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Knowledge and Skills Statement

Science concepts. The student understands how matter is accounted for in chemical substance.

any material that has a definite chemical composition

a pure substance that is made up of one type of molecule

material substance that occupies space, has mass, and is composed predominantly of microscopic particles

Research

Hanson, Ruby. "Ghanaian Teacher Trainees’ Conceptual Understanding of Stoichiometry." Journal of Education and E-Learning Research 3, no. 1 (2016): 1–8. https://doi.org/10.20448/journal.509/2016.3.1/509.1.1.8

Summary An interpretive study on trainees’ conceptual understanding of chemical stoichiometry was carried out among 78 teacher trainees in their second year of study. The interpretation indicated that their learning of stoichiometry was basically through the use of picket fence (factor label), undefined strategies and algorithm. The trainees were found to have more persistent problems with conceptual interpretation as they were not able to fully translate word problems into mathematical equations regardless their algorithmic underpinnings. Neither did they understand fully, the law of conservation of matter.

Research

Wagner, Eugene P. "A Study Comparing the Efficacy of a Mole Ratio Flow Chart to Dimensional Analysis for Teaching Reaction Stoichiometry." School Science and Mathematics 101, no. 1 (2001): 10-22. doi:10.1111/j.1949-8594.2001.tb18185.x.

Summary Stoichiometry has long been a nemesis of students in general chemistry. Described here is a proportional reasoning methodology called the Mole Ratio Flow Chart (MRFC) that has been developed and used over the past 2 years in the investigator's general chemistry courses. A study was conducted in the spring 1999 and fall 1999 semesters in the Chemistry 1251 course to determine the relative efficacy of the MRFC compared to dimensional analysis for student performance and understanding of reaction stoichiometry.