Presenters' pedagogical choices are strongly affected by whether they view knowledge as coherent or fragmented. This mixed-methods survey study seeks to contribute to epistemological discussions and associated pedagogical suggestions in the context of mole ratio related mistakes evident in stoichiometry calculations performed by in-service…

Systematic errors are unfortunately common in analyses performed by students in teaching laboratories. Quality control (QC) tools are required to detect and solve bias in laboratory analyses. However, although QC has become routine in real-world laboratories, it is still rarely applied in teaching laboratories. For this reason, systematic errors…

Assessments can provide instructors and students with valuable information regarding student's level of knowledge and understanding, in order to improve both teaching and learning. In this study, we analyzed departmental assessment quizzes given to students at the start of Organic Chemistry 2, over an eight year period. This assessment quiz was…

This article reports the results of a curriculum survey of 322 analytical chemistry instructors (92% U.S.-based) conducted during Spring 2021. This snapshot of current course formats, topics, and pedagogical methods will be useful to both seasoned and novice teachers of analytical chemistry. The majority of respondents reported that their major…

In a university third-year instrumental chemistry laboratory students build a laser based polarimeter for determining light scattering with commercially available optical components used in modern optics research laboratories. During this laboratory experiment, students learn that solutions containing molecules which scatter light also influence…

The method of least-squares (LS) has a built-in procedure for estimating the standard errors (SEs) of the adjustable parameters in the fit model: They are the square roots of the diagonal elements of the covariance matrix. This means that one can use least-squares to obtain numerical values of propagated errors by defining the target quantities as…

Necessary and sufficient criteria for reaction spontaneity in a given direction and for spontaneity of finite transformations in single-reaction, closed systems are developed. The criteria are general in that they hold for reactions conducted under either conditions of constant T and p or constant T and V. These results are illustrated using a…

An inquiry-based laboratory exercise is described in which introductory chemistry students measure the density of water five times using either a beaker, a graduated cylinder, or a volumetric pipet. Students are also assigned to use one of two analytical balances, one of which is purposefully miscalibrated by 5%. Each group collects data using…

The mental models of both novice and advanced chemistry students were observed while the students performed a periodic table activity. The mental model framework seems to be an effective way of analyzing student behavior during learning activities. The analysis suggests that students do not recognize periodic trends through the examination of…

Complex error propagation is reduced to formula and data entry into a Mathcad worksheet or an Excel spreadsheet. The Mathcad routine uses both symbolic calculus analysis and Monte Carlo methods to propagate errors in a formula of up to four variables. Graphical output is used to clarify the contributions to the final error of each of the…

This study examines how well second-year nonmajor organic chemistry students are learning to draw, interpret, and understand resonance-related structures. Students were tested seven times throughout an academic year using a set of four tasks that reflected their understanding of what these structures represent and how they relate to each other.…

A statistical analysis of multiple-choice answers is performed to identify anomalies that can be used as evidence of student cheating. The ratio of exact errors in common (EEIC: two students put the same wrong answer for a question) to differences (D: two students get different answers) was found to be a good indicator of cheating under a wide…

A new Microsoft Excel spreadsheet design that enables a prompt calculation of rate constant, k values and associated errors and also addresses less common features such as the choice of an experimental curve's extent is presented. To complete the spreadsheet design, several highlights and squared colored boxes were included to assist the user and…

The cross-proportion method allows both the instructor and the student to easily determine where an error is made during problem solving. The C-P method supports a strong cognitive foundation upon which students can develop other diagnostic methods as they advance in chemistry and scientific careers.

Although Fischer's convention for stereoisomers is useful for simple molecules, the stereochemistry of complex biochemical molecules is often poorly indicated in textbooks. This article reports on errors in stereochemistry of complex hydrosoluble vitamin B12 molecule. Twenty-five popular biochemistry textbooks were examined for their treatment of…