Equilibrium hydrolysis

Table 3. Hydrolysis, Equilibrium, and Complex Formation Constants...

Successive introduction of two methyl groups at ring carbon increases the hydrolysis rate by a factor of 10 in each step, indicating cation formation in the transition state as in acetal hydrolysis. Equilibrium protonation before hydrolysis becomes evident from an increasing rate of hydrolysis with a decreasing pH value (Table 3). Below pH 3 no further increase of rate is observed, so that protonation is assumed to be complete. 

Through all these calculations of the effect of pH and metal ions on the ATP hydrolysis equilibrium, we have assumed standard conditions with respect to concentrations of all species except for protons. The levels of ATP, ADP, and other high-energy metabolites never even begin to approach the standard state of 1 M. In most cells, the concentrations of these species are more typically 1 to 5 mM or even less. Earlier, we described the effect of concentration on equilibrium constants and free energies in the form of Equation (3.12). For the present case, we can rewrite this as... 

The plasma chemical decomposition method is based on rapid heating, decomposition and hydrolysis of fluoride compounds to obtain powdered oxides following interaction with water. Rakov and Teslenko [533] showed that the following hydrolysis equilibrium... 

A common characteristic to all the chemical reactions involved in step polymerisation that should be emphasised is that they are most often equilibrated reactions. For instance, the polyesterification reaction is based on the esterification/hydrolysis equilibrium... 

Chromium(II) chloride, 6 528t, 531, 564t Chromium(III) chloride, 6 532 physical properties, 6 528t Chromium(IV) chloride, 6 535 Chromium(III) chloride hexahydrate, physical properties, 6 528t Chromium chromate coatings, 76 219—220 Chromium complexes, 9 399 Chromium compounds, 6 526-571 analytical methods, 6 547-548 economic aspects, 6 543-546 environmental concerns, 6 550—551 health and safety factors, 6 548-550 hydrolysis, equilibrium, and complex formation constants, 6 530t manufacture, 6 538-543... 

For cis-diarnmmedichloroplatinum(Il) to work according to the proposed mechanism. it must hydrolyze In the right place t it hydrolyzes in the blood before it gets to the chromosomes within the cell, it will be more likely to react with a nonlurget species. Fortunately for the stability of the complex, the blood is approximately 0.1 M in chloride ion, forcing the hydrolysis equilibrium (Echloro complex. Once the drug crosses the cell membrane into the cytoplasm, it finds a... 

Because only a salt is present in solution, the problem involves the hydrolysis equilibrium... 

Salt of a weak acid and a strong base (see p 359). This is a hydrolysis equilibrium reaction ... 

Hydrolysis. Complexes formed by Pu ions with OH- represent hydrolysis reactions. There is extensive interaction between Pux+ and water. Pu(III) hydrolyzes at ca pH 7 (105) the first hydrolysis equilibrium is as follows ... 

Hydrolysis is very extensive in Pu(IV) solutions, less so in Pu(III) and Pu(VI), and least in Pu(V). The chemical properties of Pu(IV) are somewhat similar to those of Ce(IV) and U(TV) (see Ceriumand cerium compounds). The hydrolysis thermodynamics of Pu(TV) have been assessed in perchlorate solutions (105). The first hydrolysis equilibrium is... 

Dissolved carbon dioxide is different from species like S03 and NH3 in aqueous solutions in that the hydration reaction is slow enough (r, /2 = 15 seconds at pH 7 and 298 K) so that the rate constants involved can be determined and can be used to calculate the hydrolysis equilibrium constant (Edsall, 1969) at 298.15 K in terms of species for... 

Base-mediated ester hydrolyses have a high driving force. This is because of the acid/base reaction between the carboxylic acid formed in the reaction, and the base used as the reagent. The resonance stabilization of the carboxylate is approximately 30 kcal/mol, which means a gain of about 16 kcal/mol compared to the starting material, the carboxylic ester (resonance stabilization 14 kcal/mol according to Table 6.1). Accordingly, the hydrolysis equilibrium lies completely on the side of the carboxylate. 

Thus, the hydrogen ions, formed from the dissociation of water, will partly combine with acetate ions. The two equations can therefore be added, which results in the overall hydrolysis equilibrium ... 

The degree of hydrolysis can be defined as the fraction of each mole of the anion hydrolysed in the equilibrium. If c is the total concentration of the anion (i.e. of the salt) and x is the degree of hydrolysis, the actual concentrations of the species involved in the hydrolysis equilibrium are as follows ... 

In general, equations (i) and (ii) can be added, when the overall hydrolysis equilibrium can be expressed as... 

A well-washed suspension of the precipitate shows a slight alkaline reaction owing to the hydrolysis equilibrium ... 

Determined by direct UV-vis spectroscopic observation of the hydrolysis equilibrium in 50% aq MeCN. 

This reaction is much faster than the hydrolysis and lowers the HOCl concentration so that the hydrolysis equilibrium is shifted to the HOCl side. Excess HNCI2 then reacts with the formed trichloramine to form decomposition products. 

Eqnilibrinm constant for dissolution of gaseous chlorine into water Hydrolysis equilibrium constant for Cl2(g)... 

Baes and Mesmer (1976) provide a critical evaluation of the extensive information on the identity of metal-ion species and their hydrolysis products in solutions, as well as the solid oxides and hydroxides they produce. They provide a critical compilation of hydrolysis equilibrium and oxide and hydroxide solubility constants. 

Hydrolysis equilibria can be interpreted in a meaningful way if the solutions are not oversaturated with respect to the solid hydroxide or oxide. Occasionally, it is desirable to extend equilibrium calculations into the region of oversaturation but quantitative interpretations for the species distribution must not be made unless metastable supersaturation can be demonstrated to exist. Most hydrolysis equilibrium constants have been determined in the presence of a swamping inert electrolyte of constant ionic strength (/ = 0.1, 1, or 3 M). As we have seen before, the formation of hydroxo species can be formulated in terms of acid-base equilibria. The formulation of equilibria of hydrolysis reactions is in agreement with that generally used for complex formation equilibria (see Table 6.2). 

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