Hydrogen fluoride acid-base behaviour

Thus nitric acid behaves as a base in hydrogen fluoride. Hence increases of conductivity when substances dissolve in hydrogen fluoride may be due to acidic or basic behaviour. 

The two components of ammonium fluoride behave in very much the same way as do donor and acceptor impurities in electronic semiconductors, leading to more or less complete compensation. This behaviour is illustrated, as far as static conductivity is concerned, by the careful study of Levi et al. (1963) in which the ratio of hydrogen fluoride to ammonia concentrations was varied over a wide range. The experimental results are shown in fig. 9.9 and illustrate the expected behaviour. This can be calculated by the normal chemical methods used for a solution containing a weak acid and a weak base but, to obtain reasonable agreement with experi-... 

Basic behaviour of hydrogen fluoride in fluorosulphuric acid has been concluded from the results of electrolysis experiments nd of conductometric studies . Arsenic(III) fluoride and antimony(III) fluoride are weak bases ... 

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