Indirect Complexometric Determination of Mercury Using Potassium Iodide as Selective Masking Agent

Authors : B Muralidhara RAO

Pages : 215-220

View : 14 | Download : 10

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :This paper describes a indirect complexometric method for the determination of mercury in the presence of co-ions, based on the selective masking ability of potassium iodide. To the mixture of mercury insert ignore into journalissuearticles values(II); and other metal ion solution, EDTA solution was added in excess of the metal ions present. The pH of the solution was adjusted to 5.0-6.0 using solid hexamine insert ignore into journalissuearticles values(10 \pm 2 g); and surplus EDTA was titrated with zinc sulfate solution using xylenol orange indicator. An excess of solid potassium iodide was then added to decompose the Hg-EDTA complex and the released EDTA was titrated with standard zinc sulfate solution. Accurate results were obtained for 4.5-80 mg insert ignore into journalissuearticles values(2.24 \times 10-5 M - 3.99 \times 10-4 M); of mercury with relative errors \leq 0.4 %, standard deviations \leq 0.07 mg. Sninsert ignore into journalissuearticles values(IV); and Auinsert ignore into journalissuearticles values(III); interferes but can be masked using sodium fluoride. The method can be applied in the analysis of mercury in its alloys and complexes.
Keywords : complexometry, EDTA, mercury determination, potassium iodide, masking agent