Presents a modification of the classic Blue Bottle demonstration that involves the alkaline glucose reduction of methylene blue. Uses other indicators in the classic Blue Bottle to produce a rainbow of colors. (JRH)

Discusses flaws in the reasoning behind a "new system" proposed for rounding numbers that was published in a previous issue of this journal. Concludes that the new system should be used only for numbers in which the nonzero digits following a dropped 5 have some significance. (JRH)

Describes a simple audio conductivity device built to address the problem of the lack of sensitivity needed to measure small differences in conductivity in crude conductivity devices. Uses a 9-V battery as a power supply and allows the relative resistance differences between substances to be detected by the frequency of its audible tones. Presents…

Describes CIRRUS (the Chemistry Internet Resource for Research by Undergraduate Students), an Internet-based resource in support of the undergraduate chemical research enterprise. Supports communication and information-sharing by providing a companion electronic mail server. Presents examples of services provided by CIRRUS. (JRH)

Describes the Science ExpOlympics, an outreach program of competitive and noncompetitive events for high school students. Involves competitive activities, activities and demonstrations, and a science bowl competition for regional high school students. Lists events taking place at the Science ExpOlympics. (JRH)

Offers a scientist's perspective on reshaping the teaching of science. Topics include defining science--science is a dynamic process with no absolutes; scientific truth--science never stands still; and science, sense-experience, and reality. Contains 26 references. (JRH)

Discusses reasons why students find chemistry abstract and difficult. Highlights the fact that there has been very little change in the general chemistry course or in the textbooks. Argues in favor of the need for a new textbook that can influence enough teachers to change. Presents suggestions for future textbook authors. (JRH)

Discusses the problem of the inherent instability of paper due to the presence of acids that catalyze the hydrolytic degradation of cellulose. Focuses on the chemistry involved in the sizing of both acid and alkaline papers and the types of fillers used. Discusses advantages and problems of alkaline papermaking. Contains 48 references. (JRH)

Describes one teacher's implementation of portfolio assessment in high school chemistry classrooms in an effort to hold students accountable for more than mere factual recall and to involve students proactively in the assessment process. Discusses the setting, the portfolio, evaluation, and outcomes. (JRH)

Presents an activity designed to increase students awareness of the relevance of science. Involves a classroom jury trial to probe a current controversial drug, mifepristone (RU486). Reports that students perceived this to be an enjoyable as well as educational activity which made science more relevant in their lives. (JRH)

Analyzes the algebraic method for balancing chemical reactions. Introduces a third general condition that involves a balance between the total amount of oxidation and reduction. Requires the specification of oxidation states for all elements throughout the reaction. Describes the general conditions, the mathematical treatment, redox reactions, and…

Presents activities that involve the separation and identification of dyes from mouthwashes and the determination of their alcohol content. Provides a review of various analytical techniques and shows students that more than one instrument or technique may be required to analyze a product. (JRH)

Presents experiments that introduce students to the myriad properties of zeolites using the sodium form of zeolite A (Na-A) from laundry detergent. Experiments include extracting Na-A from detergent, water softening properties, desiccant properties, ion-exchange properties, and Zeolite HA as a dehydration catalyst. (JRH)

Describes the design and construction of a safe student quantitative conductivity apparatus. Discusses experimental results. (JRH)

Describes an apparatus that is stable and accurate enough for quantitative conductivity experiments but maintains the simplicity of construction and use as well as low cost. Discusses principles and implementation and the performance of the assembled apparatus. (JRH)