The addition of the Lewis acid, Sc(OTf)3, to 2,2′-azobis(2-methylpropionitrile) (AIBN)-initiated copolymerizations of both methyl acrylate (MA) and methyl methacrylate (MMA) with 1-alkenes results in increased reaction rate and increased incorporation of the latter monomer into the polymer backbone. As little as 4 mol % of the Lewis acid is effective in forming a nearly alternating copolymer of MA and ethene at 67% MA conversion. This procedure allows for the control of copolymer composition independent of the starting monomer feed ratio.

We have conducted an investigation into how well students in introductory science classes (both physics and chemistry) are able to predict which questions they will or will not be able to answer correctly on an upcoming assessment. An examination of the data at the level of students' overall scores reveals results consistent with the Dunning-Kruger effect, in which low-performing students tend to overestimate their abilities, while high-performing students estimate their abilities more accurately. Similar results have been widely reported in the science education literature. Breaking results out by students' responses to individual questions, however, reveals that students of all ability levels have difficulty distinguishing questions which they are able to answer correctly from those that they are not able to answer correctly. These results have implications for the future study and reporting of students' metacognitive abilities.

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This paper describes an interdisciplinary investigation of students' usage of ideas about energy from physics in the context of introductory chemistry. We focus on student understanding of the idea that potential energy is a function of distance between interacting objects, a concept relevant to understanding potential energy in both physical and chemical contexts. Data from student responses to written surveys and focus-group interviews reveal that students do not spontaneously make connections between ideas they have about energy from physics classes and the understanding of energy that they develop in chemistry. We describe the development of a sequence of questions that appears to aid students in drawing these connections appropriately. We also document students' as they are confronted with and struggle to resolve the mismatch between their energy ideas from physics and chemistry.