Ethers, carbonium ions from aliphatic

The acidity function will be on its best behavior in aqueous mineral acid solutions where ionization is essentially complete, although even here similar aniline-type indicators do not show exactly parallel changes of indicator ratio with acidity (336). Several other groups of neutral bases give plots of the logarithm of the indicator ratio (henceforth alluded to as log Q) vs. Ho with slopes very far from unity. In the cases of the aryl olefins (85) some azulenes (231) 1, 3, 5-tri-methoxybenzene (213) and some indole bases (185-187,357) protonation produces a carbonium ion which exhibits quite different activity coefficient behavior than that of bases such as anilines, ketones, or aromatic ethers. Other compounds for which deviations from unit slope have been reported are the amides (98) (a very serious case), some aliphatic ethers (12), and phenols (11). 

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