Describes an electrode, selective for the salicylate ion, that can be prepared and used by undergraduate students. Discusses the preparation of the electrode, typical response characteristics obtained, and results of a limited study using the electrode to estimate the selectivity coefficient for an interfering ion and to determine the amount of…

Presents an experimental approach to illustrate that the thermodynamic properties of a system can be considered as the average of mechanical variables. Discusses the Knudsen effusion method to count the number of molecules, vapor pressure, the piezoelectric effect, the experimental setup, and sample experimental results. (JRH)

Provides an alternative method to test for vitamin C. Uses starch-iodine in place of DCPIP as the reagent in this experiment. (YDS)

Presents an activity to determine whether the radioactivity of a pure potassium salt is directly proportional to the amount of potassium in it and whether this could be used as a method of analysis for potassium in a solid. (MKR)

Presents experiments that use Helmholtz resonators and have been designed for a sophomore-level course in oscillations and waves. Discusses the theory of the Helmholtz resonator and resonance curves. (JRH)

Describes how burying beetles can be used to explore conflicts between breeding individuals. Discusses conflict over the ownership of the resource and of the breeding group. (JRH)

Describes a laboratory exercise used by botany students to verify their textbook's teaching about photosynthesis and respiration. (ZWH)

Describes an inexpensive replacement for the gel matrix, agarose, to aid teachers in reducing the cost of supplies needed to perform gel electrophoresis experiments. (ZWH)

This experiment subjects bacteria in a food sample and an environmental sample to conditions of sublethal stress in order to assess the effectiveness of the agar overlay method to recover sublethally injured cells compared to direct plating onto the appropriate selective medium. (SAH)

Describes the construction and use of an inexpensive colorimeter that reliably estimates the phosphorus concentrations in water. Presents a two-step modification to an existing photometer. (SAH)

Describes a simple way for groups to view a demonstration of Brownian Motion using a laser and liquid suspension. (AIM)

Describes a laboratory course that introduces students to chemistry using examples commonly encountered in the supermarket and on the dinner table. Acquaints students with simple chemical tasks that can be practiced at home, including the making of wine, ale, soap, cheese, and yogurt, and introduces them to the small-scale production of…

Describes a combination of solutions that can be used in the study of kinetics using the iodine clock reaction. The combination slows down degradation of the prepared solutions and can be used successfully for several weeks. (JRH)

Discusses some of the important characteristics of fungi. Presents exercises designed to introduce students to factors influencing the development of mushroom fruiting bodies. (JRH)

Discusses the behavior of the current near the end of the paper in the electric-field mapping experiment and approaches to solving problems associated with this behavior. Presents programs that can be used to model the boundary condition computationally. (JRH)