Trisethylenediaminecobalt(III) Chloride Sulfate as a Subject Material for Widely Different Chemistry Lab Courses

Abstract

To make the chemistry lab class more effective within the limits of class hours and equipment available at a small college, I previously reported the integrated and unified lab curricula in inorganic, analytical, and physical chemistry, using Mohr's salt (Fe(NH4)2(SO4)2.6H2O) or a cobalt complex such as [CoCl2(en)2]Cl. In this report, I describe a new unified lab curriculum, expanded to include an organic chemistry or stereochemistry lab course using rac-tris(ethylenediamine)cobalt(III)chloridesulfate (rac-[Co(en)3]ClSO4). The teaching material has been used to unify several lab courses as follows: preparation of testing material and identification by electronic spectrum (inorganic lab), elemental analyses of cobalt, chloride, and sulfate (analytical lab), optical resolution of diastereoisomers (organic or stereochemistry lab), kinetics of racemization (physical chemistry lab).