Field and In-Lab Determination of Ca2+ in Seawater

Autor:	Jose R. Rodriguez Nuñez, Robin Stoodley, Tessa Bartz
Rok vydání:	2014
Předmět:	Field (physics) Chemistry Instrumentation Potentiometric titration Calcium concentration Analytical chemistry Titration Seawater General Chemistry Sample collection Quantitative analysis (chemistry) Education
Zdroj:	Journal of Chemical Education. 91:1954-1957
ISSN:	1938-1328 0021-9584
DOI:	10.1021/ed4005722
Popis:	Portions of classic undergraduate quantitative analysis experiments in complexiometric titration and potentiometry are combined with a field-sampling experience to create a two period (2 × 3 h) comparison-based experiment for second-year students. A multifunctional chemical analysis device is used with calcium ion-selective electrode for field measurement of calcium concentration in seawater. The results are compared with later simultaneous potentiometric and colorimetric titration with ethylenediaminetetraacetic acid (EDTA). Students compare precision, difficulty, and sources of error of the different methods and present a written argument supporting their choice of best method including advantages and limitations. The experiment provides an introduction to chemistry in-the-field, sample collection and handling, complex matrices, imperfect methods, fallibility of instrumentation, real-world performance, and decision-making.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::c8da48942e0c7402357f0be2f23ca58a https://doi.org/10.1021/ed4005722 Zobrazit plný text záznamu