In this paper, we show the potential of webcams as precision measuring instruments in a physics laboratory. Various sources of error appearing in 2D coordinate measurements using low-cost commercial webcams are discussed, quantifying their impact on accuracy and precision, and simple procedures to control these sources of error are presented.…

Since 1999, Slovenia has been in the process of introducing nine years of compulsory education to replace the previous eight-year system of compulsory education. Under the new system, the school entry age is six years rather than the former seven years. This reform of the system necessitated a number of other changes, such as those relating to the…

Biobottles are miniature ecosystems made from 2-liter plastic soda bottles. They allow students to explore how organisms in an ecosystem are connected to each other, examine how biotic and abiotic factors influence plant and animal growth and development, and discover how important biodiversity is to an ecosystem. This activity was inspired by an…

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…

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.

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 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.

The National frameworks for science emphasize inquiry skills (NRC, 1996), however, in typical classroom practice, science learning often focuses on rote learning in part because science process skills are difficult to assess (Fadel, Honey, & Pasnick, 2007) and rote knowledge is prioritized on high-stakes tests. Short answer assessments of…

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