This study uses graphs of conductivity measured by a microcomputer-based laboratory (MBL) to promote students' macro, micro, and symbolic representations when learning about net ionic reactions (NIR). A total of 54 students, aged 14-15 years old participated in this research, and were randomly divided into an experimental group (N = 27) and a…

A robust knowledge of physics entails deeply understanding electricity concepts such as conductivity and resistance. Understanding how circuits work is also critical for ensuring the safe use of electrical technology such as car batteries and downed powerlines. Curricular materials covering these content ideas are readily available for teachers.…

Here, we present an interdisciplinary educational project intended for high school chemistry that is focused on the establishment of a mathematical model to describe the relationship between conductivity and concentration, while linking chemistry to mathematics with the help of computer software. The project was designed to help high school…

The precise measurement of conductivity of a semiconductor film such as polypyrrole (Ppy) should be carried out by the four-point probe method; however, this is difficult for classroom application. This article describes the development of a new, convenient, handmade conductivity device from inexpensive materials that can measure the conductivity…

Electrocardiography (ECG) is one of the most widely used methods in clinical diagnosis. Here we describe an experimental approach that offers hands-on learning of its basic principles. An experimental model that consists of a rubber foil with a low electrical conductivity and a DC power unit is used to simulate the body and the electric dipole of…

Two bodies initially at different temperatures gathered into an isolated container exchange heat and reach an equilibrium state with a common final temperature. During the process, the system is out of equilibrium and its intermediate temperature is not well defined. By conceiving a quasi-static process with infinitesimal steps from the initial to…

This empirical study investigates the main features of curricula and contexts that favor or hinder the process of transfer of a teaching-learning sequence (TLS) from the designers' original situation to a host one. The specific research questions addressed were (RQ1) what were the changes made during the process of transfer in the new context?…

The paper describes a set of physics demonstration experiments where thermal sensitive foils are used for the detection of the two dimensional distribution of temperature. The method is used for the demonstration of thermal conductivity, temperature change in adiabatic processes, distribution of electromagnetic radiation in a microwave oven and…

Periodic conductivity trends are placed in the scope of lithium-ion batteries, where increases in the ionic radii of salt components affect the conductivity of a poly(ethyleneoxide)-based polymer electrolyte. Numerous electrolytes containing varying concentrations and types of metal salts are prepared and evaluated in either one or two laboratory…

The classic technique for sulfate analysis in an undergraduate quantitative analysis lab involves precipitation as the barium salt with barium chloride, collection of the precipitate by gravity filtration using ashless filter paper, and removal of the filter paper by charring over a Bunsen burner. The entire process is time-consuming, hazardous,…

In this activity, freshman college students learn biotechnology techniques while playing the role of a laboratory technician. They perform simulations of three diagnostic tests used to screen newborns for cystic fibrosis. By performing an ELISA, a PCR analysis, and a conductivity test, students learn how biotechnology techniques can be used to…

Providing instant visual feedback, thermal imaging cameras are becoming more and more popular tools not only in industrial applications, but also in physics education. Continuously decreasing prices, modules compatible with smart portable devices, and intuitive operation make thermal measurements available for schools and attractive for students.…

Electronic textiles (e-textiles)--fabrics embedded with electrical or electronic components--offer a new model for teaching this content. E-textiles also engage students in programming and engineering design through nontraditional projects and materials. This article describes a four-week electricity curriculum using three e-textiles projects that…

The collision model is frequently introduced to describe electronic conductivity in solids. Depending on the chosen approach, the introduction of the collision time can lead to erroneous results for the average velocity of the electrons, which enters the expression for the electrical conductivity. In other textbooks, correct results are obtained…

Explains how electrical conductivity (EC) can be used to measure ion concentration in solutions. Describes instrumentation for the measurement, temperature dependence and EC, and the EC of common substances. (PR)