Study of the possibilities of determining mobile sulfur by physical-chemical and chemical methods in various substrates in the presence of orthanilic K

The article presents the results of testing the developed method for determining mobile sulfur in wood ash and various soil substrates. Determination of sulfur in sulfate form in presence of orthanilic K is possible due to the indicator’s ability to form coloured complexes with Ba²⁺ ion. We examined the ranges of volumetric and photometric determination. The accuracy of the analysis was determined by comparison with a certified method. We present optimal conditions for the successful determination of the mobile sulfur with the titration and with spectrophotometric method. The results of experiments confirming the capabilities of the method under study are presented.