A Study Comparing the Efficacy of a Mole Ratio Flow Chart to Dimensional Analysis for Teaching Reaction Stoichiometry

Abstract

Reaction stoichiometry calculations have always been difficult for students. This is due to the many different facets the student must master, such as the mole concept, balancing chemical equations, algebraic procedures, and interpretation of a word problem into mathematical equations. Dimensional analysis is one of the main ways students are taught to solve these problems. However, this methodology does not provide all students with a complete understanding of how to solve these problems. Introduction of alternative problem solving techniques, such as proportional reasoning, can help to improve student understanding. The mole ratio flow chart (MRFC) is a logistical sequence of steps that incorporates molar proportions. Students are able to begin analysis of a problem from many different starting points using this MRFC method. Analyses of data collected indicate that MRFC users performed as well on exam problems covering reaction stoichiometry calculations as students using dimensional analysis. Further, class sections exposed to both dimensional analysis and MRFC methods scored as well on exam problems as class sections exposed only to dimensional analysis. These results indicate that the MRFC is a viable alternative method for teaching reaction stoichiometry calculations and for helping to create a more complete understanding of the subject.

Development of procedure for the assessment of cognitive complexity of stoichiometric tasks

“…However, students consider this area difficult, abstract and unattractive [2], because solving stoichiometric problems and mastering stoichiometric concepts requires skills, such as writing and balancing chemical equations, and the quantitative chemical calculations of mass, volume, quantity, number of particles and others [3]. In addition, the complexity of calculations, requiring mathematical skills and the transformation of text into procedural steps, contributes to the unpopularity of stoichiometry as well [4].…”

The Efficacy of Concept Mapping Instructional Strategy in Remedying Students' Problem-Solving Difficulties in Stoichiometry

“…The difficulty in learning chemistry has been established by a number of research works (Gongden, 1998;Ezeudu, 2000;Jimoh, 2004& Njoku, 2007). Similarly, other research works have established students' poor performance in chemistry problem solving tasks (Crippen, Brooks, & Courtright, 2000;Wagner, 2001;Danjuma, 2005). These researches along with WAEC chief examiners' reports (1995,1999,2000,2003,2005,2007) revealed the chemistry concepts (mostly physical chemistry) with which students experience difficulty in solving chemical problems and which contribute to students' failures in examinations.…”

“…The poor performance of chemistry students in problem solving has been established by a number of researches amongst which are Cripen, Brooks & Courtright (2000); Wagner (2001) and Danjuma (2005). Some of the concepts that present such difficulty to students include electrochemistry, chemical equilibrium, redox reactions, mole concept and stoichiometry.…”

“…Reaction stoichiometric calculations have been difficult for students (Wagner, 2001). This is hinged on the mathematical and practical nature of the subject.…”

Student Understanding of Scale: From Additive to Multiplicative Reasoning in the Constriction of Scale Representation by Ordering Objects in a Number Line

“…(Booth & Siegler, 2006& 2008Dehaene, 2011;Kadosh, Tzelgov, & Henik, 2008;Lamon, 1993;Lesh, Post, & Behr, 1988;Piaget, 1987;Reys, Lindquist, Lambdin, & Smith, 2009;Siegler & Opfer, 2003;Smith & Confrey, 1994;Vergnaud, 1983 (An, 2008;Hart, 1981Hart, & 1988Kamii & Livingston, 1994;Lindquist, 1989;O'Brien & Casey, 1983;Siemon, Breed, & Virgona, 2006;Siemon & Virgona, 2001 (Ben-Chaim et al, 1998;Kim & Bang, 2013;Lesh, Post, & Behr, 1988;Tournaire & Pulos, 1985 (Akatugba & Wallace, 1999;Angell et al, 2008;Beland & Mislevy, 1996;De Lozano & Cardenas, 2002;Guckin & Morrison, 1991;Hines & McMahon, 2005;Lamon, 1993;Prain & Waldrip, 2006). (Bar, 1987;Dawkins et al, 2008;Evans et al, 2008;Kohn, 1993;Smith, 1997;Streefland, 1984;Wagner, 2001). "수학은 쉬운데 과학은 어렵다?"…”