Selective complexometric determination of mercury with sulphite as indirect masking reagent |
| |
Authors: | B Muralidhara Rao B Narayana |
| |
Institution: | (1) Department of Post-Graduate Studies and Research in Chemistry, Mangalore University, 574 199 Mangalagangothri, India;(2) Present address: Department of Chemistry, Govinda Dasa College, 574 158 Suratkal, India |
| |
Abstract: | A complexo-titrimetric method for the determination of mercury(II) in the presence of other metal ions is described, based on the selective masking ability of sulphite ion towards Hg(II). Mercury in a given sample solution is initially complexed with a known excess of EDTA and the surplus EDTA titrated with zinc sulphate solution at pH 5.0–6.0 (hexamine), using xylenol orange (or methylthymol blue) as indicator. An excess of solid sodium sulphite is then added to decompose the Hg(II)-EDTA complex and the released EDTA is titrated with standard zinc sulphate solution. Reproducible and accurate results are obtained for 9.9–99 mg Hg with relative errors < 0.35% and standard deviations < 0.05 mg. The effects of various cations and anions are studied. |
| |
Keywords: | mercury determination EDTA titration complexometry masking sodium sulphite |
本文献已被 SpringerLink 等数据库收录! |