Methods and optics of perceiving color in a black-and-white grating are described. A sample grating which produces the effect is included. (JN)

Suggested in this article are experiments that can be used in the classroom, are inexpensive, need simple equipment, and are easy for the children to conduct. (RB)

Science experiments that can be done at home are described and illustrated. (DB)

An experiment is conducted to measure the enthalpy of vaporization of volatile compounds like methylene chloride, carbon tetrachloride, and others by using gas chromatography. This physical property was measured using a very tiny quantity of sample revealing that it is possible to measure the enthalpies of two or more compounds at the same time.

A simple conductivity instrument in nonaqueous solvents is employed to project several features of the SN2 mechanism, which involves the Finkelstein reaction. The effects of the different variables of the SN2 mechanism are described.

The preparation of 7-hydroxy-3-carboxycoumarin starting from 2,4-dihydroxybenzaldehyde, and malonitrile, by one-pot consecutive reactions, carried out in water under heterogenous conditions is presented. The experiment encourages students to think in terms of reaction mechanisms.

The purpose of this research was to determine how metal oxide used in a thermite reaction can impact the production of nanoparticles. The results showed the presence of nanoparticles (less than 1 micron in diameter) of at least one type produced by each metal oxide. The typical particles were metallic spheres, which ranged from 300 nanometers in…

The experiment to measure concentration of Photophysical Characterization(BHT) and determine percent recovery in chewing gum is described. The results demonstrated that over time, the concentration of BHT in the extract decreased owing to aerial oxidation.

We present an identification key to the common rodent prey found in owl pellets from the Northwestern (NW) and Southeastern (SE) United States that is based on differences in incisor size (arc diameter) among genera.

Gerald Rutherford (1964), one of the original authors of the Harvard Project Physics course which emphasized the history of science, expressed a view of inquiry which advocated the historical re-constructions of significant experiments. To implement this view we examine two modes of historical re-constructions; Heering's ("Paper…

We have recently developed and implemented two experiments in biomolecular NMR for an undergraduate-level biophysical chemistry laboratory with commercially available [subscript 15]N-enriched human ubiquitin. These experiments take advantage of [subscript 15]N direct detection of the NMR signal. The first experiment develops skills in acquiring…

Evolution is typically measured as a change in allele or genotype frequencies over one or more generations. Consequently, evolution is difficult to show experimentally in a semester-long lab course because most organisms have longer generation times than 15 weeks. In this article, the authors present an experiment to demonstrate and study…

This paper illustrates a new and practical experimental technique for studying the Doppler effect where the pitch variation of noise from a passing aircraft is used to calculate its speed.

Permanent magnets have long been used in both traditional laboratory exercises and in inquiry-based learning activities. These pedagogical applications are typically timed to correspond to the early coverage of magnetism in the second-semester sequence of introductory physics. At the initial level the concepts relate to the magnetic field of the…