Abstract
Solvent effects on acid-base equilibria are naturally most marked when the solvent itself enters into the equilibrium, as is the case for the conventional definition of acid strength by means of the equilibrium A + SH ⇌ B + SH +2 (where SH is the solvent). The existence of such an equilibrium implies that the solvent has some basic properties. Similarly, the occurrence of the reaction B + SH ⇌ A + S− (where S− is the anion derived by abstracting a proton from the solvent) implies that the solvent is acidic. The most important factor determining qualitative behaviour in a wide range of solvents is the acidic or basic nature of the solvent, as determined by its chemical nature. In a preliminary classification we can neglect other factors, notably the effect of dielectric constant on the association of ions or the forces between them.
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References
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Bell, R.P. (1973). The Effect of the Solvent on Protolytic Equilibria. In: The Proton in Chemistry. Springer, Boston, MA. https://doi.org/10.1007/978-1-4757-1592-7_4
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