A cost-analysis competition was introduced into the experimental synthesis sequence of an organic chemistry course. Rationale for the approach as well as experiments involved are discussed. (JN)

Discusses the values presented in various handbooks for the boiling point and heat of vaporization of sulfuric acid, noting discrepencies. Analyzes various approaches to data presentation, discussing the data on sulfuric acid in light of the Trouton constant. Points out the need for a more critical use of tables. (JM)

Describes a procedure for the qualitative analysis of aluminum subgroup cations designed to avoid failure to obtain lead or barium chromate precipitates or failure to report aluminum hydroxide when present (due to staining). Provides a flow chart and step-by-step explanation for the new procedure, indicating significantly improved student results.…

Describes an experiment on the simultaneous determination of chromium and magnesium by spectophotometry modified to include the Generalized Standard Addition Method computer program, a multivariate calibration method that provides optimal multicomponent analysis in the presence of interference and matrix effects. Provides instructions for…

Describes two computer programs for use in process design courses: an easy-to-use equipment cost estimation program based on latest cost correlations available and an economic evaluation program which calculates two profitability indices. Comparisons between programed and hand-calculated results are included. (JM)

Describes a microscale laboratory course in which students perform many classic organic reactions using only one-hundredth to one-thousandth the amount of starting material usual in student experiments. Reduction of toxic chemicals concentration in laboratory air and savings in chemical costs and experimental time are benefits of the novel course.…

This article contains suggestions for introducing the scientific concept of matter and demonstration acids and bases using low-cost, collectible supplies. Sample questions and experiments are listed to help students explore these ideas. A list of household supplies to be used in the experiments is given. (DF)

Background information (including optical properties of inorganic materials) and procedures are provided for an experiment which introduces students to preparation of a doped semiconductor; phosphorescence; gettering procedures; reducing atmospheres; and use of a high-temperature furnace with associated thermocouples, temperature controllers, and…

Classifies several kinds of readily available foreign language computer programs. Most of the programs fall into either game/activity or testing categories. In all the programs, feedback to the student who has made an error is limited. Sees the computer as a specific information resource in self-directed learning programs. (SED)

Examines techniques used to make ultrasensitive spectroscopic measurements. They include excitation, thermal lens, photo acoustic, and ionization spectroscopies. Guidelines and methods are provided for each technique; common uses and applications are explained. (DH)

Describes an apparatus developed for photochemical studies, particularly those involving the fluorescence of halogenated acetones. The apparatus is constructed from equipment normally found in a moderately sized physical chemical laboratory. Also provides background information on some aspects of the photophysics of halogenated propanones. (JN)

Describes a set of experiments (for senior-level biochemistry students) which permit evaluation and estimation of rate and equilibrium constants involving an intermediate in the alpha-chymotrypsin mediated hydrolysis of ortho-hydroxy-alpha-toluenesulfonic acid (I). The only equipment required for the experiments is a well-thermostated double beam…

The advantages of DNA hybridization procedures for classroom and clinical use can now be realized by the recent development of nonradioactive DNA labeling/detection procedures. These methods (which are described) can replace the use of isotopes in standard DNA hybridization procedures. (JN)

Traces the history of using mice for medical research and discusses the benefits of using these animals for studies in bacteriology, virology, genetics (considering X-linked genetic homologies between mice and humans), molecular biology, immunology, hematology, immune response disorders, oncology, radiobiology, pharmacology, behavior genetics,…

Suggests a simple technique for collecting and observing human hair roots to compare structure, function, and variation. Students extract their own hair samples and view them using a 40-power microscope objective. Differences between active/inactive phases of hair growth are readily observed. (The activity can be adapted for younger students.) (DH)