Complexo-titrimetric determination of mercury using hexahydropyrimidine-2-thione as a selective masking agent  

作　　者：NARAYANA  B. KUCHINAD  T. Girish GAJENDRAGAD  M. R. 

机构地区：[1]Department of Studies in Chemistry, Mangalore University Mangalagangothri 574 199, Karnataka State, India [2]Kuvempu University, B.R. Project, Shlmoga 577115, India

出　　处：《Chinese Journal of Chemistry》1992年第5期412-416,共0页中国化学（英文版）

摘　　要：A simple, rapid, accurate and selective complexometric method is proposed for the determina- tion of mercury(Ⅱ). Mercury(Ⅱ) is first complexed with a known excess of EDTA and the surplus EDTA is back-titrated at pH 5. 0--6. 0 with lead nitrate, xylenol orange being used as indicator. Hexa- hydropyrimidine-2-thione (HPT) is then added to displace EDTA from the Hg-EDTA complex quan- titatively and the EDTA released is titrated with lead nitrate. Reproducible and accurate results are obtained for 2--55 mg of mercury, with a relative error of less than 0. 5% and standard deviation of less than 0.04.A simple, rapid, accurate and selective complexometric method is proposed for the determina- tion of mercury(Ⅱ). Mercury(Ⅱ) is first complexed with a known excess of EDTA and the surplus EDTA is back-titrated at pH 5. 0--6. 0 with lead nitrate, xylenol orange being used as indicator. Hexa- hydropyrimidine-2-thione (HPT) is then added to displace EDTA from the Hg-EDTA complex quan- titatively and the EDTA released is titrated with lead nitrate. Reproducible and accurate results are obtained for 2--55 mg of mercury, with a relative error of less than 0. 5% and standard deviation of less than 0.04.

分 类 号：O6[理学—化学]