This demonstration, if done in the original way, can lead to fires in waste containers (sometimes in the middle of the night after the experiment has been conducted), because pyrophoric zinc is generated by suspending powdered zinc in hot sodium hydroxide. This is avoided by using hot ZnSO[subscript 4].

To visualize what takes place in a chromatography column, enlarge the molecules to human size and expand the columns to keep the ratio of size of molecule to size of column the same. If we were molecules, what would the columns be like? A typical gas chromatography (GC) capillary column would be 50 x 10 [superscript 6] 6 km (31 million mi) long,…

In this article we examine three approaches, leading to different conclusions, for answering the question "Does the addition of inert gases at constant volume and temperature modify the state of equilibrium?" In the first approach, the answer is yes as a result of a common students' alternative conception; the second approach, valid only for ideal…

I will propose here an alternative method for determining atomic radii of alkali metals based on the Hall measurements of their free electron densities and the knowledge of their crystal structure. (Contains 2 figures.)

We analysed the heating curve of water which is described in textbooks. An experiment combined with some simple heat transfer calculations is discussed. The theoretical behaviour can be altered by changing the conditions under which the experiment is modelled. By identifying and controlling the different parameters involved during the heating…

A simple method, which is based on the principle of moment of forces only, is described for the determination of the density of liquids without measuring the mass and volume. At first, an empty test tube and a solid substance, which are hung on each side of a metre rule, are balanced and the moment arm of the test tube is measured. Keeping the…

Enzymology is one of the fundamental areas of biochemistry and involves the study of the structure, kinetics, and regulation of enzyme activity. Research in this area is often conducted with purified enzymes and extrapolated to "in vivo" conditions. The specificity constant, k[subscript S], is the ratio between k[subscript cat] (the catalytic…

The classic experiment presented in this problem-solving test was designed to identify the template molecules of translation by analyzing the synthesis of phage proteins in "Escherichia coli" cells infected with bacteriophage T4. The work described in this test led to one of the most seminal discoveries of early molecular biology: it dealt a…

Given the emphasis on community engagement in higher education, academic departments need to become more involved in the community. This paper discusses a number of outreach activities undertaken by the chemistry department at Rhodes University, South Africa. The activities range from service learning to community engagement with teachers and…

A wind energy focused curriculum for grades 4-8 was designed and implemented to promote the understanding of wind energy concepts with American Indian students. 57 students who participated in the 2009 summer program of the "Reach for the Sky" (RFTS) Science, Technology, Engineering, and Mathematics (STEM) received the curriculum. The…

The apartheid policies in South Africa had a marked influence on the accessibility and quality of school science experienced by the different race groups. African learners in particular were seriously disadvantaged in this regard. The issues of equity and redress were foremost in transformation of the education system, and the accompanying…

The objective of this paper is to provide some practical insight into the process of implementing large-scale randomized controlled trials (RCT) in educational settings and to provide general recommendations for researchers conducting education-based RCTs in the future. The authors draw their recommendations from their recent experiences…

The learning outcome of a physics laboratory course for medical students was examined in an interdisciplinary field study and discussed for the electrical physiology ("Propagation of Excitation and Nerve Cells"). At the Ludwig-Maximilians-University of Munich (LMU) at a time about 300 medicine students were assessed in two successive…

Research-based learning in a teaching environment is an effective way to help bring the excitement and experience of independent bench research to a large number of students. The program described here is the second of a two-semester biochemistry laboratory series. Here, students are empowered to design, execute and analyze their own experiments…

The Independent Laboratory Access for the Blind (ILAB) project has developed a suite of speech accessible tools for students who are blind or low vision to use in secondary and postsecondary science laboratory classes. The following are illustrations of experiments designed to be used by educators to introduce them to the ILAB tools, and to…