Potentiometric determination of calcium and magnesium in seawater |
| |
Authors: | Jean Lebel Alain Poisson |
| |
Institution: | 1. Section d''Océanographie, Université du Québec à Rimouski, Rimouski, Qué. Canada;2. Laboratoire d''Océanographie Physique, Université Pierre et Marie Curie, Paris France |
| |
Abstract: | Methods are described for the complexometric determination of calcium and magnesium in seawater, using an amalgamated silver electrode for end-point detection. In the presence of a small amount of mercury(II)-chelonate, the amalgamated silver electrode serves as a pM indicator during the complexometric titration, the Hg complex being stronger than Ca, Mg and Sr complexes. Calcium is determined by titration with EGTA, calcium+magnesium+strontium by titration with EDTA and magnesium is obtained by difference. Average values of 0.02120 (standard deviation 0.00004) for Ca:Cl‰ and 0.06671 (standard deviation 0.00014) for Mg:Cl‰ were obtained for samples from tropical North Atlantic Ocean. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|