Date of Degree
Other Chemistry | Science and Mathematics Education
Gas Stoichiometry, Chemical Equilibrium, Hess' Cognitive Rigor Matrix, Bloom's Taxonomy, Depth of Knowledge, Misconceptions
The research presented as part of this dissertation is a combination of two separate studies conducted to assess and evaluate undergraduate general chemistry students’ understanding and depth of knowledge (DOK) of concepts in gas stoichiometry and chemical equilibrium. The two separate studies were conducted using a modified Hess Cognitive Rigor Matrix (CRM) to analyze students’ responses to multiple-choice questions (MCQ) and their written rationales to their answer choices. The Hess Cognitive Rigor Matrix, which is an incorporation and coordination of both Bloom’s and Webb’s DOK taxonomies, allowed the facilitation of the opportunity to code students’ written responses across the four levels of Webb’s DOK taxonomy. The major focal point of these studies was the assessment and evaluation of students’ written responses to their MCQ answer choices in order to better provide an insight into the level of each student’s understanding of the gas stoichiometry and chemical equilibrium concepts and any misconceptions they might hold.
The first study employed the use of the Hess’ CRM to determine undergraduate chemistry students’ (N = 38) DOK and any misconceptions they might have held about gas stoichiometry concepts. Informed by the first study, the second study employed the same method to determine undergraduate chemistry students’ (N = 261) DOK and misconceptions about concepts of chemical equilibrium. For the second study, unstructured interviews were also conducted (after students completed the pre and post questionnaires) with one focus group, to further investigate students’ written explanations to their MCQ answer choices. Participants in these two separate studies were students enrolled in a one-semester undergraduate level general chemistry course at one community urban college for the first study, and four community and three senior urban colleges for the second study. Greater than 95% of participants in each study were either science or engineering majors.
The findings from these two separate studies show independently that what students know, how much they know and misconceptions they might have held were not readily detected by their responses to the multiple-choice questions. Data analysis from both studies show that some students’ correct MCQ answer choices were supported by their incorrect explanations of gas stoichiometry and chemical equilibrium. Additionally, different degrees of misconceptions were detected within their written rationales for many of their correct answer choices.
The findings from these two separate studies suggest that assessment methods that are solely comprised of MCQ do not give instructors insight into students’ DOK or uncover any misconceptions they might hold of the concept(s) being assessed for. Additionally, the results of these two studies highlight the need for an assessment and evaluation method such as the one used in this research to better determine students’ DOK of chemical or other science concepts and detect any misconceptions they might hold of the concept(s) being assessed for.
Greene, Maria, "The Use of a Modified Hess’ Cognitive Rigor Matrix to Assess Students’ Depth of Knowledge in Key Concepts of Gas Stoichiometry and Chemical Equilibrium" (2020). CUNY Academic Works.