Huddle, Penelope Ann, White, Margaret Dawn, and Rogers, Fiona
Journal of Chemical Education, v77 n1 p104-10 Jan 2000.
Chemistry, Demonstrations (Science), Electric Circuits, Electricity, Electrochemistry, High Schools, Higher Education, Instructional Materials, Misconceptions, Science Activities, Science Education, Science Equipment, Scientific Concepts, and Teaching Methods
Describes a concrete teaching model designed to eliminate students' misconceptions about current flow in electrochemistry. The model uses a semi-permeable membrane rather than a salt bridge to complete the circuit and demonstrate the maintenance of cell neutrality. Concludes that use of the model led to improvement in students' understanding at the high school and university levels. (Contains 27 references.) (WRM)
Journal of Chemical Education, v75 n2 p181-82 Feb 1998.
Acids, Alternative Energy Sources, Calculators, Chemistry, Demonstrations (Science), Electricity, Electrochemistry, Elementary Secondary Education, Higher Education, Introductory Courses, Relevance (Education), Science Activities, Science Education, Scientific Concepts, and Student Motivation
Describes a demonstration of the principles of a voltaic cell using lemon cells to power a calculator and other items. A lemon fortified with a penny and a galvanized nail produces a potential of one volt. (PVD)
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 experiments that use the device. (JRH)
Journal of Chemical Education, v73 n5 p457-59 May 1996.
Chemistry, Demonstrations (Science), Electricity, Electrochemistry, Higher Education, and Secondary Education
Extends the work of Weimer and Battino in electrical conductivity demonstrations creating "glowing" vegetables (see article this issue) to other vegetables and the spectra generated by other elements other than the sodium in pickle brines. Describes a study on the effect of concentration and voltage on glow intensity. (MKR)
Presents an experiment designed to give students some experience with photochemistry, electrochemistry, and basic theories about semiconductors. Uses a liquid-junction solar cell and illustrates some fundamental physical and chemical principles related to light and electricity interconversion as well as the properties of semiconductors. (JRH)