An electric motor converts electrical energy into mechanical work and an electric generator converts mechanical work into electrical energy. The symmetry between the motor and generator naturally leads to questions about creating a perpetual motion machine. The allure of this question has inspired textbook problems, physics education articles, and…

A simple experimental setup using a smartphone and a pair of speakers is presented to perform an accurate experiment on interference of two point sources. The proposed experiment allows simple but interesting measurements to be done to introduce students to interference and diffraction phenomena. As such, the experiment effectively introduces the…

Under most conditions, a liquid mixture does not have long-range structural order and may be considered to be a homogeneous collection of molecules in random motion. However, if a single-phase critical mixture of a partially miscible liquid--liquid system is subjected to a small temperature jump into the two-phase region, then structural coherence…

Water electrolysis is used to teach important and fundamental concepts in chemistry. In practical water electrolysis experiments, it is difficult to achieve the ideal 2:1 ratio of hydrogen to oxygen. This work demonstrates an experimental setup comprising multiple water electrolysis cells connected in series to simultaneously visualize the effects…

As simple and ubiquitous redox-active organic molecules, quinones participate in diverse electron transfer processes in chemistry and biological systems for energy transformation and signal transduction. We introduce here a practical exercise to study the redox potentials of benzoquinone and its two derivatives by combining the electrochemistry…

The thermal equilibration of himic anhydride [IUPAC (2-"endo,"3-"endo")-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride] to (2-"exo,"3-"exo")-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride and subsequent recrystallization of the "exo"-product can be performed as a standard…

Already when they enter primary school, children have rich everyday experience with factors influencing the rate of liquids' evaporation. Tea spilled into a large puddle on the table evaporates more rapidly than the same amount remaining in the cup, laundry hanging on a clothesline dries faster on a hot and windy day in comparison with a cold and…

A hula hoop rotating around a person's waist is an example of circular motion where the centripetal force on the hoop is directed towards the centre of the circle rather than the centre of the hoop. The friction force on the hoop is relatively small by comparison since the hoop rolls around the waist. A slight complication is that the hoop rotates…

Generated information is better recognized and recalled than information that is read. This so-called "generation effect" has been replicated several times for different types of material, including texts. Perhaps the most influential demonstration was by McDaniel et al. (1986, "Journal of Memory and Language," 25, 645-656;…

The Hofmeister series is a recurring trend that ranks ions' abilities to influence various aqueous processes in solution. Herein, a set of project-based experiments was developed for students in an upper-level physical chemistry laboratory to investigate the specific ion effects on the thermodynamics of caffeine partitioning between aqueous and…

The ability to visualize chemical processes can be an asset in a teaching laboratory. Despite the advances in laboratory technology, apparatuses used in the teaching of simple thermodynamics concepts, such as exothermic/endothermic reactions, historically remain unchanged and can benefit from a fresh perspective. The recent incorporation of…

We report the findings of an empirical study that investigated whether the source of data--firsthand or secondhand data gained from lab work experiments--has an influence on students' learning outcomes. Results indicate that students' choice of a correct or incorrect hypothesis for a pendulum lab experiment on the influence of the mass of the bob…

This study intended to confirm differences in peer relations between inquisitive and noninquisitive experiment class through social network analysis. In this study, inquiry science experiment classes for 30 students and noninquiry science experiment classes for different 30 students in the chapter named ‚Animals and Energy? of the second year of…

Purpose: Steiner schools represent a natural experiment in the provision of schooling. With a history dating back more than 100 years, leadership, leaders and the principal do not sit easily with Steiner educators. The contemporary regulatory environment requires a "principal" or legal authority at the school-building level, creating a…

Enhancing the problem-solving skills of learners belonging to socio-economically disadvantaged groups is a great concern in general and particularly in the Indian context. Problem-solving skills are the most important skills of the 21st century for all learners to acquire necessary competencies. The main purpose of this work is to investigate the…