General acid-base theory and non-aqueous solvents

8 General acid-base theory and non-aqueous solvents The general relationship, 

There are four types of solvent which may be distinguished in terms of acid-base theory  

In autoprotic reactions the term lyonium ion is often given to the ion species resulting from proton solvation (e.g. HsO , NH4 ) while the solvent residue (less the proton) is called the lyate ion (e.g. CaHsO , NH2 ). 

The proton affinities of the solvent and its lyate ion decide the acid-base characteristics of a particular solute in that solvent. Thus, if a solute has a greater proton affinity than that of the lyate ion deriving from the solvent, it will behave as a base in that solvent. On the other hand, if the conjugate base to a solute has a smaller proton affinity than the solvent itself, the solute behaves as an acid. 

the conjugate base of benzoic acid, C HsCOO , has less affinity for protons than water so that the reaction 

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