The purpose of this study was twofold: (1) to understand the conceptual frameworks that sixth-grade students use to explain the nature and structure of matter and molecules; and (2) to assess the effectiveness of two alternate instructional units in helping students change those conceptions. The study involved 15 sixth-grade classes taught by 12…

Describes two secondary-level classroom games designed to teach the balancing of chemical equations and the principles of chemical bonding. (MLH)

Differentiates between chemical nomenclature and the common ways that substances are named and described. Students should learn the chemical nomenclature so that they will be more observant and objective. Cites examples of student misconceptions based upon their own imagination and logic. (TW)

Discusses the production and use of polymer materials as thermal insulators. Lists several materials that provide varying degrees of insulation. Describes the production of polymer foam and focuses on the major applications of polystyrene foam, polyurethane foam, and polyisocyanurate foam. (TW)

Discusses electron-loss spectroscopy and the experimentally observed excitation energies in terms of qualitative MO theory. Reviews information on photoelectron spectroscopy and electron transmission spectroscopy and their relation to the occupied and unoccupied orbital levels. Focuses on teaching applications. (ML)

Outlines a multistep project involving oxidation of cholesterol, isomerization of an enone, and reduction of delta-4-cholesten-3-one. Featured is the last stage in which the ring junction is set stereospecifically. Recommends two laboratory periods to complete the reaction. (ML)

Describes two introductory exercises designed to teach the fundamental ideas and methods of crystallography, and to convey some important features of inorganic and organic crystal structures to students in an advanced laboratory course. Exercises include "The Crystal Structure of NiO" and "The Crystal Structure of Beta-Fumaric Acid." (CW)

Discusses advantages of nematode use for studying patterns of cell division, differentiation, and morphogenesis. Describes nematode development. Cites experimental approaches available for genetic studies. Reviews the topics of control of cell division and differentiation, the nervous system, and muscle assembly and function of the organism. (RT)

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)

Describes a visual transparency method to develop the concept of resonance with respect to molecular resonance hybrid structures and partial charge on the atoms of an ion. Discusses the distinction between tautomerism and resonance, and emphasizes clarification of the Lewis structure concept. (JM)

Describes: (1) an interactive computer simulation for a science fair display of chromatography inks; (2) analytical chemistry programs; (3) microcomputer-assisted drills in organic synthesis; (4) programs for conformation analysis of ethane and butane; (5) MOLPIX--a program for generating and displaying molecular structures; and (6) chemical…

Describes a series of experiments (intended to approximate the research experience) investigating the reaction of ferrocenylmethylation with aniline. Students carry out reactions in nitrogen atmosphere, identify products by nuclear magnetic resonance spectroscopy and propose mechanisms and structures for reactions. Gives procedures for each…

Background information, procedures, and typical results are provided for a three-part experiment involving reactions of potassium thiocynate (KNCS) with sulfuric acid. The experiment represents the final stage of structured work prior to students' research projects during their final year. (JM)

This study investigated how students develop their understanding of chemical representations with the aid of a visualizing tool, eChem, that allows them to build molecular models and simultaneously view multiple representations. Multiple sources of data were collected with the participation of high school students (n=71) over a six-week period.…

Background information and procedures are provided for an experiment to prepare three metal derivatives of dimethyl sulfoxide (DMSO) and to determine some structural features of these derivatives based on their infrared spectra. Results and discussion of reactions involved are also provided. (JN)