.38,50,57,6, 63,64 66,69,7° The activating effect of salts on pectinesterases of microbial origin is not so great, an increase by 1.5- to 2-fold being reported.51 56,63 76-78,80 Table III shows the concentrations of sodium chloride and calcium chloride that caused the maximal activation of pectinesterases of plant and microbial origin. The mechanism of activation has not yet been satisfactorily explained. 

In haemin the iron is combined thus The two hydrogen atoms of the NH-groups of its porphyrin are replaced by two principal valencies of the metal which is also united in complex combination to the two other N-atoms (as in the complex nickel compound of dimethylglyoxime according to Tschugaev). Then the resulting complex cation combines with Cl or another univalent anion to form a salt. 

In a solution containing a crown ether (Cr) and a salt of a univalent cation (MX), the equilibria (1) can exist. Dlp and Z>C8lp are the dissociation constants... 

AHf cation (g), and AHf salt (c) are the respective heats of formation of gaseous cation, gaseous anion, and crystalline salt. Kapustinskii s formula for univalent salts is —... 

The different techniques which have been applied to determine transport in polymer electrolytes are listed in Table 6.1. For a fully dissociated salt all the techniques yield the same values of t (small differences may arise due to second order effects such as long range ion interactions or solvent movement which may influence the different techniques in different ways). In the case of associated electrolytes, any of the techniques within one of the three groups will respond similarly, but the values obtained from different groups will, in general, be different. Space does not permit a detailed discussion of each technique, this is available elsewhere (see Bruce and Vincent (1989) and the references cited therein). However, we will consider one technique from each group to illustrate the differences. A solid polymer electrolyte containing an associated uni-univalent salt is assumed. 

Symmetrical Salts. For salts in which anions and cations have the same valence, activities and related quantities are defined in exactly the same way as for uniunivalent electrolytes. For example, for MgS04, a finite limiting slope is obtained when the activity is plotted against the square of the molality ratio. Furthermore, equals m. Consequently, the treatment of symmetrical salts does not differ from that just described for uni-univalent electrolytes. 

Unsymmetrical Salts. As an example of unsymmetrical salts, let us consider a salt such as BaCl2, which dissociates into one cation and two anions. By analogy with the case of a uni-univalent electrolyte, we can define the ion activities by the expression... 

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