Acid-base chemistry of non aqueous solvents: glacial acetic acid
Abstract
Chemistry in non-aqueous solvents often helps the qualitative and quantitative analysis of chemical species which are simply not accessible in aqueous media. To date, empirical knowledge has established some general rules regarding the application of these solvents in the industry, while there is poor scientific knowledge about the physicochemical processes related with this type of media. In this paper we describe the principles of acid-base chemistry when glacial acetic acid is used as solvent. Since this is an acidic solvent, it is capable of leveling bases so they would present a strong behavior while in water the same bases would be too weak for analysis. Being a low polarity solvent, solutes present an ion-pair formation process which precedes the ionization, which is less favored. Considering the above, the physicochemical interpretation for base reactions with acids (such as perchloric), both dissolved in glacial acetic acid, has very different scope that the one commonly used in aqueous media.
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References
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