Several chemical concepts can be visualized by using deformation density maps. They often present convincing experimental confirmation and they should be incorporated into the chemistry curriculum dealing with bonding and molecular structure. Examples of the maps and quantitative information derived from research studies are presented. (JN)

Compares linear-nonlinear and planar-nonplanar geometry through the valence-shell electron pairs repulsion (V.S.E.P.R.), Mulliken-Walsh, and electrostatic force theories. Indicates that although the V.S.E.P.R. theory has more advantages for elementary courses, an explanation of the best features of the different theories offers students a better…

Assigning "R" or "S" descriptors to chiral centers by inspection of a stereoformula often results in mistakes, especially when three-dimensional representations (with solid and dashed bonds for substituents pointing to front or rear) are used. Therefore, a method is presented that can be applied to all three-dimensional…

After noting the grounds for labelling structures as incorrect, the guidelines for selecting which Lewis structures are most important for a molecule are introduced. Several examples of appropriate Lewis structures and the fine structural predictions that are possible are included. (JN)

Discusses various ethylenediaminetetraacetate (EDTA)-type chelating agents found in ophthalmic products, personal care products, and disinfectants. Also discusses the properties and action of these EDTA agents. (JN)

Discusses reactions of free radicals that determine the chemistry of many fresh, processed, and stored foods. Focuses on reactions involving ascorbic acid, myoglobin, and palmitate radicals as representative radicals derived from a vitamin, metallo-protein, and saturated lipid. Basic concepts related to free radical structure, formation, and…

Discusses the contributions of G. N. Lewis to chemistry, focusing on his formulation of the basic principle of the chemical bond--the idea that the chemical bond consists of a pair of electrons held jointly by two atoms. (JN)

Discusses matrices of the common coupling cases and molecular formation according to models based on union of separate species, description of the united atom, and electron configuration. The matrix tabulations reveal general patterns which make extrapolations easy without detailed use of the Wigner Witmer rules. (JN)

Since the usefulness of cyclic point groups is oftentimes neglected in textbooks, suggestions are given for writing down tables of characteristics for these groups. (SK)

Describes the initial site, and symptoms of the human immunodeficiency virus. Explains the diverse behavior and destructive consequences of the disease through discussion, diagrams, and pictures of the life cycle of the virus and the genetic material that controls it. (RT)

Describes a method that uses ping-pong balls to construct 3-D models of covalent molecules to represent Group I-VIII atoms. (ZWH)

Evaluates first-year college students' perceptions of molecular modeling. Examines the effectiveness, integration with course content, interests, benefits, advantages, and disadvantages of molecular modeling. (Author/CCM)

Green chemistry is the awareness of the damaging environmental effects due to chemical research and inventions. There is emphasis on a need to include green chemistry in synthesis with atom economy in organic chemistry curriculum to ensure an environmentally conscious future generation of chemists, policy makers, health professionals and business…

Conformational analysis of cyclohexanes is a fundamental, requisite topic covered in undergraduate organic chemistry. A molecular modeling experiment is designed with the view of extending students' boundaries of knowledge about cyclohexane conformational stabilities.

A comprehensive theoretical description of thermal protein unfolding coupled to ligand binding is presented. The thermodynamic concepts are independent of the method used to monitor protein unfolding but a differential scanning calorimetry is being used as a tool for examining the unfolding process.