Investigated use of overhead transparencies containing a sequence of diagrams to represent a three-dimensional structure at different stages during a rotation. Significant learning occurred among 120 Bahraini boys (aged 15-16) when the transparencies contained multi-colored diagrams which were exposed simultaneously or individually in a cumulative…

Advocates the teaching of quantum chemical ideas to undergraduates. Discusses the total failure of the electronegativity approach and comparison with other theoretical approaches. (CW)

Describes a simple method to teach molecular geometry using styrofoam balls and velcro strips. Discusses the construction and a procedure for using the model for teaching. (CW)

The pencil-and-paper assignment "Represent water in its three states using a model" was given to pupils (n=227) from eighth to twelfth grades. The findings show that the dominant model used was the space filling type; movement of particles was indicated by a minority of pupils; size of the model changed when drawn in different states.…

Gives the background history of the simultaneous discovery of acid-base relationships by Johannes Bronsted and Thomas Lowry. Provides a brief biographical sketch of each. Discusses their concept of acids and bases in some detail. (CW)

Reports on a study into the relationship between a student's ability to solve problems in chemistry and his/her understanding of molecular concepts. Argues that teaching students to solve problems about chemistry is not equivalent to teaching about the nature of matter. (TW)

Described is a method that can be used to obtain molecular or atomic term symbols. Several examples accompany an explanation of the method. (CW)

Presented is a comprehensible structural representation of humic substances. A number of important roles of soil organic matter, including contribution to the cation-exchange capacity, binding of pesticides, and formation of complexes with micronutrient cations, are illustrated. (Author/CW)