Abstract
The determination of some weak bases at low concentrations was investigated photometrically in non-aqueous solvents. To ensure accuracy, the chemical stoichiometric relationship between color transition of the indicator and the equivalence point was considered. The color transition of the indicator was calculated by complementary tristimulus colorimetry, which is preferable to ordinary colorimetry when dealing with several species in solution. Theoretical titration curves of titration ratio versus color transition were drawn and compared with the experimental data. It was found that 10-2 M-10-4 M sample solution could be determined in non-aqueous solvents.
