A molecular approach for introducing entropy in undergraduate physical chemistry course and incorporating the features of Davies' treatment that meets the needs of the students but ignores the complexities of statistics and upgrades the qualitative, intuitive approach of Lambert for general chemistry to a semiquantitative treatment using Boltzmann…

The computer systems available for molecular modeling are described, along with a discussion of a molecular modeling program created and supported by computational techniques for the first-semester general chemistry course. Various exercises are listed, which direct the learner from a beginner's course in software practice to more complex…

The origins of the pion exchange model of nuclear forces are described and the exchange process is reinterpreted in the light of current views on the quark-gluon structure of nucleons. It is suggested that the reinterpretation might provide a picture of cohesive nuclear forces that is more intellectually satisfying than that produced by the…

A laboratory experiment is presented for the upper-level undergraduate physical chemistry curriculum in which the ternary phase diagram of water, 1-propanol and n-heptane is measured using proton nuclear magnetic resonance (NMR) spectroscopy. The experiment builds upon basic concepts of NMR spectral analysis, typically taught in the undergraduate…

The kinetics experiments on the ligand-C[subscript 60] exchange reactions on (dihapto-[60]fullerene) pentacarbonyl tungsten(0), ([eta][superscript 2]-C[subscript 60])W(CO)[subscript 5], form an educational activity for the inorganic chemistry laboratory that promotes graphical thinking as well as the understanding of kinetics, mechanisms, and the…

Describes a procedure for teaching the "generator orbital" (GO) approach of molecular orbital bonding in polyatomic molecules. Explains how the GO can be utilized with students in generating the vibrational, rotational, and translational modes of molecules in a completely pictorial manner. (ML)

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…

This short article consists of some thoughts derived from a longer paper (Palmer, 1992), together with some more recent ideas. I became interested in buckminsterfullerene (Buckyballs) as a result of an E-Mail discussion of the topic in 1991. The chemistry of buckyballs is now evolving very rapidly and is gradually creeping into school…

Understanding the structure and function of proteins is an important part of the standards-based science curriculum. Proteins serve vital roles within the cell and malfunctions in protein self assembly are implicated in degenerative diseases. Experience indicates that this topic is a difficult one for many students. We have found that the concept…

Provides background material which relates to the concept of activation energy, fundamental in the study of chemical kinetics. Compares the related concepts of the Arrhenius activation energy, the activation energy at absolute zero, the enthalpy of activation, and the threshold energy. (CS)

Thermochemical cycles are used to decide which hypothetical compounds might exist and, if not, what is the factor that condemns them to non-existence. Hypothetical compounds of rare gases provide examples of the approach with added historical interest that thermochemical considerations led to prediction and demonstration that XePtF-6 was stable.…

Expands the basic concepts regarding the radiation chemistry of simple aqueous systems to more complex, but well defined, organized assemblies. Discusses the differences in behavior in comparison to simple systems. Reviews these techniques: pulse radiolysis, laser flash, photolysis, and steady state irradiation by gamma rays or light. (CS)

Describes a three-dimensional computer modeling system for biological molecules which is suitable for sixth-form teaching. Consists of the modeling program "RasMol" together with structure files of proteins, DNA, and small biological molecules. Describes how the whole system can be downloaded from various sites on the Internet.…

Discussed are the molecular electronic terms which can arise from a given electronic configuration. Considered are simple cases, molecular states, direct products, closed shells, and open shells. Two examples are provided. (CW)

The study examines the effectiveness of visually enhanced instruction that emphasizes molecular representations. Instructional conditions were specified in terms of the visual elaboration level (static and dynamic) and the presentation mode (whole class and individual). Fifty-two eighth graders (age range 14-15 years) participated in one of the…