Develops an experiment that could be done in two- to three-hour blocks and does not rely on cold room procedures for most of the purification. Describes the materials, methods, and results of the purification of bovine heart lactate dehydrogenase using ammonium sulfate fractionation, dialysis, and separation using affinity chromatography and…

Described is a lesson in which the midpoint of the measuring stick (center of gravity), the balance point of the stick (fulcrum) and the arithmetic mean are assumed to be the same point. Provides content background, lesson outline, procedure, evaluation, teacher notes, and diagrammatical representations. (RT)

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)

Describes a chemistry club project. Explains the three goals: to enhance hands-on science in elementary classrooms, to encourage females to enter the field of science, and to encourage high school students to consider teaching as a career choice. Provides an outline and examples of the characters and demonstrations. (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)

Describes a variety of approaches for forming partnerships among high schools, universities, and industries for solving the problems that face precollege science education. (YP)

Discusses three broad classes of magnetic behavior: diamagnetic, paramagnetic, and ferromagnetic. Presents a simple lecture demonstration using an overhead projector to synthesize triiron tetraoxide and to show its interaction with a magnetic field and comparing it to a paramagnetic material. (MVL)

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)

Explains the operation of five relative humidity sensors: psychrometer, hair hygrometer, resistance hygrometer, capacitance hygrometer, and resistance-capacitance hygrometer. Outlines the theory behind the electronic sensors and gives computer interfacing information. Lists sensor responses for calibration. (MVL)

Discusses a laboratory technique of enzyme purification by affinity chromatography as part of an undergraduate biochemical methodology course. Provides preparation details of the rat muscle homogenate and reagents. Proposes column requirements and assaying information. (MVL)

Describes a laboratory technique for quantitative analysis of caffeine by an isotopic dilution method for coupled gas chromatography-mass spectroscopy. Discusses caffeine analysis and experimental methodology. Lists sample caffeine concentrations found in common products. (MVL)