Energetics of ionic salt transfer from water to an organic solvent

If a material is placed between the charges, the force is reduced by an amount that depends upon the relative permittivity of the material. The new Coulombic potential energy is given by equation 8.2 where is the relative permittivity of the material. Since it is a relative quantity, is dimensionless. 

3 Energetics of ionic salt transfer from water to an organic solvent 

where Atranaferi/ and AjjansferG refer to the transfer of the specified ion from water to the organic solvent. A positive value of AtransferG° indicates an unfavourable transfer, while a negative value corresponds to a favourable process. 

Fluoride ion in solvents with which it is not able to form hydrogen bonds is sometimes described as naked , but this term is misleading in DMF, it still has a Gibbs energy of solvation of about —400kJmol ( i60kJmol less negative than in water) and so is still very much less reactive than in the gas phase. 

The data in Table 9.2 show that the large, non-polar [Ph4As] and [BPh4] ions are more solvated in each organic 

You may need to refer to the first part of Section 10.6 before 

Why can EtOH form hydrogen bonds with chloride ion, whereas Et20 cannot  

In an analogous approach to that discussed in Section 7.9, we can make the assumption that very large ions such as [Pli4As] and [BPh4] have the same values of A,r .f G° and the same values of. By considering a series 

The data in Table 9.2 show that the large, non-polar [Pli4As] and [BPh4] ions are more solvated in each organic solvent than in water enthalpy and entropy effects both contribute in the same direction. Alkali metal ions exhibit no simple pattern of behaviour, although in each solvent, values of and A, ferG° are less positive 

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