Background information and procedures are provided for an experiment designed to introduce (1) crystal defects and their reactivity upon crystal dissolution; (2) hydrates electron and its reactivity; (3) application of radiochemical method of analysis; and (4) the technique of competitive kinetics. Suggested readings and additional experiments are…

Discusses a method for viewing the square of a curve directly. Results are seen immediately and the curve can be manipulated to show, for example, the continuous effect of changing the zero level. The method is useful in studying the effect of squaring a curve or waveform in optics/electronics courses. (JN)

Describes a course which emphasizes all facets of analytical chemistry, including sampling, preparation, interference removal, selection of methodology, measurement of a property, and calculation/interpretation of results. Includes special course features (such as cooperative agreement with an environmental protection center) and course…

Background information, laboratory procedures (including matings performed), and results are presented for an open-ended investigation using the fruitfly Drosophila melanogaster. Once data are collected, students develop hypotheses to explain results as well as devise additional experiments to test their hypotheses. Calculation of chi-square for…

Discusses development and presentation of a chemical demonstration show for grades 1-6 students. Includes major concepts presented and experiments used in the hour-long show. Concepts/experiments focus on the show's theme: the nature of chemical change. Safety factors involved when conducting demonstrations with children are addressed. (JN)

DTA is a technique in which the temperature difference between sample/reference is measured as a function of temperature, while both are subject to a controlled temperature program. Use of a simple DTA-apparatus in demonstrating catalytic effects of manganese dioxide and aluminum oxide on decomposition temperature of potassium chlorate is…

Compares two palladium (Pd/C) reducing systems to iron/tin-hydrochloric acid (Fe/HCl and Sn/HCl) reductions and suggests an efficient, clean, and inexpensive procedures for the conversion of nitrobenzene to aniline. Includes laboratory procedures used and discussion of typical results obtained. (JN)

Background information, apparatus, procedures, and typical results are provided for an experiment involving the direct synthesis of a phosphonium salt of the tetrachlorocobaltate(II) ion. A six-volt lantern battery supplies the necessary electric energy for the experiment. (SK)

Several simple experiments illustrating how the light regime affects the final form of dog's mercury (Mercurialis perennis) are provided. These experiments, which can also be done with other plants, focus on differences in the anatomy, morphology, and physiology of sun and shade leaves. (JN)

Reports design of an interactive computer program (FORTRAN) in microbial genetics. The program is divided into three stages: background information, simulation, and data treatment. Results obtained from the simulation allow four genes to be sequenced along the bacterial chromosome. The simulation mimics experimental errors and production of…

By using intense pulsed coherent x-ray sources it will be possible to obtain magnified three-dimensional images of living elementary biological structures at precisely defined instants. Discussed are sources/geometrics for x-ray holography, x-radiation interactions, factors affecting resolution, recording the hologram, high-intensity holography,…

The nature of liquid crystals and several important liquid crystal devices are described. Ideas for practical experiments to illustrate the properties of liquid crystals and their operation in devices are also described. (Author/JN)

Discusses a set of relations (addressing changes in volume and refractivity) for use in the study of binary systems. Suggests including such an experiment in undergraduate physical chemistry courses (measuring density/refractive index of pure compounds and their mixtures) to predict even small changes occurring during mixing process. (Author/JN)

Describes use of activation volumes derived from the effect of pressure reaction rates in aiding the understanding of reaction mechanism. Topics discussed include determination and interpretation of activation volumes, high pressure equipment/techniques, and application of activation volumes in mechanistic elucidation of several inorganic…

Although a large number of experiments on aquation kinetics of inert octahedral complexes exist, few exist on the reverse (anation) reaction. Preliminary considerations and laboratory procedures for a kinetic study of the anation reaction are provided. Several pairs of students can complete the experiment in a three-hour period. (Author/JN)