Impact of Assessment Emphasis on Organic Chemistry Students' Explanations for an Alkene Addition Reaction

Autor/inn/en	DeGlopper, Kimberly S.; Schwarz, Cara E.; Ellias, Niall J.; Stowe, Ryan L.
Titel	Impact of Assessment Emphasis on Organic Chemistry Students' Explanations for an Alkene Addition Reaction
Quelle	In: Journal of Chemical Education, 99 (2022) 3, S.1368-1382 (15 Seiten)Infoseite zur Zeitschrift PDF als Volltext Verfügbarkeit
Zusatzinformation	ORCID (Schwarz, Cara E.) ORCID (Stowe, Ryan L.)
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0021-9584
DOI	10.1021/acs.jchemed.1c01080
Schlagwörter	Science Instruction; Organic Chemistry; Scientific Concepts; Concept Formation; Science Tests; Student Evaluation; Evaluation Methods; Energy; Correlation; Teaching Methods + Suchen Sie Ihr Suchwort? Teaching of science; Science education; Natural sciences Lessons; Naturwissenschaftlicher Unterricht; Organische Chemie; Concept learning; Begriffsbildung; Schulnote; Studentische Bewertung; Energie; Korrelation; Teaching method; Lehrmethode; Unterrichtsmethode
Abstract	To potentially engage students in "doing organic chemistry", organic chemistry courses should foreground weaving together structure- and energy-related ideas to construct causal accounts for phenomena. Here, we investigate whether enrolling in an organic chemistry course that places substantial emphasis ([approximately]50% of total points) on explaining phenomena on exams is associated with more productively justifying the outcome of a chemical process. This work occurred in the context of three learning environments that differed principally by assessment emphasis. The "explanation focused" course allotted 40-66% of points on exams to explaining phenomena while the other two enactments placed much less emphasis on connecting big ideas to how and why chemical processes occur ([approximately]0-25% of total points). Students enrolled in each course were given a prompt which asked them to draw mechanisms for a hydrobromination reaction and subsequently justify the regiochemical outcome of that reaction. We described student responses by noting the connections made between structure (of reactants, intermediates, transition states, or products) and energy. Most students described how charge or electron delocalization impacted the relative energies of the two possible intermediates or transition states. Other explanations invoked steric repulsion or differences in relative energy due to the degree of carbocation substitution. An examination of the association between learning environment enrollment and explanation code distribution revealed that students who enrolled in two semesters of an explanation-focused course were substantially "less" likely to leave out charge delocalization in their explanations while students who were never enrolled in the explanation-focused learning environment were substantially "more" likely to leave out charge delocalization. These findings suggest that changing what is assessed to better align with "doing organic chemistry" may be a promising avenue for reform. (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	2024/1/01