Beer's law is an ideal technique that works only in certain situations. A method for dealing with more complex conditions needs to be integrated into the analytical chemistry curriculum. For that reason, the capabilities and limitations of two common chemometric algorithms, classical least squares (CLS) and principal component regression (PCR),…

Seven p-nitrophenyl benzoate esters (p-nitrophenyl benzoate, p-nitrophenyl m-anisate, p-nitrophenyl p-anisate, p-nitrophenyl m-chlorobenzoate, p-nitrophenyl p-chlorobenzoate, p-nitrophenyl m-toluate, p-nitrophenyl p-toluate) were synthesized and characterized by students in a second-semester organic laboratory course. In a subsequent laboratory…

This study aimed to investigate the comparative value of experimenting with physical manipulatives (PM) in a sequential combination with virtual manipulatives (VM), with the use of PM preceding the use of VM, and of experimenting with PM alone, with respect to changes in students' conceptual understanding in the domain of heat and temperature. A…

This study examines cognitive and social processes in group interactions that shape collaborative learning in science classrooms. Three small groups of students were observed while working collaboratively on explaining the burning of a candle under a jar. The learning environment served as a context for examination of conceptual convergence, a…

This paper describes a multifaceted agitation and mixing experiment. The relatively inexpensive apparatus includes a variable-speed stirrer motor, two polycarbonate tanks, and an instrumented torque table. Students measure torque as a function of stirrer speed, and use conductive tracer data to estimate two parameters of a flow model. The effect…

Interesting experiments on pressure and force can be performed by using dataloggers to measure exploding plastic film tubs.

A model lift containing a figure of Albert Einstein is released from the side of a tall building and its free fall is arrested by elastic ropes. This arrangement allows four simple experiments to be conducted in the lift to demonstrate the effects of free fall and show how they can lead to the concept of the equivalence of inertial and…

The analytical system to teach the subtleties of assaying alpha-dicarbonyl compounds in wine is described. Spectrophotometry is determined to be minimally useful in the experiment where the GC-MS (methyglyoxal) method proved to be ideal to confirm that the compounds analyzed in the wine samples were indeed the glyoxals based on the formation of…

A set of general principles underlying theory formation, theory revision, and experimentation are described. The manner in which these techniques may be integrated to provide a unified and comprehensive treatment of scientific theory development is demonstrated. In particular, the means by which experimentation is used to empirically guide and…

Describes the procedure to test the hypothesis that subjects' brain waves in response to a television flicker (distraction) would be smaller in amplitude during television programs of high, in contrast to low, interest. Results from 12 viewers support the hypothesis. (CP)

Summarizes findings of the deep sea drilling project at Scripps Institute of Oceanology. Results of Atlantic and Pacific Ocean drillings in terms of the composition and properties of the sea floor are discussed. (CP)

An article about musk oxen is used to introduce the role of clothing in keeping warm. Experiments for primary and advanced classes are included. (MT)

Presented is a annotated bibliography of science projects from the elementary through the professional level. (SJ)