Proposes a model for kinetic processes said to be similar in computational effort and yielding similar results to conventional transition state theory (TST), while maintaining parsimony and credulity. Argues that partitioning of states into groups be limited to energy space in contrast to TST. (JM)

Structural form, bonding scheme, and chromatin structure of and gene-modification experiments with deoxyribonucleic acid (DNA) are described. Indicates that DNA's double helix is variable and also flexible as it interacts with regulatory and other molecules to transfer hereditary messages. (DH)

Highlights five major analytical areas (electrophoresis, immunoassay, chromatographic separations, protein and DNA sequencing, and molecular structures determination) and discusses how analytical chemistry could further improve these techniques and thereby have a major impact on biotechnology. (JN)

Dynamic crystal model kits are described. Laboratory experiments in which students use these kits to build models have been extremely successful in providing them with an understanding of the three-dimensional structures of the common cubic unit cells as well as hexagonal and cubic closest-packing of spheres. (JN)

Describes a computer program that generates a random string of amino acids and guides the student in determining the correct sequence of a given protein by using experimental analytic data for that protein. (MLH)

Describes a simple method to determine potential chemical formulas for a given molecular weight and to calculate all of the typical mass spectrometric parameters which can be obtained experimentally. Calculated values can then be compared to experimental values to obtain the most reasonable formula. (JN)

Describes a physical chemistry experiment which uses group theory to help interpret the infrared spectrum of a polyatomic molecule with Td symmetry (spherical tops). Topics covered in the experiment: background information and theory, experimental procedures, and typical student results. (JN)

The RKR method for determining accurate potential energy curves is described. Advantages of using the method (compared to Morse procedure) and a TRS-80 computer program which calculates the classical turning points by an RKR method are also described. The computer program is available from the author upon request. (Author/JN)

Reactions of phenolphthalein with sodium hydroxide and sulfuric are discussed. Also discusses the sulfonation of phenolphthalein, listing experimental results related to the sulfonation reaction. (JN)

Provides background information, procedures, and results of an undergraduate physical chemistry experiment on the polarization of absorption spectra of cyanine dyes in stretched polyvinyl alcohol films. The experiment gives a simple demonstration of the concept of linear dichromism and the validity of the TEM method used in the analyses. (JN)

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)

Describes the discovery, physical properties, and future applications of liquid crystals. (SK)

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.…

Describes an experiment in which parameters from an "ab-initio" potential are used to calculate vibrational-rotational energy levels and construct a "stick spectrum" for the overtone emission of the hydroxyl radical. Provides background information on ab-initio spectrum, experimental procedures, and analysis of data. (Author/JN)

Supplies information to answer typical student questions relating to the significance of "plus" and "minus" superscripts used for electronic states of linear molecules. (SK)