An educational activity is described in which the structure and physical properties of disposable plastic cups were directly related to the method of processing. The mechanical properties of specimens cut from the walls of poly(ethylene terephthalate) (PETE) cups, oriented parallel and perpendicular to the thermoforming direction, were measured in…

An introductory level green chemistry experiment is described that places a new twist on soap-making in lab. In this experiment, oil is extracted from an avocado, after which the oil is saponified to produce bars of green craft soap. Commonly used extraction solvents, such as petroleum ether, methylene chloride, and hexane, are replaced with safer…

A laboratory exercise for the education of students about thermal runaway reactions based on the reaction between aluminum and hydrochloric acid as a model reaction is proposed. In the introductory part of the exercise, the induction period and subsequent thermal runaway behavior are evaluated via a simple observation of hydrogen gas evolution and…

A method to determine the temperature dependence of copper wire resistance is described in this paper.

An educational card game, "Chemical Alias," has been developed as an alternative method of reviewing students' knowledge of nomenclature. In contrast to conventional tests, this highly competitive activity is a fun and effective way to examine and reinforce nomenclature. The students play in pairs, using Clark's famous spiral arrangement…

The concept of oxidation state (or oxidation number) and related issues have always been difficult for students. In addition, there are misunderstandings and obscurities, which can cause improper balancing of the chemical equations (mostly in organic reactions). In particular, these problems are related to determination of the oxidation state of…

We propose the use of smartphone-based slow-motion video analysis techniques as a valuable tool for investigating physics concepts ruling mechanical wave propagation. The simple experimental activities presented here, suitable for both high school and undergraduate students, allows one to measure, in a simple yet rigorous way, the speed of pulses…

The Trolley Problem as defined in this paper is a series, or continuation, of increasingly difficult ethical riddles successfully implemented in a classroom environment to spur complex, critical thinking and dialogue. The activity is designed upon the scenario of a runaway train with different and challenging choices, segueing neatly into group…

Mole to gram conversions, density, and percent composition are fundamental concepts in first year chemistry at the high school or undergraduate level; however, students often find it difficult to engage with these concepts. We present a simple laboratory experiment utilizing portable nuclear magnetic resonance spectroscopy (NMR) to determine the…

A syringe-based, electronic fluid dispenser is described. The device mechanically connects a syringe plunger to a linear slide potentiometer. As the syringe plunger moves, the electrical resistance between terminals of the potentiometer varies. Application and subsequent measurement of a DC voltage between the potentiometer pins is used to track…

A demonstration of the degradation of food coloring dyes by oxidation via the Fenton reaction can be substituted with a simpler demonstration using the oxidant oxone with iron(II) ions as an activator. The addition of small amounts of solid oxone and iron(II) sulfate to solutions containing mixtures of food coloring results in successive…

This study examines the validity of the current SAT® as a predictor of first-year academic performance and retention to the second year by student and institutional subgroups across more than 223,000 students from 171 four-year institutions. Results show that institutions can feel confident using SAT scores and HSGPA for admission, scholarship,…

In this paper, we present a low-cost method to study the Gay-Lussac's law. We use a heating wire wrapped around the test tube to heat the air inside and make use of a solid state pressure sensor which requires a previous calibration to measure the pressure in the test tube.

A simple and ecofriendly procedure was developed in order to prepare extracts from red and green leaves. This procedure enables the separation of yellow, green, and red band pigments and optimizes the previously reported baking soda "supermarket column". The same extract also led to a novel and colorful potato starch column, which can…

There is a popular myth that Galileo dropped two objects of the same shape but different mass, noted their equal fall time, and concluded that gravitational motion is independent of the mass of the object. This paper demonstrates that this experiment--if actually performed--most likely would have yielded a different result and thus with modern…