Describes a demonstration in which gaseous ammonia and hydrochloric acid are used to illustrate rates of diffusion (Graham's Law). Simple equipment needed for the demonstration include a long tube, rubber stoppes, and cotton. Two related demonstrations are also explained. (DH)

Describes hardware and software requirements for interfacing a thermometer probe, via an analog and digital converter, to any Commodore PET, VIC-20, or Commodore-64 microcomputer (or other microcomputers with some modifications). Also describes use of the probe in an experiment measuring enthalpies of reaction to determine enthalpy of formation of…

Discusses various aspects of space astronomy, considering advantages, the space telescope and ground-based astronomy, an orbiting astrophysics facility, solar physics, and other areas. Indicates that earth-based astronomy will continue to be carried out there and space astronomy will be limited to observations that can be carried out only from…

Presents excerpts of a survey on the instrument status in chemistry departments and the perceived needs of those departments for new instruments. Responses are based on data from 32 chemistry departments at major research institutions, 71 departments at smaller schools, and 13 chemical engineering departments. (JN)

The three principal commercially published science projects for less able/motivated students include units on electronics. A simple and inexpensive method of constructing electric circuits is described. Suggestions for making the material in the published units applicable to circuits found in everyday situations are offered. (JN)

Presents 23 experiments, activities, field projects and computer programs in the biological and physical sciences. Instructional procedures, experimental designs, materials, and background information are suggested. Topics include fluid mechanics, electricity, crystals, arthropods, limpets, acid neutralization, and software evaluation. (ML)

Procedures for displaying computer-generated text and graphics to a large audience are inexpensive when a Fresnel-mirror projector is used. Although small liquid-crystal displays (LCDs) can be easily projected, large LCDs require some modification (which is described). Other devices with LCD displays (oscilloscopes, televisions, and pulse-height…

Reviews three functions performed by modern computing integrators: (1) data acquisition; (2) data processing; and (3) communication. Also shows with examples how new electronic components enhance the functions of this popular analytical instrument in those areas. (JN)

Shows how an electric stud finder (available from hardware stores for $15-20) is used to detect changes in capacitance produced by changes in thickness of a medium or in dielectric constant. Also describes how to construct an inexpensive motor from a battery, rubber bands, ceramic magnet, and copper wire. (DH)

Describes these tools for physics teaching: (1) stick with calibrations for measuring student reaction time; (2) compact high-pressure sodium lamps used to demonstrate spectra; (3) air pumps for fish tanks providing simple inexpensive motors; (4) a rotating manometer for measuring centripetal force; and (5) an apparatus for checking conservation…

Provides directions for setup and performance of two demonstrations. The first demonstrates the principles of Raoult's Law; using a simple apparatus designed to measure vapor pressure. The second illustrates the energy available from alcohol combustion (includes safety precautions) using an alcohol-fueled missile. (JM)

Describes a comprehensive nuclear magnetic resonance (NMR) experiment designed to introduce undergraduate organic chemistry students to measurement/interpretation of NMR parameters. Students investigate chemical shift analysis, spin-spin coupling, peak integrations, effect of deuterium oxide extraction, and comparisons with literature spectra;…

Discusses the culturing of microorganisms as a laboratory activity emphaszing the growth of microorganisms in food. Provides background and safety information, procedures, and additional ideas. The complete unit (teacher's guide, student worksheets, evaluation and assessment, and resources for students and teachers) is available from the author.…

Discusses using Apple II microcomputers for measuring resistance, temperature, and light intensity. Also discusses digital input and output and timing techniques. Although focusing on Apple II, the circuits and programs described may be applicable to other microcomputers. (JN)

Describes the procedures and equipment for an experiment on the adiabatic expansion of gases suitable for demonstration and discussion in the physical chemical laboratory. The expansion produced shows how the process can change temperature and still return to a different location on an isotherm. (JN)