The coefficient of restitution (COR) for a collision is usually a number between 0 and 1 depending on whether the collision is completely inelastic, or perfectly elastic or something in between. That is the usual situation for colliding spheres or a ball dropped on a horizontal surface. A different situation arises when a bat collides with a ball.…

This study focuses on the experimental demonstration of the definition of kelvin using a triple point of water (TPW) cell and estimates the measurement uncertainty. The first part of this article is to construct the measurement setup and perform the measurements. The second stage is related with the calculation of uncertainty according to guides…

In the present study, atmospheric pressure, an abstract concept that learners generally have difficulty understanding and explaining, was presented to pre-service elementary teachers (PSTs) with the method of argumentation. The argument levels of the PSTs were examined using the Predict-Observe-Explain (POE) experiments in teaching the subject of…

Quantum dots are colloidal semiconductor nanocrystals that display size-dependent electronic and optical properties. These materials are a visual demonstration of a quantum-mechanical effect. Here we present a laboratory exercise for undergraduate/Bachelor students as an introduction to colloidal nanocrystals and quantum dots. The students…

In this paper, we present a concise and technique-heavy route to the synthesis of dimedone for a second-year organic chemistry curriculum. Our preparation of dimedone guides students through a Michael addition followed by a Dieckmann cyclization, basic ester hydrolysis, and thermal decarboxylation, while allowing time for mechanistic discussion…

Calorimetry is a central concept in the first semester general chemistry curriculum, and constant pressure (coffee-cup) calorimetry is a common experiment in the laboratory. However, constant volume (bomb) calorimetry is traditionally reserved for the physical chemistry laboratory. This article describes the advantages of incorporating bomb…

Providing hands-on practical education without access to laboratories during the COVID-19 pandemic has required creativity and innovation. In this paper, co-authored by academic staff and students, we describe an at-home mobile phone-based 'spectrophotometer' experiment used in an introductory undergraduate biology course. Using colour picker…

Purpose: The aim of this research is to determine the impact of hands-on science activities on preschool children's motivation for science. Design/Approach/Methods: The study group of the research, in which the quasi-experimental design with pretest-posttest control group was used, consists of 25 children aged 60-72 months who are continuing their…

Red onion, "Allium cepa," juice can dye a cloth sample green upon the addition of alum, aluminum potassium sulfate, and this sample can turn red when subjected to an acidic solution. When the red-colored sample is washed with a neutral or alkaline aqueous solution, its color turns green again. These experiments illustrate color changes…

By hosting a college students' laboratory skills contest, we provide an interesting activity for students to cultivate good laboratory practices and thereby improve their laboratory skills. The substance of this contest is the detection of the hardness of water, which involves numerous laboratory skills such as solution preparation, weight by…

With the increase of waste paper, environmental pollution and atmospheric impact have become global problems. The cellulose contained in waste paper has the advantages of being renewable and biodegradable and can be applied to many fields to achieve sustainable development. At present, thermal management materials, as a new type of material, have…

A standard physics experiment for students is to measure the terminal velocity of an object in air or in glycerine. A more difficult challenge is to measure the terminal velocity in water since the depth of the water needs to be large or the object needs to be dropped in the water at a speed close to its terminal velocity. Results obtained by…

One step of the published mechanism of the hydrogen peroxide iodine-clock reaction is called into question by the result of an experimental attempt (predicated on that mechanism) to integrate that reaction into the elephant's toothpaste demonstration to reveal and control its iodine side product. Under conditions that were a hybrid of those…

Carbonated beverages have long provided chemical educators and other teachers of science with an easy-to-obtain system that connects to several physicochemical concepts. For example, many educators have devised experiments to determine the pressure of CO[subscript 2] contained in commercial carbonated beverages, but the role of temperature in such…

In this paper we consider the well-known experiment with the 'heavy' newspaper that breaks a stick that it is laid on. Using several appropriate control experiments we show that the currently invoked explanation using atmospheric pressure cannot be correct. We perform a theoretical analysis and propose a new explanation based on the rotational…