The Analysis of Seawater: A Laboratory-Centered Learning Project in General Chemistry

Abstract

A laboratory-centered learning project for general chemistry on the analysis of seawater is described. Each laboratory section of 16–20 students is divided into teams of four students; each student works for three weeks on the project. Aggregation of all the class data gives the proximate total analysis (>99%) of the major ionic constituents of seawater. The experimental design includes both qualitative analysis for cations and anions and the quantitative analysis of four cations (Na+, K+, Mg2+, Ca2+) and three anions (Cl-, SO42-, Br-) by a variety of gravimetric, volumetric, and instrumental methods. During the three-week project each group writes two draft reports and a final report that summarizes the group's and class's experimental work. Each group member receives a grade based on the overall quality of the report as well as their contributions to the project.