الفهرس 
acknowledgmentOnly 14 pages are availabe for public view
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Abstract
Effect of Ion Association on the Rate of Chemical Reactions
Inspite of the successes of the Bronsted theory of the primary salt effect, numerous apparent anomalies are known and added salts often exhibit specific effects which reflect real limitation in the theory. In many cases, however the anomalies arise in conditions where ion-pairing is to be expected in the reaction mixture.
Monk et al(1) have found significant rate deceleration in the base hydrolysis of cobaltpentammine halides, and have analysed the results in terms of ion-pairs which were deactivated due to a reduced electrostatic charge (c.f.
analysis of Jones and Fhilips (2)). Similarly, the accelera- tion by added anions in the acid hydrolysis of Cr(NH)]
(3-5). Fosey and Taube (6)
2+
where there should be no ionic strength effect, has been taken as evidence of ion pairing have shown, by means of spectrophotometry that the reaction
[Co(NH3)5804] + H2O
.
[Co(NH3)20]
3+
2
+
proceeded predominantly through the ion-pair Co (NH3)520, So Increasing sulphation caused an increase in both forward and reverse reactions. They concluded that the chemical nature of the ion-pairing ligand was not of prime importance and did not directly influence the mechanism of the rate determining step.