Using data-driven activities with ChemEd X Data to practice structure-property relationships in General Chemistry

General Chemistry covers a wide variety of structure-property relationships that rely upon electronic, atomic, crystal or molecular factors. Giving students experimental data will allow them to identify the structure-property patterns as well as identify the limit of predictability of such patterns. “ChemEd X Data” is a web interface designed by the author that facilitates the navigation, filtering and graphical representation of chemical and physical data. It can assist students at identifying trends in structure-property relationships, they can create controlled experiments to test a relationship as well as investigating how different molecular factors may affect a single macroscopic property. In particular, since the site offers unstructured but dynamically searchable data, it is designed to have students learn control of variable strategies (CVS). This paper describes the implementation of a five-step sequence of activities related to structure-property relationships in a General Chemistry semester. ChemEd X Data is used for the open-ended or data-driven steps of this sequence. Student performance is analyzed with the objective of understanding which activities require a higher cognitive skill, as well as identify student previous performances that correlate with success in the activities and in the course in general.

IN QUEST OF A SYSTEMATIC FRAMEWORK FOR UNIFYING AND DEFINING NANOSCIENCE

This is an invited overview of a lecture presented at the American Physical Society (APS) Meeting, Boston, USA (March 1, 2012). The primary focus of this APS lecture was to trace the historical emergence of Hard and Soft nanoscale superatoms (i.e. nano-element categories) as well as a recent merging of these concepts/entities by chemists/physicists into a unified system and framework for defining nanoscience. The convergence of these quantized, organic/inorganic superatom entities involved the application of traditional "first principles" and their nanoscale "atom mimicry" features as a criteria for evolving a roadmap of quantized nano-elemental categories, nano-compound/assemblies and nano-periodic patterns, etc., much as was observed in traditional chemistry. This simple perspective was used to define a nanoscale taxonomy of hard/soft superatom/nano-element categories, as well as to explain the dependency of a broad range of nano-periodic properties/features on one or more of six Critical Nanoscale Design Parameters (CNDPs) associated with these nano-building blocks, namely: (1) size, (2) shape, (3) surface chemistry, (4) rigidity/flexibility, (5) architecture and (6) elemental composition. Validation and support of this systematic nano-periodic perspective has appeared in many recent publications describing CNDP dependent nano-periodic property patterns/trends, rules and Mendeleev-like nano-periodic tables which may unify and provide first steps toward a "central paradigm" for nanoscience.