This technology report alerts upper-division undergraduate chemistry faculty and lecturers to the use of Texas Instruments emulators as virtual graphing calculators. These may be used in multimedia lectures to instruct students on the use of their graphing calculators to obtain solutions to complex chemical problems. (Contains 1 figure.)

In this extension to a classic physical chemistry experiment, students record the proton nuclear magnetic resonance spectra of the [beta]-diketones 2,4-pentanedione, 3-methyl-2,4-pentanedione, and 3-chloro-2,4-pentanedione to investigate the effect of substituents on keto-enol tautomerization equilibria. From the integrated intensities of keto and…

In 2005, the ACS Examinations Institute released an exam for first-term general chemistry in which items are intentionally paired with one conceptual and one traditional item. A second-term, paired-questions exam was released in 2007. This paper presents an empirical study of student performances on these two exams based on national samples of…

The percentage of students choosing the correct answer (PSCA) on 17 multiple-choice algorithmic questions taken from general chemistry exams is analyzed. PSCAs for these questions varied from 47 to 93%, and a decrease of 4.5% in PSCA was observed with each additional step in the algorithm required for solving the problem (R[superscript 2] = 0.80).…

It is a common complaint among teachers that students forget what they have learned soon after taking a test. The phenomenon is seen in both secondary and undergraduate chemistry courses. This study examines the length of time after a test that students in three different chemistry courses (undergraduate nursing, nonscience majors, and high school…

Successful completion of organic chemistry is a prerequisite for many graduate and professional programs in science, technology, engineering, and mathematics, yet the failure rate for this sequence of courses is notoriously high. To date, few studies have examined why some students succeed while others have difficulty in organic chemistry. This…

Educators are increasingly being called upon to provide evidence of student learning. Traditional assessments are not always the best venue for demonstrating conceptual understanding, particularly in science. This paper presents details on the design, use, and scoring of a performance-based assessment for measuring student understanding of…

The words used in the chemistry classroom often add to problems that students have in understanding complex concepts. This is particularly true when terms with specific scientific meanings are also used in colloquial speech with different meanings. This report discusses the results of student interviews that examine student comprehension of the…

This paper discusses a chemistry lesson plan based on the use of ethanol as an alternative and renewable energy source. The lessons were developed by participatory action research and follow a socio-critical and problem-oriented approach to chemistry teaching. This approach specifically focuses on the handling of scientific and technological…

A three-course sequence for first-year students that integrates beginning concepts in biology and chemistry has been designed. The first two courses that emphasize chemistry and its capacity to inform biological applications are described here. The content of the first course moves from small to large particles with an emphasis on membrane…

The double-helical structure of DNA is a pop cultural icon. Images of the DNA molecule appear in newspapers, popular journals, and advertisements. In addition to scientific instrument sales, the aura surrounding the central molecule of life has been used to sell everything from perfume to beverages and is the inspiration of items ranging from…

A simple algorithm was implemented in a spreadsheet program to simulate the circular dichroism spectra of proteins from their secondary structure content and to fit [alpha]-helix, [beta]-sheet, and random coil contents from experimental far-UV circular dichroism spectra. The physical basis of the method is briefly reviewed within the context of…

The effects of self-assembly on the hydrolysis kinetics of surfactants that contain ester bonds are discussed. A number of examples on how reaction rates and apparent reaction orders can be modulated by changes in the conditions, including an instance of apparent zero-order kinetics, are presented. Furthermore, it is shown that the examples on…

In this guided-inquiry activity, students investigate the ionization of strong and weak acids. Bead models are used to study acid ionization on a particulate level. Students analyze seven strong and weak acid models and make generalizations about the relationship between acid strength and dissociation. (Contains 1 table and 2 figures.)

Finding and describing the location of symmetry elements in complex objects is often a difficult skill to learn. Introducing the concepts of symmetry using high-symmetry game dice is one way of helping students overcome this difficulty in introductory physical chemistry classes. The dice are inexpensive, reusable, and come in a variety of shapes…