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…

The ideal gas law, "PV = nRT," is one of the simplest physical laws in nature that is introduced to students as early as in high school and first year in college. In this equation, "P" stands for pressure, "V" is the volume, "n" is the amount expressed in mole, "T" is the temperature in Kelvin…

Various experiments on vibrating gas columns and on frequency measurements with glasses and pipes have been presented in recent years in the "iPhysicsLabs" column. The determination of the sound velocity in different gases by measuring the sound running time has also already been proposed in an earlier paper. This article now adds…

In this article we consider a well-known simple, very accessible demonstration of surface tension with a small boat propelled by substances that change the surface tension of water. A simple quantitative evaluation is provided that matches well with experimental data. A modification to the experiment is proposed allowing it to continue for a long…

Thermal conductivity is generally the tool of choice for quantification of fixed gases, particularly lighter-than-air gases. Unfortunately, gas chromatography-thermal conductivity detectors (GC-TCDs) are difficult to introduce in first- and second-year chemistry courses where the cost and number of instruments, as well as the space required, is…

Biodiesel is an important biomass, largely employed in the transport sector and produced from vegetable oils. Additionally, waste cooking oils may be reused to produce biodiesel fuel, minimizing environmental pollution. A laboratory experiment that affords a widespread way to discuss degradation concepts and tools for used vegetable oil…

With the benefits of low cost, energy efficiency, and environmental protection, photocatalytic hydrogen production is considered to be the most promising technology for the development of a clean and sustainable society. However, the utilization of photocatalytically generated hydrogen is not very common yet. Therefore, tertiary education urgently…

In the activity described in this communication, the authors present a simple experiment that can be implemented with moderate operational costs and that allows students to acquire the manipulative skills necessary for chromatographic analysis of a familiar fuel that still plays a fundamental role in providing energy for transport of passengers…

A modular experiment for upper-level undergraduate students is presented, featuring the product cycle and process evaluating the quality and quantity of biodiesel obtained from a microalgae feedstock grown under carbon-supplemented and nutrient-deprived conditions. Batch reactors are used to cultivate and harvest microalgae, which undergo…

A safe, convenient, and environmentally benign laboratory experiment for the synthesis of biodiesel from six kinds of vegetable oils has been developed for the introductory organic chemistry laboratory. The experiment uses ultrasonic irradiation in the presence of a base catalyst at room temperature and atmospheric pressure. Because of safer and…

This laboratory experiment leverages the pedagogical value and multidisciplinary nature of biodiesel production from vegetable oil to introduce students to continuous-flow chemistry, a modern and rapidly growing approach to chemical synthesis. An interdisciplinary approach exposes students to the practical and conceptual aspects of modern…

The "safety lamp" invented by Humphrey Davy in 1815 utilised the cooling effect of metal gauze to prevent the flame of a candle or oil lamp (essential for illumination in mines) from passing through such a screen. It is therefore rendered unable to ignite any potentially explosive mixture of air and methane in the atmosphere surrounding…

We describe an activity that is suitable for high school students and makes use of plastic bottles. This activity allows students to familiarize themselves with gas chemistry by introducing technologies that were applied in old submarine systems. Plastic bottles, which are representative of submarines, are used as reaction vessels. Three simple…

Gas chromatography-mass spectrometry (GC-MS) and GC-tandem MS (GC-MS/MS) are useful in many separation and characterization procedures. GC-MS is now a common tool in industry and research, and increasingly, GC-MS/MS is applied to the measurement of trace components in complex mixtures. This report describes an upper-level undergraduate experiment…

A simple capacitive cell for dielectric constant measurement in liquids is presented. As an illustrative application, the cell is used for measuring the degradation of overheated edible oil through the evaluation of their dielectric constant.