Juicing the Juice: A Laboratory-Based Case Study for an Instrumental Analytical Chemistry Course

Abstract

A variety of nontraditional instructional approaches have been described in recent times. Peer-led instruction (1), problembased instruction (2), guided-inquiry learning (3), team learning (4), and case-study teaching (5) are examples of these innovative pedagogies. Case-study teaching has proved successful at this institution (6-8) and elsewhere (9)(10)(11)(12)(13)(14).Case-based laboratories are a variation on case-study teaching and offer students a better approximation of real science than conventional undergraduate laboratory experiments. The laboratories are based upon real-world stories that involve characters students can identify with and ask students to deal with problems that challenge their creativity in ways that conventional "cookbook" laboratory experiments do not. Case-based experiments should, to the extent possible, require students to develop their own plan for dealing with the problem(s) posed by the case and to critically assess and apply their experimental data. Case-based experiments should also require students to write a narrative report explaining how their data were obtained and applied, the significance of their results, and how their results answer or fail to answer the problem(s) associated with the case. A well-designed laboratory-based case study should tell a story that the student audience can identify with and that has an experimental solution. It should require student teamwork and involve minimal faculty guidance. Good cases should be brief and structured in a manner that allows student to develop a feeling of ownership for the experimental approach that they design. The instructor's role should, ideally, focus on answering student questions and assessing the safety and effectiveness of the experimental procedures that the student teams propose to deal with the case's problem(s). Safety is of primary importance and must be stressed when evaluating the experimental plan the students develop to attack the case.The "Juicing the Juice" case study requires small teams of students to conduct themselves as chemists would in the "real world". The laboratory instructor provides students with the case study 1 week prior to the laboratory. The student teams must develop their own experimental approach to the problem posed in the case. During a 1-h prelaboratory session, the instructor provides a general overview of the case, emphasizes safety issues, answers questions, and begins the process of reviewing team approach plans. The approach plan must meet with the approval of the instructor before a team is allowed to begin the experiment. Student teams then collect appropriate quantitative data and interpret and apply those data. In the process, students are exposed to the use of an inductively coupled plasma (ICP) spectrometer, application of least-squares analysis to the data collected, data interpretation, the application of statistical analysis to determine whether samples significantly differ, and the writing of a narrative report based on their analysis. The Case StudyThis laboratory...

Examining Some of the Challenges Students Face in Learning about Solubility and the Dissolution Process

“…There are a variety of approaches that instructors in order to help students in their better understanding the material of a particular course. Some of those approaches include, problem-based instruction, team learning, guided-inquiry learning, and case study (Schaber et al, 2010).…”

Desenvolvimento e avaliação de casos para o ensino de mecanismo de reação

“…Em especial, na educação em Química, considerando-se, também, as divulgações da área, a abordagem investigativa é vista como uma estratégia que gera reações muito positivas nos alunos, como o interesse e compreensão pelas aulas de Química. Tal benefício, além dos já destacados, como o protagonismo do aluno, contextualização, articulação dos conceitos científicos com o cotidiano, entre outros, permite aos alunos terem uma melhor percepção do mundo que os cerca e verem, nas situações da vida real, que a Química da sala de aula está em ação (SCHABER, 2011;CAMPBELL, POWERS, ZHENG, 2016;CHOWDHURY, 2013;DIESEL, BALDEZ, MARTINS, 2017).…”

Students as Investigators: Promoting Active Learning through a Case Study Assignment in a Lecture-Based Analytical Chemistry Course

“…Several case study assignments have been published previously including a murder mystery, 10 authentication of orange juice in the laboratory, 11 detection of contaminants 12−14 and poison, 15 among other publications. 16−19 To our knowledge, some of these case studies involve at least one laboratory component that requires hands-on sample analysis and, as such, cannot be used in a lecture-based course.…”

“…Several case study assignments have been published previously including a murder mystery, authentication of orange juice in the laboratory, detection of contaminants − and poison, among other publications. − To our knowledge, some of these case studies involve at least one laboratory component that requires hands-on sample analysis and, as such, cannot be used in a lecture-based course. Others provide students with data sets and require data analysis; however, they lack the critical thinking and interactive components offered by the requisition form, as well as the creative freedom given to students in the case study assignment described herein.…”