The protonation of weak bases. A study of the protonation of some nitroaniline indicators and the determination of the H 0 values of aqueous sulphuric acid

Abstract

The protonation of some nitroaniline indicators has been studied in aqueous sulphuric acid over the temperature range 15–55°. The log l values of these indicators decrease with increasing temperature and the pK_BH⁺ values vary linearly with temperature. These log l and pK_BH⁺ values have also been used to calculate the Hammett acidity function (H₀) of the acid media over the temperature range 15–55°.