We have developed a simple and direct method to fabricate paper-based microfluidic devices that can be used for a wide range of colorimetric assay applications. With these devices, assays can be performed within minutes to allow for quantitative colorimetric analysis by use of a widely accessible iPhone camera and an RGB color reader application…

For most chemistry curricula, laboratory-based activities in quantitative and instrumental analysis continue to be an important aspect of student development/training, one that can be more effective if conceptual understanding is delivered through an inquiry-based process relating the material to relevant issues of public interest and student…

Current atom concept teachings haven't reached required levels from the points of both teaching methods and learning attainments. With this purpose in this research atom concept is conveyed to the classroom milieu through observations and experiments related to the atom concept during historical development process starting with the masterpiece…

An upper-division organic chemistry laboratory experiment exploring fluorescent sensing over two laboratory periods and part of a third is described. Two functionally distinct pH-responsive sensors are prepared through a dehydrative three-component coupling reaction. During the abbreviated (<1 h) first laboratory period, students set up…

This paper describes an inexpensive experiment to determine the carbonyl stretching frequency of an organic keto compound in its ground state and first electronic excited state. The experiment is simple to execute, clarifies some of the fundamental concepts of spectroscopy, and is appropriate for a basic spectroscopy laboratory course. The…

We developed a simple, cost-effective, and eco-friendly method to synthesize gold nanoclusters (AuNCs) with red fluorescence. The experiment was performed using HAuCl[subscript 4], egg white, Na[subscript 2]CO[subscript 3] (known as soda ash or washing soda), and a microwave oven. In our experiment, fluorescent AuNCs were prepared within a…

Teaching children about circuits and the way electricity works is a "tricky business" because it is invisible. Just imagine all eyes are on the teacher as he or she produces for the class what looks like a ping-pong ball and then, with a wave of their hand, the incredible happens! This wonderful white sphere begins to glow red and a…

To help students make the connection between the concepts of heat conduction and convection to real-world phenomenon, we developed a combined experimental and computational module that can be incorporated into lecture or lab courses. The experimental system we present requires materials and apparatus that are readily accessible, and the procedure…

The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction velocities…

Numerous nanoparticle (NP) fabrication methodologies employ "bottom-up" syntheses, which may result in heterogeneous mixtures of NPs or may require toxic capping agents to reduce NP polydispersity. Tangential flow filtration (TFF) is an alternative "green" technique for the purification, concentration, and size-selection of…

An experiment is described that determines the activation energy (E[subscript a]) of the iodide-catalyzed decomposition reaction of hydrogen peroxide in a much more efficient manner than previously reported in the literature. Hydrogen peroxide, spontaneously or with a catalyst, decomposes to oxygen and water. Because the decomposition reaction is…

This paper describes a physics laboratory exercise for determining the coefficient of static friction between two surfaces. The circular motion of a coin placed on the surface of a rotating turntable has been studied. For this purpose, the motion is recorded with a high-speed digital video camera recording at 240 frames s[superscript-1], and the…

Comparing two objects falling together is a small-scale version of Galileo's classical experiment, demonstrating the equivalence between gravitational and inertial mass. We present here investigations by a group of ten-year-olds, who used iPads to record the drops. The movie recordings were essential in the follow-up discussions, enabling the…

Helping students develop an understanding of how to interpret experimental data trends is an important part of the introductory physics laboratory. Unfortunately, many of my colleagues have lamented that too many of their students do this poorly. This is a common refrain, and past research has already revealed student difficulties with…

Doing science as explorers, students observe, wonder and question the unknown, stretching their experience. To engage students as explorers depends on their safety in expressing uncertainty and taking risks. I create these conditions in my university seminar by employing critical exploration in the classroom, a pedagogy developed by Eleanor…