Protogenic solvents, acid-base reactions

Returning now to the bulk solvents, their relevant acid-base reaction is their autoprotolysis, if protic or protogenic, according to ... 

This reaction occurs because the acid possesses some protophilic properties, and these become manifest in the presence of the very strongly protogenic solvent. As may be expected, the stronger the acid is in water, the weaker does it behave as a base in hydrogen fluoride. 

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