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A Study Of Some Complexometric Titrations In Nonaqueous Solvents, Ngo The Hung

Masters Theses

"Complexometric titrations of calcium, zinc and lead with polyaminocarboxylic acids: ethylenediaminetetraacetic acid (EDTA), 1,2-diaminocyclohexanetetraacetic acid (DCTA), ethyleneglycol-bis(2-aminoethylether)tetraacetic acid (EGTA) and tetraethylenepentamine (tetren) have been investigated and compared in the following organic solvents: methanol, dimethyl formamide, dimethyl sulfoxide and methyl ethyl ketone. Various end point detection methods have been used: direct visual titration with metallochromic indicators and instrumental detection by photometry, potentiometry (mercury electrode and lead ion selective electrode) and amperometry. Calcium, zinc and lead can be determined up to trace levels (ppm) under specific conditions. A concrete application of this thesis is the determination of zinc or calcium in a …