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This paper reports a laboratory experiment that determines the kinetics of the reaction of coumarin-102, a fluorescent dye, with sodium hydroxide. The reaction is studied by monitoring the loss of coumarin-102 fluorescence during ring-opening saponification by hydroxide using smartphone cameras and near-UV (“blacklight”) illumination. The order of the reaction in coumarin-102 is determined by examining the time course of fluorescence decay over time and fitting the data to integrated rate law models. The order of the reaction in sodium hydroxide is determined by varying the concentration of NaOH and comparing the impact on the rate of the reaction. This represents an easy-to-implement kinetics experiment that uses an engaging phenomenon (fluorescence), a convenient data-acquisition technology (smartphone cameras) and an important image-processing software program (ImageJ). This gives students the ability to work with the determination of the rate law for both coumarin-102 and for sodium hydroxide, using complementary methods. This experiment is both informative and enjoyable for students, enabling them to directly observe kinetics—quite literally with open eyes—making scientific concepts more tangible and engaging. The experiment has also been adapted in a manner consistent with the principles of evidence-centered design using content of kinetics and the scientific practice of mathematical reasoning. 

The phenomenon of fluorescence is very important from multiple standpoints in the chemical and biological sciences. This paper introduces an experiment in a first-semester chemistry laboratory course that uses a current biomedical research method, the detection of double-stranded DNA using the intercalator propidium iodide. Fluorescence is detected both using blacklight illumination and also with white light and a spectrometer, using the two excitation bands for propidium. This experiment also involves students obtaining DNA from strawberries and then determining the amount of DNA they have isolated using fluorescence methods. The experiment provides students with an initial experience in fluorescence-based analytical chemistry and the concepts of fluorescence as a quantum phenomenon. 

This paper presents a phenomenographic investigation on students’ experiences about research and poster presentations in a workshop-based undergraduate research experience with a focus on how the experience connects to the Science and Engineering Practices (SEPs) of the NRC A Framework for K-12 Science Education and the principles of CUREs. This provides insight into how these structured research experiences reflect particular SEPs and also elements of scientific practice that are not captured in the SEPs as they have been formulated previously. This work showcases the importance of future applications, failure, and creativity as additional science practices necessary for students to engage in authentic science. The SEPs and the additional elements of scientific practice are related to how students experience meaningful learning in the cognitive, psychomotor, and affective domains. Students highlighted the components of CUREs: importance of contributing relevant discoveries as a motivation for their research, the value of repetition and iteration in ensuring reliable and valid results, and the role of collaboration in seeing new perspectives and solving problems. As a result of presenting their results through a poster, students reported deeper understanding of their research topic, increased ability to articulate scientific concepts, and a better understanding of how to create a visually appealing poster. Students changed the vocabulary they used in their presentations to fit the knowledge level of their audience and highlighted their data in figures and explained other parts of their work in text. Moreover, they saw the poster as an outlet for their creativity. 

A key part of the practice of chemistry is the analysis of chemical composition, including through gravimetric analysis and spectrophotometry. However, the complexity of doing multiple calculations to obtain analytical evidence, such as that required to determine an empirical formula, presents a challenge if such analytical methods are to be understood by students and if they are to support meaningful learning about other chemical concepts and methods. In this study we investigate student use of spectrophotometry and gravimetric analysis to determine the number of water molecules in hydrates of copper (II) salts, a method previously described by Barlag and Nyasulu. Using phenomenography to analyze students reports through the lens of meaningful learning we identified four distinct perceptions and, within them, information of how students make sense of the complex analytical steps involved in the experiment. We identify how meaningful learning is present where students recognized that spectrophotometry was based on light-matter interactions (cognitive,) was faster and more accurate (psychomotor), and allowed students to express confidence in the process and their results (affective). However, it is also the case that meaningful learning was compromised where students had trouble conceptualizing spectrophotometry, saw it as a set of disconnected steps, and where they saw absorbance as a computer-generated value and not a property of the solution. This led to the perception that gravimetric analysis provided a more direct and understandable technique. We discuss the implications of these findings for chemistry education research (CER) and for curriculum development in the undergraduate teaching lab. 

We previously observed students gesturing during a symmetry and group theory activity. This prompted additional interviews wherein we attempted to understand the semiotic function of these gestures. We report here on the gestures which students have used in this context to represent symmetry elements, symmetry operations, and other related ideas. In the process, we have developed a scheme to code gestures in a systematic way that enables qualitative analysis and may lend itself to quantitative methods. This analysis leads to two observables: physical forms and motions enacted while representing or thinking about symmetry. These gestures are metaphorical and allow us to infer cognitive notions underlying the gesture as part of the student’s reasoning, their communication, or both. Characterizing these gestures and associated notions offers the opportunity to add to our understanding of how gesture and other embodied representations can systematically support student learning in relation to spatial concepts and descriptions in chemistry. This characterization also has implications for instruction to support student learning about symmetry in inorganic chemistry. 

Reading and understanding scientific literature is an essential skill for any scientist to learn. While students’ scientific literacy can be improved by reading research articles, an article’s technical language and structure can hinder students’ understanding of the scientific material. Furthermore, many students struggle with interpreting graphs and other models of data commonly found in scientific literature. To introduce students to scientific literature and promote improved understanding of data and graphs, we developed a guided-inquiry activity adapted from a research article on snow chemistry and implemented it in a general chemistry laboratory course. Here, we describe how we adapted figures from the primary literature source and developed questions to scaffold the guided-inquiry activity. Results from semi-structured qualitative interviews suggest that students learn about snow chemistry processes and engage in scientific practices, including data analysis and interpretation, through this activity. This activity is applicable in other introductory science courses as educators can adapt most scientific articles into a guided-inquiry activity. 

A significant challenge to the community of chemistry education is the creation of materials that can be used in nonscience settings, including those of social science and humanities classrooms. As part of a larger effort to engage new communities in understanding how science data can impact such settings, including in the community, an experiment to detect the level of nitrogen oxides (NOx) in the air was implemented in university sociology and history classrooms. The use of an authentic scientific method within these settings generated important data for classroom use in classroom sociological and historical discussions. The impact on student attitudes and learning was also determined.