The assembly and use of an Ostwald-type of viscometer from readily available materials is illustrated. Sample data and a schematic of the apparatus are provided. (CW)

Describes three demonstrations showing chaotic motion, which makes long-term prediction impossible. Discusses the apparatus for the demonstrations and procedures for illustrating chaotic motion of pendulum, balls rolling in a double potential well, and a ball rolling on a balanced beam. (YP)

Describes science activities which use simple chemical tests to distinguish between materials and to determine some of their properties. Explains the water, iodine, heat, acid, baking soda, acid/base indicator, glucose, and sugar tests. Includes activities to enhance chemical testing and a list of suggested powders for use. (RT)

Presents an exercise which was designed to help students read material and follow directions more appropriately when performing laboratory activities. Provides a list of materials, instructions, comments, vocabulary words, and a diagrammatical sketch of an insect. (RT)

Provides the methodology put forth by Moore and Kraus to separate Co++ from Ni++ in an 8M HCl solution. Notes that cobalt(II) forms a wide variety of anionic complexes. Points out that as the solutions leave the exchange column the color bands of green, blue, and pink are easily seen. (MVL)

Reviewed is some of the experimental evidence for apostatic selection from work with artificial prey. Guidelines for further experiments are suggested including experimental design, analysis, variables, and selection in the wild. (Author/CW)

Provides a set of guidelines for infection control of the Acquired Immune Deficiency Syndrome and the serum hepatitis viruses during blood typing procedures. Emphasizes that disposal of blood contaminated materials should comply with local health department recommendations. (RT)

Presents a method which introduces biology students to some fundamental aspects of scientific methodology. Explains simple muscle testing procedures, a historical perspective, experimental variables, pedagogical uses, and possible mechanisms of the muscle response phenomenon action. (RT)

Describes an advanced NMR project that can be done with a 60-MHz continuous-wave proton spectrometer. Points out the main purposes are to give students experience in second-order NMR analysis, the simplification of spectra by raising the frequency, and the effect of non-hydrogen nuclei on proton resonances. (MVL)

Presents a procedure used in sophomore level organic chemistry which has been particularly useful for organic qualitative analysis. Uses a nine-well spotplate and one-two mg of solid and three-four drops of eight different solvents. Solubility is checked at different temperatures. Provides a solubility table. (MVL)

Describes an experiment to determine the density of air within a 10 percent error range using a basketball and a triple beam balance. Provides the typical data and a graph. (YP)

The ideas behind electrophilic addition to alkenes, and electrophilic substitution in benzene derivatives are discussed. Teaching these concepts to secondary school students is stressed. Five main points useful at this age level are summarized. (Author/CW)

Describes three demonstrations: (1) "A 'Rocket' Cart" (using a fire extinguisher and a child's truck); (2) "Angular Momentum Conservation" (providing materials and calculations); and (3) "Cavendish Experiment" (including the building method and examples of calculations). (YP)

Discusses the calculation of free energy in reactions between silicon dioxide and carbon. Describes several computer programs for calculating the free energy minimization and their uses in chemistry classrooms. Lists 16 references. (YP)

Describes a method for using nuclear magnetic resonance to observe the effect of electronegativity on the chemical shift of protons in similar compounds. Suggests the use of 1,3-dihalopropanes as samples. Includes sample questions. (MVL)