The Chemical EducatorISSN: 1430-4171 (electronic version) Abstract Volume 23
(2018) pp 93-95 Simply Modified Optical Cuvettes for Microscale Process
Monitoring: A Solid-Phase Extraction Experiment Illustrating their Fabrication
and Use
Paul A. Flowers Chemistry & Physics Department, University of North Carolina at Pembroke, Pembroke NC 28372, paul.flowers@uncp.edu Published: 12 May 2018 Abstract. A versatile approach for modifying standard optical cuvettes to permit their use as microscale reaction vessels in undergraduate chemistry labs is described. This approach is illustrated by a student experiment involving the solid-phase extraction of aqueous dye mixtures using a solution-deposited ion-exchange polymer (Nafion). Visual observations and photometric measurements are used to determine the film’s equilibration time, charge selectivity, and extraction efficiency for a cationic dye, methylene blue, both alone in solution and in the presence of an anionic dye, tartrazine. This experiment has been implemented in several different laboratory sections of a sophomore analytical chemistry course, yielding consistently good results and generating considerable student interest. Suggestions are provided for several variations and extensions of this general experimental scheme.
Key Words: Laboratories and Demonstrations; analytical chemistry; microscale; solid-phase extraction (*) Corresponding author. (E-mail: paul.flowers@uncp.edu) Article in PDF format (231 KB) HTML format Supporting Materials: Two PDF files are available as supporting material; a student handout and instructor notes. (786 KB)
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