Exchange reactions chemical reactivity

The generalization was based on the introduction of the concept of donor-acceptor pairs into the theory of acids and bases this is a fundamental concept in the general interpretation of chemical reactivity. In the same way as a redox reaction depends on the exchange of electrons between the two species forming the redox system, reactions in an acid-base system also depend on the exchange of a chemically simple species—hydrogen cations, i.e. protons. Such a reaction is thus termed proto lytic. This approach leads to the following definitions ... 

B.l.a. Water eocchange rates. Water-exchange rates are key guides of chemical reactivity in aqueous coordination compounds. Aqueous metal-ligand complexation reactions take place through the diffusion-limited formation of an electrostatic ion pair,... 

Dyrkacz and his coworkers have recently described a new procedure for the separation of coals into macerals (14). The macerals can be obtained in pure form, but only in limited quantity. Inasmuch as many of the methods used for the study of coal require relatively large amounts of material, we have undertaken new work on the development of small scale reactions for the accurate determination of the differences in chemical reactivity of macerals. The hydrogen transfer reactions are discussed in this report. Preliminary work revealed that very reproducible results could be obtained when 25 mg of a representative maceral was used as a catalyst for the hydrogen exchange reaction between tetra-... 

Table 2.5 also lists some of the chemical reactions which can promote release of metal ions from these phases. Distribution patterns are also often described in terms of mode of bonding (e.g. ion exchangeable, weakly sorbed, chemi-sorbed, complexed). Evaluation of the amount bound by these different bonding modes, or associated with different phases can be achieved by treating samples of the solid with chemical solutions having a range of chemical reactivities. (Some of the alternative approaches utilised are summarised in Table 2.6.)... 

The chemical reactivity of 2,2 -bipyridyl anion-radicals has recently attracted attention in a comparative study, again with 1,10-phenanthroline, the rates of exchange of ring protons for D at 100° were determined and related to their catalysis of equilibration of H2-D2.114 Others have made a mechanistic study of the same reaction.115... 

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