Two experiments are presented which help to illustrate a modular approach to electrochemical instrument design, but which are readily understandable to students with a limited electronics background. The experiments are coulometric titration and controlled potential coulometry.

Describes the use of benzophenone in the role of a solid state sensitizer in a photochemical isomerization and as an indicator in preparative layer chromatography for purification of the isomeride. (Author/SA)

Presents an improved technique for synthesizing acetanilide from nitrobenzene by reducing nitrobenzene with iron powder and hydrochloric acid. This experiment has been used successfully with 2,000 students during two semesters. (Author/SA)

Discusses the impact of using laboratory exercises and queries on developing student sensitivity to bioethical issues. Examples of these questions and the responses of students of an introductory life science course at Worcester Polytechnic Institute, Worcester, Massachusetts are presented. (HM)

Describes a laboratory experiment which demonstrates manipulation of highly reactive chemicals, use of a gas trap, and simple and reduced pressure distillation. Student must characterize starting material and product with nuclear magnetic resonance and infrared spectroscopy. (Author/SA)

Presents information intended to encourage students to become thoughtful consumers. Discusses the role of pepsin in splitting off amino acids from stomach proteins and the nature of the protein substrate in determining the ph at which pepsin operates. Directions for an experiment are included. (Author/SA)

Presents an experiment for inorganic, organic, or physical chemistry students utilizing acid-base titrimetry to study the stoichiometric of a solid state reaction. Time involved ranges from one to three, three-hour lab periods. (Author/SA)

Describes three college lab exercises which can be used to demonstrate the elements and characteristics of continuous flow injection analysis. (HM)

Reviews studies of regulation of nasal airway resistance (Rn). Describes methods of calculating Rn by measuring pressure-flow relationship. Data are presented on improved methods for measuring Rn and effects for expiratory and inspiratory Rn after topical application of phenylephrine nasal decongestant spray. (Author/SA)

Presents a reliable method for the sterilization of ciliates using common lab equipment and skills. A modified Glaser and Coria technique is used. (MA)

This method uses the cathodic deposition of silver from a cyanide solution in a non-partition cell with stainless steel electrodes. (BB)

Describes a simple method of measuring the refractive index of a liquid using a paper cup, a liquid, a pencil, and a ruler. Uses the ratio between the actual depth and the apparent depth of the cup to calculate the refractive index. (GA)

Various approaches to the standardization of pH meters are compared and the limitations of each are pointed out. (BB)

Describes some laboratory exercises using the mole crab, Emerita talpoida, as an experimental animal for the study of osmoregulation. (GA)

Explains how to demonstrate the following: the hysteresis effect and the existence of domains in Rochelle salt (sodium potassium tartrate); diffraction experiments using a slide with multiple slits; and an analogue technique for learning terminal velocity. (GA)