Discusses different existing definitions for the rate of reaction. Application to common reacting systems and to isothermal recycle reactors is also discussed. (HM)

Presents part two of an article that discusses the opinions of the public and scientists regarding Einstein and his theory of relativity during the years after 1919. (HM)

Investigates the level of students' understanding of the concept of evolution of natural selection. Sixty-three first year British university students with an advanced-level biology background participated in this study. (HM)

The difference between mass and weight is explained. The explanation is sophisticated, technical, and directed toward advanced technicians and scientific personnel. (MK)

Discusses electric and magnetic forces between parallel-wire conductors and derives, in a simple fashion, order of magnitude estimates of the ratio of the likely electrostatic and electromagnetic forces for a simple parallel-wire balance. (Author/HM)

Preservice physics teachers in a British university completed a word association test by supplying five physical quantities which they associated with a number of electromagnetic stimulus concepts. Gives analysis of concept linking as it may occur in the students' cognitive structures. (MLH)

Describes a quick, inexpensive laboratory demonstration of Charles's Law. The opening of a large, round balloon is placed snugly over the mouth of a narrow-mouthed 750-mL Erlenmeyer flask, which is then heated in a strong flame. At end of the full procedure, students easily arrive at the conclusion that the volume of a gas is proportional to…

Le Chbtelier's Principle states that, when a system at equilibrium is subjected to stress, the system will respond in such a way as to minimize the effect of the stress. Describes a lecture demonstration that illustrates shifts in the position of equilibrium caused by a variety of factors. The equilibrium mixture contains iron (III) and…

This pilot study of a project involving the design and making of a moisture sensor indicated that science knowledge developed through science lessons could not be used in technology lessons. This is argued to be because knowledge is constructed in the various contexts and hence not generalizable. Implications for science and technology teaching…

Describes three recent scientific theories (chaos theory, complexity theory, and fuzzy logic) and shows how they serve as metaphors for understanding English teaching. (SR)

States a convenient algorithm for temperature scale conversions and shows how performing the successive steps improves the accuracy of the results. (DDR)

Analyzes the effectiveness of introducing practical design projects at an early stage within a civil engineering undergraduate program. Traces the success of this strategy at each stage from its introduction to the final evaluation. Findings indicate that the projects were successful in improving the understanding of basic concepts and encouraging…

Describes an approach for making chemistry relevant to everyday life. Involves the study of kinetics using the decomposition of hydrogen peroxide by vegetable juices. Allows students to design and carry out experiments and then draw conclusions from their results. (JRH)

Describes the use of computer-based animations in demonstrating and enlivening scientific principles. Discusses frame-based animation, cel-based animation, object animation, the creation of simple animations, and the use of animation software. (JRH)

Discusses some of the conceptual difficulties encountered by undergraduate students in learning certain aspects of chemical equilibrium and thermodynamics. Discusses teaching strategies for dealing with these difficulties. (JRH)