One undergraduate chemistry laboratory at the California Institute of Technology is described, including goals of the laboratory curriculum: (1) emphasis on modern instrumental methods of analysis, separation, and characterization; (2) integration of organic/inorganic experiments; and (3) preparing students in two years to begin work in a research…

Procedures are outlined for a laboratory exercise in which students use a gravimetric method to determine the rate of transpiration in sunflower seedlings. Discusses the data in terms of the effectiveness of stomatal openings, mechanisms for water movement in plants, and the role of transpiration in the environment. (DC)

Cathodoluminescence is visible light emitted from a specimen when it is bombarded with electrons. A technique known as cathodoluminescence petrography can provide information especially useful in studies or courses related to mineralogy and petrology. The technique is briefly presented, along with examples to illustrate typical results. (Author/WB)

A simple isotonic, dilution analysis whose principles apply to methods of more complex radioanalyses is described. Suitable for clinical and instrumental analysis chemistry students, experimental manipulations are kept to a minimum involving only aqueous extraction before counting. Background information, procedures, and results are discussed.…

Products of nitrations, upon distillation or steam distillation, may produce dermatitis in some students. A procedure for nitration of beta-naphthol producing a relatively non-volatile product not purified by steam distillation is described. Nitration of alpha-naphthol by the same procedure yields Martius Yellow dye which dyes wool yellow or…

Reports an oxidation-reduction experiment using tungsten, somewhat analogous to the classical student experiment involving oxidation-reduction of vanadium. Includes experimental procedures, results, and toxicity/cost of tungsten compounds. (Author/JN)

Reports on the conversion 2,5-dimethylhexyne-2,5-diol(I) to 2,2,5,5-tetramethyltetrahydrofuran-3-one(II) using aqueous mercuric sulfate without the use of acid. The experiment has been successfully performed in introductory organic chemistry laboratories demonstrating alkyne hydration, steam distillation, vacuum distillation, drying of organic…

Outlines 2 procedures for synthesizing 2-acetyl-1,4-naphthoquinone to compare relative merits of the two pathways. The major objective of the exercise is to demonstrate that certain factors should be considered when selecting a pathway for synthesis including availability of starting materials, cost of reagents, number of steps involved,…

Background information and experimental procedures are provided for a Prins reaction (condensation of an aldehyde with an alkene). The preparation of 4-(4-hydroxy, 3-methoxy-phenyl) 5-methyl, 1,3-dioxane realized from isoeugenol (natural plant product, commercially available) can be completed in a three-hour laboratory period. (Author/JN)

Describes a simple, three-step synthesis of two cage molecules, birdcage hydrocarbon (VIII) and its homologue, the homobirdcage hydrocarbon IX. Indicates that all products are easily purified and formed in high yields in this activity suitable for advanced undergraduate laboratory courses. (Author/JN)

Ten questions regarding classroom and shop safety are presented for the teacher and school administrator to test themselves and guard against a ruling of negligence and legal liability in the performance of their jobs. (CT)

The Consumer Product Safety Commission will recommend an information network to inform students and teachers of current toxicity evaluations of chemicals and of possible use of less hazardous substitutes. Lists names of 33 suspected carcinogens and 11 suspected teratogens. (SK)

Presents three reports: a description for an upper-level course in protein chemistry; a technique for generating many unique unknowns for the determination of molecular weight by viscosity; and an analogy for quantization of energy levels in which molecules are considered as books in a library. (CS)

A new method of carrying out grafts of early embryonic chick limb buds to the chick chorio-allantoic membrane and a processing schedule which renders cartilage elements visible in whole mount are discussed, including implications for the procedures and their results. (Author/DC)

A technician auto analyzer (consisting of six modules: sampler, multichannel peristaltic pump, dialyser, heating/incubation bath, colorimeter, and recorder) was modified by using key modules and substituting standard equipment for others; spectronic 20 with homemade flow cell for colorimeter module. Descriptions and diagrams of the apparatus are…