Oxoacidic acid-base pair

As the solvents of the first kind, ojqrgen-containing ionic melts, involve not only oxide ions bnt also the solvent acid as a product of the intrinsic acid-base dissociation. This reason leads to the two-side hmitation of acid-base ranges that gives rise to different specific featnres of these solvents, such as the levehng of properties of acids, narrowing of acid-base range with temperatme rise, etc. The behavior of the oxoacidic acid-base pairs in these solvents is similar to that of the Bronsted-Lowry acid-base pairs in aqueous solutions. 

Fig. 1.1.3. The general oxoacidity scale of ionic melts. The positions of the conjugated acid-base pair corresponds to the KCl-NaCl eutectic at 700 °C.

To demonstrate the possibilities of the discussed variants of oxoacidity determination, let us consider the corresponding results obtained in Li -based chloride melts. The method for HCI/H2O acid-base pair yields for KCl-LiCl eutectic value of Q (pl ) ca. 8, whereas the solubility method gives value of and the use of Cr207/CrO acid-base pair permits to estimate plKci-Lici 3.6. It is interesting that the oxobasicity index of 2CsCl-LiCl melt is found in the mentioned above paper to be ca 3.8. The presented comparison shows that the use of HCI/H2O leads to overestimation of oxoacidic properties of the chloride melts whereas the results of other approaches are practically coincident. 

Although oxoacids and hydroxides are Arrhenius acids and bases (they release or OYi (aq) into aqueous solution), acid and base anhydrides do not fall into this classification because they contain neither nor OH. Acid anhydrides are acids in the Lewis sense, (they accept electron pairs), and base anhydrides are bases in the Lewis sense, (their ions donate electron pairs). The reaction between an acid anhydride and a base anhydride is then a Lewis acid-base reaction. An example of such a reaction is... 

In Chapter 9 we established the first five components of our interconnected network of ideas for understanding the periodic table. These included the periodic law, the uniqueness principle, the diagonal effect, the inert-pair effect, and the metal-nonmetal line. These components are summarized individually and collectively in colored figures located on the front inside cover of the book The icons for each component are shown there as well as on the bookmark pullout in the back of the text. In Chapter 10 we discussed hydrogen and the hydrides (as well as basic nuclear processes). In Chapter 11 we discussed the chemistry of oxygen, reviewed and extended our knowledge of the nature of water and aqueous solutions, and added a sixth component to our network the acid-base character of oxides and their corresponding hydroxides and oxoacids. The network with this additional component is shown in color on the top left side of the back inside cover of the book. 

Many halides and oxides are Lewis acids compounds with lone-pairs are Lewis bases. Bronsted acidity is possible in hydrides and oxoacids. Halide complexes can also be formed by ion transfer. 

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