Gravimetric Complexometric Titration Method to Determine Mass Fraction of Ethylenediaminetetraacetic Acid Disodium Salt Dihydrate in Candidate-Certified Reference Materials

Abstract Titrations are a group of techniques that have contributed considerably to developing the chemical industry and chemistry itself. Currently, Consultative Committee for Amount Substance has recognized titration as one primary methods determining amount substance. In this context, an accurate gravimetric complexometric method was implemented determine purity ethylenediaminetetraacetic acid (EDTA) disodium salt dihydrate using lead nitrate-certified reference material (CRM). The reaction followed potentiometrically ion-selective electrode. equivalence point found by inflection non-parametric regression line fits experimental data. titrations were made in diluted ammonium hydroxide media sodium tartrate added avoid precipitation occurs at high pH. effect both concentrations, tartrate, evaluated Box-Behnken design. A complete uncertainty statement measurement is presented terms International System Units (SI). combined relative standard results 0.034 % EDTA salt. atomic weight applies nitrate CRM determined with mass spectrometry decrease budget contribution parameter which, otherwise, would been most important. main sources solution blanks, CRM, precision determination. no significant bias found. Finally, indicated developed could be used value assignment fraction produce CRMs.