Improving Student Results in the Crystal Violet Chemical Kinetics Experiment

Autor/inn/en	Kazmierczak, Nathanael; Vander Griend, Douglas A.
Titel	Improving Student Results in the Crystal Violet Chemical Kinetics Experiment
Quelle	In: Journal of Chemical Education, 94 (2017) 1, S.61-66 (6 Seiten)Infoseite zur Zeitschrift PDF als Volltext Verfügbarkeit
Zusatzinformation	ORCID (Vander Griend, Douglas A.)
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0021-9584
DOI	10.1021/acs.jchemed.6b00408
Schlagwörter	Kinetics; Chemistry; Science Instruction; Science Experiments; Laboratory Experiments; Laboratory Procedures; Color; College Science; Secondary School Science; Regression (Statistics); High School Students; College Freshmen + Suchen Sie Ihr Suchwort? Kinetik; Chemie; Teaching of science; Science education; Natural sciences Lessons; Naturwissenschaftlicher Unterricht; Laboratory work; Laborarbeit; Laboruntersuchung; Colour; Farbbezeichnung; Farbe; Regression; Regressionsanalyse; High school; High schools; Student; Students; Oberschule; Schüler; Schülerin; Studentin; Studienanfänger
Abstract	Despite widespread use in general chemistry laboratories, the crystal violet chemical kinetics experiment frequently suffers from erroneous student results. Student calculations for the reaction order in hydroxide often contain large asymmetric errors, pointing to the presence of systematic error. Through a combination of "in silico" synthetic data simulations and laboratory experimentation, we report on five potential sources of error: (1) the kinetic flooding approximation, (2) solution concentration mistakes, (3) signal processing, (4) spectrometer limitations, and (5) particulates in the solution. The majority of this asymmetric error can be eliminated by constraining the data collection region within spectrometer limitations, specifically 0.7-0.1 Abs for a SpectroVis+ spectrophotometer. The consistent detection of particulate formation during the later course of the reaction is an aspect of the reaction not previously explored. Guidelines for optimizing laboratory procedure, instruments, and software are provided. (As Provided).
Anmerkungen	Division of Chemical Education, Inc and ACS Publications Division of the American Chemical Society. 1155 Sixteenth Street NW, Washington, DC 20036. Tel: 800-227-5558; Tel: 202-872-4600; e-mail: eic@jce.acs.org; Web site: http://pubs.acs.org/jchemeduc
Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2020/1/01