Maximum acceptable deviations from additivity in the photometric analysis of two-component mixtures by Firordt’s method

• Published in: Journal of analytical chemistry (New York, N.Y.) Vol. 65; no. 5; pp. 466 - 472
• Main Authors: Vlasova, I. V., Isachenko, N. A., Shilova, A. V.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01-05-2010; Springer
• Subjects: Algorithms; Analysis; Analytical Chemistry; Chemistry; Chemistry and Materials Science; Methods; Theobromine; Acceptable Deviation; Determi Nation; Photometric Analysis; Analytical Wavelength
• ISSN: 1061-9348; 1608-3199
• DOI: 10.1134/S1061934810050060

Photometric analysis of mixtures by Firordt’s method yields relative errors that do not exceed the specified limits only if the deviations from additivity at the analytical wavelengths do not exceed (in their numerical value) their own critical values (δ
A
crit
). These deviations depend on the ratio of component concentrations. By virtue of the analytical geometry technique, we derived equations for the evaluation of δ
A
crit
. These equations allow one to predict the possibility of the precise determination of two components in a mixture under investigation at one and the same set of wavelengths. The developed algorithm was verified on 40 model mixtures of organic compounds.