The D0 acidity function in deuterium sulphate solutions at 25 °C

Abstract

The D₀ scale for D₂SO₄–D₂O solutions is extended, with a special technique in which additions are made to the same spectrophotometric cell to increase the precision of the measurements, and pK_BD+ values are recorded for the Jorgenson and Harrter series of nitroaniline bases. Though D₀ is slightly more negative than the corresponding H₀ up to over 90%(w/w) of the acid when the comparison is made on a simple %(w/w) basis, the scales become virtually identical up to 90% when allowance is made for the different molecular weights. Small differences do however appear in the 90–100% region.